Designing With Surfaces 2001

PTC Global Services

DDeessiiggnniinngg WWiitthh SSuurrffaacceessRelease 2001

T868-320-01

Training AgendaDesigning With SurfacesDay 1

Introduction to Surfacing

Initial Surfaces

Geometry for Surfaces: Points and Curves

Manipulating Surfaces

Modifying Solid Surfaces Using Quilts

Day 2

Creating Solids Using Quilts

Boundary Surfaces

Variable Section Sweeps

Swept Blends

Day 3

Surface Information and Analysis

Surfaces Continuities

Additional Advance Surfacing Tools

Working with Imported Surfaces

Table of ContentsDesigning With Surfaces

INTRODUCTION TO SURFACING 1-1DESIGNING WITH SURFACES...................................................................................... 1-2

Using Surfacing..................................................................................................................1-2

SURFACE FUNDAMENTALS ........................................................................................ 1-3

Surface Patches...................................................................................................................1-4

Quilts ..................................................................................................................................1-4

Surface Display ..................................................................................................................1-5

SURFACE ATTRIBUTES ................................................................................................ 1-5

Surface Normals .................................................................................................................1-5

Sides of a Surface ...............................................................................................................1-6

Curvature ............................................................................................................................1-7

Surface Continuities ...........................................................................................................1-8

CREATING SURFACES .................................................................................................. 1-8

Surface Creation Techniques..............................................................................................1-9

USING SURFACES ........................................................................................................ 1-10

Creating Solid Features from Surfaces .............................................................................1-10

Manipulating Solid Surfaces ............................................................................................1-11

Removing Material from a Solid ......................................................................................1-11

ANALYZING SURFACES ............................................................................................. 1-11

MODULE SUMMERY.................................................................................................... 1-13

INITIAL SURFACES 2-1CREATING SURFACES .................................................................................................. 2-2

Creating an Enclosed Volume ............................................................................................2-2

EXTRUDED SURFACES ................................................................................................. 2-3

REVOLVED SURFACES ................................................................................................. 2-4

BLENDED SURFACES .................................................................................................... 2-4

Attributes ............................................................................................................................2-4

Orienting the Sections ........................................................................................................2-4

Additional Blended Surface Properties ..............................................................................2-6

Swept Surfaces ...................................................................................................................2-8

Attributes of Swept Surfaces ..............................................................................................2-9

FLAT SURFACES ...........................................................................................................2-10

USING SURFACES TO CREATE ADDITIONAL SURFACES ...................................2-11

Copying Surfaces ............................................................................................................. 2-11

Offset Surfaces................................................................................................................. 2-12

LABORATORY PRACTICAL........................................................................................2-13

EXERCISE 1: Creating the Handle and Top of a Plastic Bottle ...................................... 2-13

MODULE SUMMARY....................................................................................................2-28

GEOMETRY FOR SURFACES: POINTS & CURVES 3-1DATUM POINTS...............................................................................................................3-2

Creating Datum Points ....................................................................................................... 3-2

DATUM CURVES.............................................................................................................3-4

Creating Datum Curves...................................................................................................... 3-4

Sketching Splines and Conics ............................................................................................ 3-5

Defining Curves through the Points ................................................................................... 3-9

Creating Curves from Files .............................................................................................. 3-11

Composite Datum Curves ................................................................................................ 3-12

Projected Curves .............................................................................................................. 3-13

Formed Curves................................................................................................................. 3-14

From Equation ................................................................................................................. 3-14

From Boundary ................................................................................................................ 3-15

Offset from Surface.......................................................................................................... 3-15


EXERCISE 1: Creating Datum Curves............................................................................ 3-17

EXERCISE 2: Creating Curves to Build Surfaces........................................................... 3-25

MODULE SUMMARY....................................................................................................3-35

MANIPULATING SURFACES 4-1Extending Surfaces ............................................................................................................ 4-2

Specifying the Surface Extension Distance ....................................................................... 4-4

Extending Edges ................................................................................................................ 4-5

Trimming Surfaces............................................................................................................. 4-6

Transforming Surfaces....................................................................................................... 4-7

Merging Surfaces ............................................................................................................... 4-8


EXERCISE 1: Manipulating Surfaces ............................................................................. 4-10

MODULE SUMMARY....................................................................................................4-19

MODIFYING SOLID SURFACES USING QUILTS 5-1USING QUILTS TO MANIPULATE SOLIDS ................................................................ 5-2

REPLACING SURFACES ................................................................................................ 5-2

PATCHING........................................................................................................................ 5-3

USING QUILTS TO CUT SOLIDS .................................................................................. 5-4

LABORATORY PRACTICAL ......................................................................................... 5-5

EXERCISE 1: Creating a Stiffener and a Rib for Fuselage................................................5-6

EXERCISE 2: Creating Cuts Using Surfaces...................................................................5-16

MODULE SUMMARY ................................................................................................... 5-21

CREATING SOLIDS USING QUILTS 6-1USING QUILTS TO GENERATE SOLID FEATURES .................................................. 6-2

Creating a Thin Feature ......................................................................................................6-2

Protruding a Solid Feature..................................................................................................6-2

Combining an Intersecting Quilt ........................................................................................6-3

OFFSETTING SURFACES............................................................................................... 6-4

Offset Methods ...................................................................................................................6-4

LABORATORY PRACTICAL ......................................................................................... 6-9

EXERCISE 1: Creating a Solid Part of a Car Hood.........................................................6-10

EXERCISE 2: Using Offset Surfaces for Shelling...........................................................6-15

MODULE SUMMARY ................................................................................................... 6-20

BOUNDARY SURFACES 7-1CREATING SURFACES USING BOUNDARIES........................................................... 7-2

BLENDED SURFACES .................................................................................................... 7-2

Blended Surface with Approximate Curves .......................................................................7-5

CONIC SURFACES .......................................................................................................... 7-7

N-SIDED SURFACES....................................................................................................... 7-8

RIBBON SURFACES........................................................................................................ 7-8

LABORATORY PRACTICAL ....................................................................................... 7-10

EXERCISE 1: Blending Surfaces.....................................................................................7-11

EXERCISE 2: Changing Blend Control Points................................................................7-29

MODULE SUMMARY ................................................................................................... 7-37

VARIABLE SECTION SWEEP 8-1THE VARIABLE SECTION SWEEP............................................................................... 8-2

Defining Trajectories..........................................................................................................8-2

Specifying Section Orientation...........................................................................................8-2

Adding Control: Using Relations in Variable Section Sweeps ..........................................8-5

Restrictions on Variable Section Sweeps........................................................................... 8-7

LABORATORY PRACTICAL..........................................................................................8-8

EXERCISE 1: Using Variable Section Sweeps to Design the Plastic Bottle..................... 8-9

EXERCISE 2: Creating a Wavy Washer ......................................................................... 8-22

MODULE SUMMARY....................................................................................................8-25

SWEPT BLENDS 9-1INTRODUCTION ..............................................................................................................9-2

Defining the Origin Trajectory........................................................................................... 9-2

Creating Sections ............................................................................................................... 9-2

Additional Controls to Modify the Swept Blend Feature................................................... 9-4

Restrictions on Swept Blends............................................................................................. 9-6

LABORATORY PRACTICAL..........................................................................................9-7

EXERCISE 1: Creating a Manifold ................................................................................... 9-8

MODULE SUMMARY....................................................................................................9-17

SURFACE INFORMATION & ANALYSIS 10-1ANALYZING GEOMETRY............................................................................................10-2

Gaussian Curvature .......................................................................................................... 10-3

Section Curvature............................................................................................................. 10-4

Slope ................................................................................................................................ 10-5

Porcupine ......................................................................................................................... 10-5

Normals............................................................................................................................ 10-6

Draft Check...................................................................................................................... 10-6

Reflection Curves............................................................................................................. 10-6

Radius .............................................................................................................................. 10-7

Offset Mesh...................................................................................................................... 10-7

Deviation.......................................................................................................................... 10-8

Highlight Curves .............................................................................................................. 10-8

Information at a Certain Point.......................................................................................... 10-8

Dihedral Angle................................................................................................................. 10-9

LABORATORY PRACTICAL......................................................................................10-10

EXERCISE 1: Analyzing Surfaces ................................................................................ 10-11

MODULE SUMMARY..................................................................................................10-23

SURFACE CONTINUITIES 11-1THE CURVATURE .........................................................................................................11-2

CONTINUITY BETWEEN GEOMETRIC ENTITIES...................................................11-3

USING CURVATURE CONTINUOUS SURFACES.....................................................11-4

Creating Curvature Continuous Surfaces .........................................................................11-4

Analyzing Curvature Continuous Surfaces ......................................................................11-5


EXERCISE 1: Creating Blended Transitions ...................................................................11-7

MODULE SUMMARY ................................................................................................. 11-16

ADDITIONAL ADVANCE SURFACING TOOLS 12-1USING ADDITIONAL SURFACING OPTIONS .......................................................... 12-2

SECTION TO SURFACE................................................................................................ 12-2

TANGENT TO SURFACE.............................................................................................. 12-3

SURFACE TO SURFACE............................................................................................... 12-4

FREE-FORM SURFACE FEATURES ........................................................................... 12-5

Using Freeform.................................................................................................................12-5

Defining Manipulate Options ...........................................................................................12-6

Using Dynamic Diagnostics .............................................................................................12-7


EXERCISE 1: Creating Draft Surfaces of a Boss ............................................................12-9

EXERCISE 2: Free Form Manipulation.........................................................................12-14

MODULE SUMMARY ................................................................................................. 12-20

WORKING WITH IMPORTED SURFACES 13-1WORKING WITH IMPORTED SURFACES................................................................. 13-2

Working Method ..............................................................................................................13-3

WORKING WITH PROBLEM SURFACES .................................................................. 13-3

Identifying Problematic Surfaces .....................................................................................13-4

Repairing Problems during Import ...................................................................................13-5

Repairing the Imported Geometry....................................................................................13-6

Deleting Imported Geometry..........................................................................................13-13

Excluding Surfaces.........................................................................................................13-14

LABORATORY PRACTICAL ..................................................................................... 13-15

EXERCISE 1: Fixing Imported Surface Boundaries......................................................13-15

MODULE SUMMARY ................................................................................................. 13-30

ADDITIONAL EXERCISES A-1LABORATORY PRACTICAL ........................................................................................ A-2

EXERCISE 1: Creating a Gear Sector ..............................................................................A-2

EXERCISE 2: Creating a Helical Cut .............................................................................A-14

EXERCISE 3: Creating Difficult Rounds .......................................................................A-20

USING PTC HELP B-1PTC HELP OVERVIEW...................................................................................................B-2

PTC Help Features ............................................................................................................ B-2

USING THE Pro/ENGINEER HELP SYSTEM ...............................................................B-2

Launching Help: Four Methods ........................................................................................ B-2

PTC HELP MODULE LIST..............................................................................................B-7

PTC GLOBAL SERVICES: TECHNICAL SUPPORT C-1FINDING THE TECHNICAL SUPPORT WEB PAGE...................................................C-2

OPENING TECHNICAL SUPPORT CALLS ..................................................................C-2

Opening Technical Support Calls via E-mail.....................................................................C-2

Opening Technical Support Calls via Telephone...............................................................C-3

Opening Technical Support Calls via the Web ..................................................................C-3

Sending Data Files to PTC Technical Support...................................................................C-3

Routing Your Technical Support Calls ..............................................................................C-4

Assigning Technical Support Call Priorities......................................................................C-5

Software Performance Report Priorities ............................................................................C-5

REGISTERING FOR ON-LINE SUPPORT.....................................................................C-5

ONLINE SERVICES.........................................................................................................C-6

FINDING SOLUTIONS IN THE KNOWLEDGE BASE ................................................C-6

Terminology used by Technical Support ...........................................................................C-7

GETTING UP-TO-DATE INFORMATION ....................................................................C-8

CONTACT INFORMATION............................................................................................C-9

PTC Technical Support Worldwide Electronic Services. ..................................................C-9

Telephone.........................................................................................................................C-10

ELECTRONIC SERVICES.............................................................................................C-14

INDEX

Page 1-1

Module

Introduction to SurfacingIn this module you learn the fundamentals of Pro/ENGINEER

surfacing, including the surfacing concepts for defining complex

shapes and fixing imported surfaces.

Objectives

After completing this module, you will be able to:

• Define the advantages of the Pro/ENGINEER surfacing features.

• Conceptualize complex designs.

Page 1-2 Des igning w i th Surfaces

NOTES

DESIGNING WITH SURFACESYou can use surfaces to build intelligence and provide flexibility in adesign. Surfaces are used to generate the entire contour of a design. Theycan be manipulated later in the design process to generate the solidcomponents. Surfaces can be used to define a volume to contain a design.The designer/engineer can use this definition to conceptualize acomponent or a subsystem, or to create complex cuts.

Using SurfacingYou can use surfaces to build intelligence into a design without creatingsolid geometry, for example, a map, skeleton, or envelope. When buildingintelligence into a complex model, multiple surfaces can be defined andthen merged together to generate a final solid feature. This enables you togenerate a significant amount of information without the creation ofseveral solid features. You can develop a concise design using surfacingtechniques.

The more typical generation of geometry is through curves, surfaces, andquilts, for example, complex models such as turbine blades.

You use surfaces to define complex shapes in a Pro/ENGINEER model. Inaddition, you use surfacing:

• If the geometry is defined through edges, surface definitions, orsectional information only.

• If the mathematical definitions, such as tangency, are important.

• If there are no obvious methods using traditional solid features tocreate the geometry.

In t roduct ion to Surfac ing Page 1-3

NOTES

SURFACE FUNDAMENTALSSurfaces are infinitely thin, non-solid features used to aid in the design ofhighly complex and irregular shapes.

Figure 1: The Non-Solid Surface Feature

In Pro/ENGINEER, the term surface can be correctly applied whilereferencing any of the following:

• Quilts – Consists of one or a patchwork of connected surface features.

• Solid Surface – The face of a solid feature, as shown in the followingfigure.

• Datum Planes – Infinite planar surfaces that can be used asreferences.

Solid Surface

Datum planes areinfinite flat

surfaces

Figure 2


NOTES

Surface PatchesIf you create boundary surface from several segments, the surface iscreated with multiple patches. The system determines the relative positionof a vertex, then connects it with a vertex on the opposite boundary at thesame relative position.

Boundary madeof multiple curvesegments

Surface patches

Figure 3: Model with Surface Patches

QuiltsA quilt can consist of a single surface or a collection of surfaces. A quiltrepresents a patchwork of connected non-solid surfaces. A multi-surfacequilt contains information describing all the geometry: and how thesurfaces are joined or intersected. To create a quilt made from manysurfaces, you can merge multiple surfaces that share at least one commonboundary.

Multiple connectedsurfaces

Figure 4: A Quilt


NOTES

Surface DisplayWhile working with surfaces, it is important to understand the displaycharacteristics. The one-sided outer edges of a surface feature aredisplayed in yellow. The two-sided inner edges are displayed in magenta.

Pro/ENGINEER displays the surfaces in the Model Tree with the name ofthe surface and a unique ID number. It also displays icons to denotedifferent types of surfaces.

Figure 5: Displaying Surfaces in Model Tree

SURFACE ATTRIBUTES

Surface NormalsSurfaces/quilts vectors are normal to the surface at a given point on thesurface. The surface normals are displayed in U and V directions. You cancontrol the visual display of normals using the controls provided in theSURFACE ANALYSIS dialog box.


NOTES

Figure 6: Surface Normal Vectors

Sides of a SurfaceEvery surface or quilt has two sides, often referred to as the outside andthe inside of a surface. The surface normals point outward from theoutside of a surface. The direction of a surface is an important attribute.For example, the direction influences the assigning of colors anddetermines which side to machine.

A collection of surfaces can have surfaces with normals in differentdirections. This is undesirable for many a reasons. When you mergesurfaces to create a quilt, Pro/ENGINEER changes the direction of thesurface that has different direction than the parent surface/quilt.

Merging the surfaces changesthe surface direction

Figure 7: Surface Normals


NOTES

CurvatureCurvature measures the local bending of a surface. Curvature can becalculated as the reciprocal of the radius (1/radius) at any surface point, asshown in the following figure.

In general, it signifies how much a curve or surface bends at a particularlocation on the curve or surface, for example:

• If a circle has constant curvature.

• If a straight line has zero curvature.

Figure 8: The Concept of Curvature

Figure 9: Surface Curvature Displayed in U and V Direction


NOTES

Surface ContinuitiesTo join the surfaces smoothly, you need to define the continuity betweenadjacent surfaces. There are two types of continuity that you can define.

• Tangent Continuity – Joins two surfaces that have the same tangentat every point along the boundary.

• Curvature Continuity – Joins two surfaces that have the samecurvature from each surface at each point along the boundary.

Figure 10: Tangent and Curvature Continuous Surfaces

CREATING SURFACESSurface creation in Pro/ENGINNER requires a different approach than thesolids creation. You need to develop reference entities, such as points in acurve, in order to create surfaces. It is recommended that you plan themodel before you start to create the surface models. Your design intentdetermines the tool that you use to create a particular surface. To createsurfaces, you use a number of tools that can be classified in following twocategories:

• Simple or Basic – Surface creation methods that are similar to thesolid creation tools. Some of the basic surface creation tools areExtrusion, Sweep and Blend.

• Advanced – Surfacing tools that allow you to create complex shapesand to control the surface design through complex parameters.


NOTES

Surface Creation TechniquesDatum points and curves are the underlying structures to build thesurfaces. For example, they are required to define boundaries or to definetrajectories.

Pro/ENGINEER provides several methods for creation of models fromsurface.

Curve Network

A set of datum curves, or curve network, can be used as the surfaceframework. The curve network can be constructed to represent the surfaceboundaries on the final model. This method is often used to create theirregular surfaces.

Figure 11: Using a Curve Network to Create Surface

Overbuilt Surfaces

Overbuilt or overlapping surfaces can be used to create surface models.These surfaces can be merged together using various methods todetermine the final shape. This method is used mainly for surfaces withsimple geometric shapes.


NOTES

Figure 12: Overbuilt Technique

You can combine both the approaches while defining the surface models.You can use overbuilt surfaces to initialize the model, and then add acurve network to finish the surface models.

USING SURFACESYou can use surfaces to:

• Create solids.

• Manipulate solid surfaces.

• Create cuts.

• Shell a solid model.

Creating Solid Features from SurfacesYou can create a solid feature from a surface using the Protrusion, UseQuilt option.

• Thin Feature – Provides thickness to an open quilt.

• Solid Feature – Creates a solid out of a closed quilt.


NOTES

Figure 13: A Thin Solid Feature

Manipulating Solid SurfacesYou can use quilts to change the shape of a solid surface using thefollowing Tweak options:

• Replace

• Patch

• Free Form

Removing Material from a SolidYou can use quilts to change the shape of solids, for example:

• Cuts – Uses quilts to remove material.

• Shell – Uses quilts to shell a solid model that has complex surfacesand standard shell command is not able to generate the desired results.

ANALYZING SURFACESPro/ENGINEER offers a number of tools to analyze various aspects ofsurfaces. In order to achieve smooth and complex surfaces, you need toanalyze the surfaces using various tools. You can evaluate surfaces to:

• Find out the continuities (smoothness) of the surfaces.

• Determine the surface quality of imported surfaces.

• Determine the aesthetic attributes of a design.


NOTES

Figure 14: Checking Continuity of a Surface Using a Gaussian Tool

Figure 15: Checking the Drafts


NOTES

MODULE SUMMERYIn this module, you have learned that:

• You can use surfaces to define complex shapes.

• In Pro/ENGINEER, the term surface can be referred to a quilt, solidsurface and a datum plane.

• Working with surface modeling requires a different approach thansolids modeling.

• In order to achieve smooth and quality surfaces, you need to analyzethe surfaces.

Page 2-1

Module

Initial SurfacesIn this module you learn to create basic surface features.

Objectives


• Define and create initial surfaces.

• Define the attributes that are unique to the surfaces.


NOTES

CREATING SURFACESSurface features extend the functionality of Pro/ENGINEER. Thoughmost of the initial surfaces are created using the tools that are similar tosolid protrusions, there are subtle differences, such as specifying tangentboundary conditions.

You can use following surfacing methods to create simple surfacefeatures:

• Extrude

• Revolve

• Sweep

• Blend

• Flat

• Offset

• Copy

• Fillet

You can create complex surfaces using following advance surfacingmethods:

• Variable Section Sweep

• Swept Blend

• Helical Sweeps

• Boundaries

• Section To Surfaces

• Surfaces to Surfaces

• From File

• Tangent To Surfaces

• Free Form

Creating an Enclosed VolumeIf a cross-section is closed looped when you are creating extruded,revolved, swept, or blended surfaces, you can use the Capped Endsoption to automatically create flat surfaces that close off the ends of thefeature. The system automatically merges two flat surfaces with the othersurfaces to form a closed volume, as shown in the following figure.

Figure 1: Open and Capped Ends

In i t i a l Surfaces Page 2-3

NOTES

EXTRUDED SURFACESYou can create a surface by extruding a sketched section to a specifieddepth in the direction normal to the sketching plane.

Figure 2: Extruded surface with an Open Section

Extruding a surface is similar to extruding a solid thin feature using theSolid, Protrusion, Thin command. You can sketch an open or closedsection to extrude.

Defining Depth

You can define the depth of an extruded surface using the followingoptions:

• Blind

• Up to Point or Vertex

• Up to Curve

• Up to Surface


NOTES

REVOLVED SURFACESYou can create a surface feature by rotating a sketched section around thefirst sketched centerline.

Defining Angle of Rotation

You can specify the angle of rotation using the following options:

• Variable

• Standard Angles

• Up to Point or Vertex

• Up to Plane

BLENDED SURFACESYou can create a blended surface feature by connecting a series ofsketched sections. You need at least two sections to create a blendedsurface. Also, you need to specify the distance between the sections.

AttributesWhile creating a blended surface you can define the transition between thesections using following options:

• Smooth – Creates a smooth blend by connecting vertices of differentsections with smooth curves. Edges of the sections are connected withspline surfaces.

• Straight – Creates a straight blend by connecting vertices of thedifferent sections with straight lines. Edges of the sections areconnected with ruled surfaces.

Orienting the SectionsYou can choose one of the following options to orient the sections.

• Parallel

• Rotational

• General


NOTES

Parallel Blends

You create a parallel blend by sketching sections that remain parallel tothe sketching plane. You can define the distance between the planes.

Figure 3: Straight & Smooth Blend

Rotational Blends

Sections can be rotated about the Y-axis of a sketcher coordinate systemup to a maximum of 120 degrees. You need to define a coordinate systemin order to specify the rotation.

Figure 4: Rotational Blend

General Blends

Sections can be rotated about and translated along the X, Y, and Z-axes.You need to specify a coordinate system in order to align the sections.This enables parametric control of a twisted blend.


NOTES

Figure 5: General Blend

Additional Blended Surface PropertiesStarting Point of a Section

To create blended surfaces, the system connects the start points of thesections and continues to connect the vertices of the sections in aclockwise manner. You line up the start points in order to createparametrically controllable surfaces, as shown in the following figure.

Figure 6: Aligned Start Points


NOTES

If the start points do not line up, the surface twists, as shown in thefollowing figure.

Figure 7: Unaligned Start Points Produce a Twisted Surface

Specifying Tangent Surfaces

You can make a blended surface tangential to the adjacent surfaces asshown in the following figure.

Blended surfacetangent to the

meshed surface

Figure 8

Blend Vertex

The each section of a blend must always contain the same number ofentities. If the sections do not have enough entities, you can add blendvertices. Each blend vertex adds one entity to the section. The followingfigure shows the smooth blending between two squares and a triangle.


NOTES

Figure 9: Adding a Blend Vertex

Swept SurfacesYou can create a swept surface by sweeping a sketched section along asketched or a selected trajectory.

Section Orientation

The sketching plane of the section orients itself normal to the trajectory, asshown in the following figure.

Section

Trajectory

Figure 10: Section Swept along a Trajectory

Figure 11: The Resultant Swept Surface


NOTES

Defining a Trajectory

You can define a trajectory by sketching it or by selecting datum curves orthe edges. As a general rule, the trajectory must have adjacent referencesurfaces or be planar. You can sketch or select a trajectory that has:

• Open curves or edges.

• Closed curves or edges.

• Non-tangent segments.

Figure 12: A Swept Surface with Non-Tangent Trajectory

Attributes of Swept SurfacesAdding Inner Faces

You can add inner faces while sweeping an open section along a closedtrajectory.

Figure 13: Sweeping an Open Section along a Closed Trajectory

Figure 14: Resultant Swept Feature without Inner Faces


NOTES

Figure 15: Resultant Swept Feature with Inner Faces

Attached or Unattached Surfaces

When you create a swept surface along an edge or a curve that is createdusing the edge, you may join the swept surface to the referenced quilt.

FLAT SURFACESYou can create a planar surface by sketching closed boundaries. Theboundaries may contain tangent or non-tangent segments.

Figure 16: Flat Surface


NOTES

USING SURFACES TO CREATE ADDITIONALSURFACES

Copying SurfacesYou can create a surface feature by copying the selected surfaces. Thecopied surfaces lies directly on top of the selected surfaces.

Selecting Surfaces

You can use following options to select the surfaces:

• Indiv Surfs – allows you to select individual surfaces.

• Surf & Bnd – allows you to define a seed surface and boundingsurfaces in order to select the surfaces.

• Loop Surfs – allows you to select the surfaces by defining loopsurfaces.

• Quilt Srfs – allows you to select a quilt.

• Solid Surfs – allows you to select all the surfaces of a solid part orassembly component.

Copying the solid surfaces of theprotruded solid to make a quilt

Resultant copied surface feature

Method 1: Selecting theIndividual surfaces

Seed Surface

BoundingSurface

Method 2: Selecting the surfaces usingSrf & Bnd option

Figure 17: Copying Surfaces Using Different Options


NOTES

Selection Options

• Excluding the Loops – you can exclude loops from the surfaces thatyou are copying using the Excld Loops option.

Excluding the leftsurface using ExcldLoops option

Cut feature

Figure 18: Copying Surfaces Using Excld Loops Option

• Filling the Loops – you can include the filled contours of the loopsfrom the surfaces that you are copying using the Fill Loops option.

Selecting a loopin order to selectthe entire surface

A solid surfaceselected bydefault

Figure 19: Copying Surfaces Using Fill Loops Option

Offset SurfacesYou can create an offset surface of a solid surface or a quilt usingfollowing options.

• Normal to Surface

• Auto Fit

• Controlled Fit

Offset features are discussed in detail in another module.


NOTES

LABORATORY PRACTICALGoal

In this exercise you create different types of simple surfaces.

Method

You complete a bottle model in which the middle portion is pre-constructed. You create the top and bottom portions using extruded, flatand blended surfaces. You use the swept option to finish the handleportion.

ToolsIcon Description

Saved View List

Use Edge

Done

EXERCISE 1: Creating the Handle and Top of aPlastic Bottle

Figure 20: Start Part and Complete Part


NOTES

Task 1. Open the partially built bottle and create a flat surface to close itfrom the bottom.

1. Open the BOTTLE_BASE.PRT and notice that the middle portion ofthe bottle is completed.

Figure 21: Start Part for Further Creation of the Surfaces

2. Click Insert > Surface > Flat.

3. Select the TOP datum plane to select the sketching plane. Confirmthe default direction and click Okay.

4. Click Right, then select the FRONT datum plane to select thereference plane.

5. Click Close to accept default sketcher references.

6. Click > Default.

7. Define a closed planar section to create a flat surface. ClickSketch> Edge> Use > Chain, then select two bottom edges asshown in the following figure. Click Next until you see all edgeshighlighted in blue, then click Accept.

Figure 22: Creating a Flat Bottom Surface


NOTES

8. Finish the sketch and surface creation. Click > OK.

9. Observe the new surface, rotate the model and notice the new flatsurface.

Figure 23: The Flat Surface

Task 2. Build the top portion of the bottle using a two-section blend.

1. Create a parallel blend for the top of the bottle using the existinggeometry. Click Insert> Surface > Blend > Done. Retain thedefaults Parallel, Regular Sec, Sketch Sec and click Done.

2. Specify the attributes. Retain the defaults Straight and Open Endsand click Done.

3. Specify the sketching plane. Click Make Datum > Through. Selectthe edge shown in the following figure and click Done. Ifnecessary, flip the feature creation arrow so that it points upwardand click Okay.

Figure 24: Specifying the Sketching Plane

4. Specify the reference plane. Click Top and select FRONT as thereference plane.


NOTES

5. Close the REFERENCES dialog box and click Yes to continuesketching.

6. Click View > Default Orientation.

7. Sketch the first section. Click Sketch > Edge > Use > Chain.Select the two edges as shown in the following figure.

Figure 25

8. Specify the chain of edges. Click Next until all edges arehighlighted in blue. Click Accept to select all edges.

Figure 26: Specifying the Chain of Edges

Tips & Techniques:

To use the Chain option, you must select two edgessimultaneously (edge of surface versus a datum curve).

9. Note the start point and toggle to the next section. Click Sketch >Feature Tools > Toggle Section. Note and confirm that the cyansection is now gray.


NOTES

10. Create the second section. Click Sketch > Edge > Offset. ClickChain, then select the same two edges used while sketching thefirst section.

11. To specify the chain of edges, click Next until you see all theedges highlighted in blue, then click Accept.

12. Specify the offset distance. Note the red arrow indicating thepositive direction. To make the second section larger than the first,

type [-0.50] and click .

13. Note the start point. If the two start points do not line up, select thecorrect vertex and click Sketch > Feature Tools > Start Point.

Figure 27: Aligned Start Points

14. Finish the sketch creation. Click .

15. Specify the depth. Retain the default selection Blind and click

Done. Type [0.375] then click .

16. Finish the surface creation. Click OK.

Figure 28: Blend Surface


NOTES

Task 3. You may continue to build the next surface using the Blendoption, but for this exercise use the Extrude option to build the nextsurface.

1. Click Insert > Surface > Extrude.

2. Retain the defaults One Side and Open Ends and click Done.

3. Create a sketching plane. Click Make Datum > Through. Selectthe edge of the blended surface and click Done.

4. Specify the view direction. If necessary, flip the feature creationarrow so that it points upward and click Okay.

Figure 29

5. Specify the reference plane. Click Right, then select FRONT.

6. Change the view. Click > Default.

7. Close the REFERENCES dialog box and click Yes to continuesketching.

8. Use the edge of the blended surface to define the section to

extrude. Click >Chain. Select two adjacent edges and clickNext until all the top edges are highlighted in blue. Click Accept.


NOTES

Figure 30

9. Finish the sketch. Click .

10. Specify the feature depth. Retain the default Blind and click Done.

11. Define the height of the extruded surface. Type [1], then click .


Figure 31: Bottle after Adding Surface Extrude Feature

Task 4. Create the next surface using parallel blend. For the firstsection, use the same edge that you used to create the surface extendfeature. Make the second section circular.

1. Create a parallel blend. Click Insert > Surface > Blend.


NOTES

2. Specify the options. Retain the defaults Parallel, Regular Sec, andSketch Sec and click Done.

3. Specify the attributes. Retain the defaults Straight and Open Endsand click Done.

4. Specify the sketching plane. Click Make Datum > Through, selectone of the longer edges on top of the bottle and click Done. UsingFlip, change the arrow direction so that it points upward and clickOkay.

Figure 32: Specify the Sketching Plane

5. Specify the reference plane. Click Bottom and select FRONT asthe reference plane.

6. Specify the sketcher references. Select FRONT and then RIGHT.Close the dialog box.

7. Change to the default view.

8. Sketch the first section. Click > Chain, then select two adjacentedges of the extruded surface.


NOTES

Figure 33: First Section of Blend Feature

9. Click Next until all edges are highlighted in blue, then clickAccept.

10. Note the start point and notice that the section has four segments.

11. Toggle to the next section and create the section. Click Sketch >Feature Tools > Toggle Section, then confirm that the cyansection is now gray.

Task 5. Sketch the second section as a circular section and split it infour segments.

1. If you have not already done so, click View > Sketch Orientationto return to the 2-D orientation.

2. Sketch a circle of 2.75 diameter.

3. Sketch two centerlines passing through the center of the circle, asshown in the following figure.

4. Using the centerlines, divide the circle in four segments. Click Edit> Trim > Divide and select on the circle at each of the four circle-centerline intersections.

5. Make sure the start points line up correctly.


NOTES

Figure 34: Sketch of Second Section

6. Finish the sketch. Click .

7. Define the depth. Retain the depth option Blind and click Done.

Type [1.00], then click .


Figure 35: Final Shape after Creating Second Blend Feature

Task 6. Create a cylindrical neck of the bottle.

1. Extrude a cylindrical surface from the opening of the previousblend with a blind height of 0.5. Click Insert > Surface >Extrude.


NOTES

2. Retain the default attributes One Side and Open Ends, then clickDone.

3. Specify the sketching plane. Click Make Datum > Through, selectthe top circle of the bottle, and click Done.

4. Specify the upward viewing direction and click Okay.

5. To specify the reference plane, click Bottom and select FRONT.

6. To specify the sketcher references, select RIGHT and FRONT.

7. Close the dialog box.


9. Sketch the section. Click . Copy the existing edges of the circle.

10. Finish the sketch and specify the blind depth. Type [0.5] and click

. The finished surface should look similar to the one shown inthe following figure.

Figure 36: Finished Top Portion of the Bottle

Task 7. Build the handle of the bottle, using Sweep. Before creating thesweep, create datum points to define the trajectory.

1. Create a datum point on the surface. Click Insert > Datum > Point> On Surface.


NOTES

2. Specify the surface and references. Select the meshed surfaceshown in the following figure. Click Done Sel.

3. Specify the two placement planes/edges for the dimensions. SelectFRONT and TOP. Type [0.0] for the FRONT reference and type[11.25] for the TOP reference.

4. Finish the point creation and click Done.

Figure 37: Creating the Datum Points for Handle

Task 8. Create a datum curve by using the datum points and define thestart and end tangency condition.

1. Create a datum curve through points. Click Insert > Datum >Curve > Thru Points > Done.

2. Specify the curve points. Retain the defaults Spline, Whole Array,and Add Point. Select the top datum point that you created, thenselect the PNT1 and click Done.

3. Define tangency conditions at the endpoints. Click Tangency >Define in the dialog box.

4. Create the curve tangent to an axis passing it through the upperpoint and perpendicular to the surface. Retain the defaults Startand Tangent, then click Create Axis > Pnt on Surf.

5. Define the point. Select PNT2, then click Done Sel > Done.

6. Specify the tangency direction, as shown in the following figure.Click Okay.


NOTES

Figure 38

7. Make the end of the curve as tangent to the lower surface. Retainthe defaults End and Tangent, then click Surface. Select thelower surface below the datum point PNT1, shown as meshed inthe following figure.

8. Finish creating the datum curve. Click Done/Return > OK.

Figure 39

Note

It is good practice to create a datum curve as the trajectory of asweep because you can abort the creation of the sweep and stillhave the curve available


NOTES

Task 9. Build the bottle handle using the Sweep option. Use the curvethat you created as the trajectory.

1. Create a swept surface. Click Insert > Surface > Sweep > SelectTraj.

2. To specify the trajectory, retain the defaults One By One andSelect. Select the datum curve that you created previously, thenclick Done Sel and Done.

3. Accept the default direction and click Okay.

4. To specify the attributes, retain Open Ends and click Done.

5. Accept the default sketcher references and close the dialog box.

6. Sketch the section as shown in the following figure. You may needto use a sketched point to line up the sketch to the start point of thetrajectory.

Figure 40: Section of the Handle

7. Finish the sketch and the feature creation. Click > OK.


NOTES

Figure 41: The Completed Bottle

8. Save the model, close all windows and click File > Erase > NotDisplayed > OK.


NOTES

MODULE SUMMARYIn this module, you have learned that:

• Pro/ENGINEER creates simple surfaces similar to the way solids arecreated.

• Unlike solid features, surface features allow the user to add tangencyand curvature constraints.

• Multiple surfaces can be joined to create larger complete surfaces.

• You can copy solid surfaces to create a surface feature.

Page 3-1

Module

Geometry for Surfaces: Points & CurvesDatum points and datum curves are the building blocks of surface

features. In this module you learn to create points and datum curves.

Objectives


• Define and create datum points using various options.

• Define and create datum curves using various options.

• Define and create sketched splines and conics.


NOTES

DATUM POINTSDatum points are used to specify loads for mesh generation, attach datumtargets and notes, create coordinate systems and pipe trajectories. Whilecreating surfaces, you use datum points to:

• Create datum curves.

• Locate coordinate systems, datum planes, and datum axes.

• Define variable radius rounds.

• Specify the position of a sweep cross-section along a trajectory.

Creating Datum PointsTo create datum points, you can use all of following options:

• On Surface

• Offset Surf

• Curve X Srf

• On Vertex

• Offset Sys

• Three Srf

• At Center

• On Curve

• Crv X Crv

• Offset point

• Field Point

• Sketch

On Curve

You can create points on a curve or an edge using one of the followingoptions to locate the point on the curve:

• Offset – Dimensions the point to a planar surface.

Figure 1: Point on Curve Offset from a Planar Surface

Geom et ry for Surfaces: Points and Curves Page 3-3

NOTES

• Length Ratio – Expresses the distance from the point to the curvevertex as a ratio of the total length of the curve, shown in the followingfigure as a fraction in decimal form.

Figure 2: Point on Curve as Length Ratio

• Actual Length – Dimensions the point by measuring a specificdistance from the vertex of the curve.

On Surface

You can create points on a surface by dimensioning it with respect to twodatum planes or edges.

Figure 3: Points on Surface Dimensioned to Two Datum Planes

On Vertex

You can create points on the vertex of a part edge, surface feature edge,and ends of a datum curve.

Figure 4: Points on Vertex


NOTES

Note

When creating surfaces from points and curves, you shouldalways consider the level of complexity. If you create a surfacefrom curves through points, those original points subsequentlycontrol and dimension the surface, which could make itdifficult to change later.

DATUM CURVESDatum curves play an important role while creating surfaces. You can usethem to define:

• Trajectories for sweeps or blends

• Boundaries of blended surfaces

Creating Datum CurvesTo create datum curves, you can use the following options:

• Sketch

• Intr. Surfs

• Thru Points

• From File

• Composite

• UseXsec

• Projected

• Formed

• Split

• OffsetFromSrf

• From Curve

• FromBoundary

• Offset Curve

• 2 Projections

• From Equation

Sketched Datum Curves

You can create planar curves using the sketcher. Sketched curves canconsist of one or more sketched segments and of one or more open orclosed loops. As you sketch the datum curves, Pro/ENGINEER creates asingle composite datum curve on top of discrete sketched datum curvesegments.


NOTES

Sketching Splines and ConicsWhile creating free form or style surfaces, you are often required to sketchsplines and conic curves.

Sketched Splines

A spline consists of a series of points through which a smooth curvepasses.

Figure 5: Spline through a Series of Points

Defining Tangency

A spline can be sketched free form or its endpoints can be defined tangentto existing geometry. You can apply tangency constraint or provide aspecific angle to define end point tangency, as shown in the followingfigure.

Figure 6: End-Point Tangency


NOTES

Dimensioning Splines

• You can use tangent vector angles to dimension a spline. You candefine the vector angles for the end points and the intermediate points.

Figure 7

• You can define the linear dimensions to locate the endpoints or anyintermediate points, as shown in the following figure.

Figure 8

• To define the tangency at the endpoints, you can specify the radius oftangency. To control the curvature of a tangent, you can change theradius of curvature, as shown in the following figure.

Figure 9


NOTES

Modifying Spline Shapes

To modify the shape of a spline, you can:

• Move internal points.

• Display the curvature plot.

• Add or delete points.

Figure 10: Modifying an Existing Spline

• Enable control points in order.

Figure 11: Enabling Control Points

• Reduce number of points using the Sparse option.

• Smooth the shape using the Smooth option.


NOTES

Sketched Conics

You can sketch a conic entity with three points, two endpoints and anintermediate point. The shape of a conic is controlled by the shape factorrho, as shown in the following figures. If you increase the value of rho,the peak of a conic becomes sharper.

The values of rho are:

Ellipse 0.05 < rho < 0.5

Parabola rho = 0.5

Hyperbola 0.5 < rho < 0.95

Figure 12: Rho Value Defines a Conic

Figure 13: Sharper Peak with Higher Value of rho


NOTES

Defining Curves through the PointsYou can create a curve through a series of datum points. You can also useedge vertices and the end of the curves as the through points.

The system offers three choices to create a curve through the selectedpoints:

• Spline – Creates a 3D spline passing through the points.

• Single Radius – Creates a curve using the same radius through all thebends.

• Multiple Radius – Creates a curve by specifying a radius for eachbend.

Defining End Conditions

When you create a curve using the Thru Points option, you can make itnormal or continuous to the edge, curve, surface or an axis on which thepoint is lying.

The Thru Points option is a very useful in creating boundaries of blendedsurfaces, as shown in the following figure.

Figure 14: Blended Surface Boundaries

Attaching Curves to a Surface

When you create a Thru Points curve, you can modify its attribute tomake it lie on a surface, as shown in the following figure.


NOTES

Figure 15: A Thru Points Curve attached to a Surface

Modifying the Shape of the Curve

You can modify the shape of the curve by manipulating it in a 3D space oron a specific surface. While modifying the curve a number of curveanalysis tools are also available to you. If you tweak a curve, the systemmaintains the tangency conditions that you assigned at the ends of thecurve, as shown in the following figure.

Figure 16: Tangency Conditions


NOTES

Creating Curves from FilesYou can import datum curves from a special ASCII file with a .IBL fileextension, or from an IGES file using a coordinate system as a reference.Pro/ENGINEER treats the curve as one feature, however, for practicalpurposes, you can select the datum curves separately (for example, forblending surface features). Two points in a section define a straight line,whereas more than two define a spline.

open

arclength

begin section ! 1

begin curve

1 20 30 40

2 40 50 70

3 30 60 80

begin section !

begin curve

1 30 60 80

2 40 70 40

Indicates creation of an open ended curve.[closed] would appear for a loop curve,with first and last points coincident.

Indicates method of internal referencing assection arc length. [pointwise] appears forpointwise referencing; such sections must all havethe same number of points.

Each section defines oneentity within the datumcurve feature.

Note that last and firstpoints of adjacententities are coincident,providing featurecontinuity.

Figure 17: Sample: IBL File and File Terminology


NOTES

Redefining the From File Curves

Pro/ENGINEER allows you to redefine the curves that are read from afile. You can use following options to redefine them:

• Edit file – Allows you to manually edit the points.

• Create – Adds additional curves.

• Spline Pnts – As an alternative to manually changing the curves withthe Edit File option, assists the adjustment process.

� Sparse – Reduces the number of points.

� Smooth – Makes the spline smoother.

� Add – Adds points to increase the control.

� Remove – Allows you to remove points individually.

� Move – Allows you to move spline points.

� Show – Displays the points along a spline.

� Blank – Turns off the display of points along a spline.

• Adjust – Adjusts two curves so that they intersect.

• Trim/Extend – Trims or extends a curve up to a surface.

• Split – Splits one curve into two curves.

• Merge – Merges two curves into one.

• Delete – Deletes curves from the feature.

• Measure – Accesses the INFO CURVE menu for calculations.

Composite Datum CurvesYou can combine datum curves using part edges and surface feature edgesto create a composite curve.

Use composite curves to:

• Remove small surfaces from the design

• Create a single surface with continuous curvature

• Attain better surface aesthetics.


NOTES

Figure 18: A Boundary Surface with Multiple Curves

Figure 19: A Boundary Surface with Composite Curves

Type of Composite Curves

• Exact – Creates a composite curve that exactly follows the originalcurves and edges.

• Approximate – Creates a composite curve that approximates a chainof tangent (C1 continuous) curves by a single continuous curvature(C2 continuous) spline.

Projected CurvesYou create datum curves by sketching a section, or selecting an existingdatum curve, and then projecting it onto one or more surfaces.

You can project datum curves onto solid surfaces, a set of non-solidsurfaces, quilts, or datum planes.


NOTES

Formed CurvesA formed datum is a projected curve that preserves the length of theoriginal curve. To understand the concept of a formed curve, consideryour curve to be a piece of thread. If you drop the thread on a non-planarsurface, it will reflect the shape of the surface, but its length will notchange.

You project the sketched or selected curve normal to the surface or along adirection.

Figure 20: Projected Versus Formed Datum Curve

From EquationYou can create a datum curve from an equation. You need to define thefollowing parameters while creating a curve from an equation.

• Coordinate System (Csys)

• Coordinate System Type (Csys Type) – Specify the type of thecoordinate system specify the type of the coordinate system. Theoptions are Cartesian, Cylindrical, and Spherical

• Equation – Enter an equation in an editor. The equation is specified interms of parameter T, which varies from 0 to 1, and three coordinatesystem parameters: X, Y, and Z for Cartesian, r for Theta, Z forCylindrical, and phi for Spherical.


NOTES

From BoundaryYou can create a datum curve that is offset from a surface boundary. Youcan select an edge and define the offset distance from the end points of theedge. You can specify the offset distance either normal to the boundary oralong the edge.

Figure 21: Datum Curve Offset from Boundary

Offset from SurfaceYou can create an offset curve from a curve that is lying on a surface. Theshape and the distance of the offset curve are controlled by a graph.

Figure 22: Curve Offset from Surface


NOTES


In this laboratory you create datum points and curves that are useful in

defining surface features.

Method

In the first exercise, you create a datum curve using the From Equationoption. You create a surface using the curve, then additional datum curvesusing the surface.

In the second exercise, you create the network of splines and conicsneeded to create blended surfaces of remote entry housing.


Saved View List

Create Spline through points

Select

Mirror Entities

Insert Datum Curve

Orient the Sketching Plane Parallel to Screen

Insert Datum Point

Create a Conic Arc

Done


NOTES

EXERCISE 1: Creating Datum Curves

Task 1. Create a new part and create a datum curve using an equation. .

1. Click File > New, then type [DATUM_CURVES] as the name andclick OK.

2. Click Insert > Datum > Curve > From Equation > Done. Selectthe PRT_CSYS_DEF coordinate system, then click Cartesian.

3. Input the equation. Notice that the editor opens to enter theequations. Type the following lines in the text editor window at thebottom of the file.

x = t * 10

y = 3 * sin(t * 360)

z = 0

Figure 23: Text Editor

4. In the NOTEPAD window, click File > Exit.

5. Click Yes to save and exit.

6. Finish the curve creation and click OK.


NOTES

Figure 24

Task 2. Create a swept surface first, then create a datum curve from itsboundary.

1. Click Insert > Surface > Sweep > Select Traj.

2. Retain the defaults One by One and Select. Select the curve, thenclick Done Sel >Done.

3. Click Okay to accept the default direction of the reference plane.

4. Define the ATTRIBUTES. Accept the default Open Ends andclick Done.

5. Accept the default Sketcher references and close the dialog box.

6. Sketch a single vertical line, as shown in the following figure.

Figure 25


NOTES

7. Click > OK to finish the sketch and surface creation.


Figure 26: The Swept Surface

9. To create a boundary datum curve, click > From Bndry >Done.

10. Select the boundary. Retain the defaults One By One and Select.Select the front sine wave-shaped edge of the swept surface, thenclick Done Sel > Done.

Tips & Techniques:

If you select the wrong edge, you can use Unselect.

11. Specify the left vertex offset:

� Retain the default Sel Pnt/Vert and select the left vertex tospecify its offset.

� Retain the options Specify Dist and Norm to Bnd. ClickAccept.

� Type [2.0], then click .

12. Specify the right vertex offset.

� Retain the default Sel Pnt/Vert and select the right vertex.

� Retain the options Specify Dist and Norm to Bnd. ClickAccept.

� Type [0.5], then click .


NOTES

13. Complete the feature. Click Done/Return>Done Extend.

Figure 27

Task 3. Create a datum curve that is offset from the surface. Also, createa graph to control the offset distance.

1. Click Insert > Datum > Graph. Type [OFFSET] and click .

2. Sketch the section, as shown in the following figure. Remember toadd the Sketcher coordinate system.

Center lines

Sketched coordinate system Single Line section

Figure 28

3. Finish the graph creation. Click .


NOTES

4. Click > OffsetFromSrf > Done.

5. Select the curve from which to offset. Select the boundary datumcurve that you just created in the previous task.

6. Specify the start point at the left side of the curve, and then clickOkay.

7. Select the swept surface to specify the surface from which tooffset.

8. Define the direction, as shown in the following figure, then clickOkay.

Figure 29

9. Specify a datum graph for the offset value. Click Sel By Menu. Inthe SELECTION TOOLS dialog box, select OFFSET. Click Select.

10. Specify the scale. Type [1.0], then click .

11. Observe the Offset curve in the FRONT view. Click > FRONT.

Figure 30: Offset from Surface Datum Curve


NOTES


Task 4. Create a datum curve by projecting it onto the surface that youcreated earlier. Also, form a datum curve onto the surface and compare theresults.

1. Click > Projected > Done > Sketch > Done.

2. Set up a sketching plane. Click Make Datum > Offset. SelectTOP.

3. Define the offset value. Click Enter Value. Type [5], then click

> Done.

4. Click Okay to accept the default viewing direction.

5. Make sure that the arrow, showing direction for projecting thesketch, points towards the surface, and then click Okay.

6. Click RIGHT and select RIGHT as the reference plane.

7. Accept the default sketch references and close the REFERENCESdialog box.

8. Sketch a circle, as shown in the following figure.

Figure 31

9. Click to finish the sketch creation.

10. Return to the default view.


NOTES

11. Specify the projection surface. Retain the defaults Surfaces >Include > Indiv Surfs. Select the surface, then click Done Sel>Done.

12. Specify the projection type. Click Norm to Sket > Done.

Note:

The second option, Norm to Surf, projects the sketch normalto the selected surface.

13. Click OK from the dialog box to finish the curve creation.

Figure 32: Projected Curve

Task 5. Create a datum curve by forming it onto the surface that youcreated earlier.

1. Click Insert > Datum > Curve > Formed > Done. Click QuiltSurfs to form the sketch on a surface feature.

2. Specify the sketching and reference plane. Click Use Prev so thatthe system uses the previously selected sketching references.


4. Confirm that the arrow showing direction of feature creation pointstowards the surface, and then click Okay.

5. Accept the default sketcher references and close the dialog box.


NOTES

6. Sketch the section, as shown in the following figure. Be sure toinclude the Sketcher coordinate system in the center of the circle;this coordinate system is required for a formed curve.

Figure 33

7. Click to finish the curve creation.

Figure 34: Result of Formed and Projected Datum Curve

Task 6. (Optional) Measure the perimeter of the formed curve toconfirm that it is equal to 2πr, the circumference of the projected circle.

1. Measure the curve length of half of the formed circle. ClickAnalysis > Measure. If necessary, click Curve Length from theTYPE drop-down list in the MEASURE dialog box.

2. Select one-half of the formed datum curve. Note that the lengthindicated in the RESULTS area of the dialog box is pi. Close thedialog box.

3. Save the model and erase it from memory.


NOTES

EXERCISE 2: Creating Curves to Build Surfaces

Figure 35: Completed Model Based On Curves

Task 1. Create a new part and begin curve creation.

1. Click File > New, then type [remote_entry] as the name and

click .

2. Click > Sketch > Done.

3. Select TOP as the sketching plane. Click Okay to accept thedefault direction.

4. Click Bottom, then select the FRONT datum plane.

5. Click Close to accept the default sketcher references.

6. Sketch a vertical centerline through the RIGHT datum plane, andzoom in to approximately four grid squares

7. Click to sketch spline. Select the first point on the centerline.Select the second point so that the curve is approximatelyperpendicular to the centerline. Continue to select the points.Create a shape, as shown in the following figure. Middle-click tofinish the spline.


NOTES

Figure 36: Initial Spline

8. Dimension the end points, as shown in the following figure.

Figure 37

9. To modify the shape of the spline, click , then select the spline.Right click Modify. This opens the MODIFY SPLINE dialog box.

10. To move the points, click a point, drag it to the desired locationand click again.

11. Add and delete the points as necessary.

12. Close the dialog box when finished.

13. Click , select the spline. Click , select the centerline to mirrorthe existing spline.

Figure 38


NOTES

Tips & Techniques

While working with spline create as few points as possible todefine the desired shape.

Task 2. Create another spline.

1. Click . Start a new spline at left endpoint of the existing spline.

Figure 39

2. Constrain it as tangent to the first spline.

3. Click , and double-click the spline. Move the points to refinethe shape.

4. Click . Start a new spline at the endpoint of the previous spline.Select the second point so that it is tangent to the previous spline.

5. Dimension the end point so that it is normal to the centerline, asshown in the following figure.


NOTES

Figure 40: Spline Creation

6. Click , and double-click the spline. In the MODIFY SPLINEdialog box, click Display Curvature spline.

7. In the Scale textbox, enter [100].

8. Click Move and refine the shape of the spline, as shown in thefollowing figure. Close the dialog box when finished.

Figure 41: Spline with Curvature Display

9. Click , press and hold <SHIFT> and select the last two splinescreated.

10. Click , and select the centerline. The curve should look similarto that shown in the following figure.


NOTES

Figure 42: Final Sketch

11. To finish the sketch, click > OK.

Figure 43: Finished Curve.

Task 3. Create another datum curve perpendicular to the TOP datumplane to allow creation of the top surface of the remote housing.

1. Click > Sketch > Done.

2. Select FRONT as the sketching plane. Click Okay to accept thedefault direction.

3. Click Top and then select the TOP datum plane.


NOTES

4. In the REFERENCES dialog box, select F2 (TOP) and clickDelete.

5. Rotate the model to the default orientation, and select the portionsof the existing curve that intersects FRONT, as shown in thefollowing figure. Close the REFERENCES dialog box whenfinished.

Figure 44: Selecting References

6. Click to return to the sketch view.

7. Create a centerline through RIGHT.

8. Sketch a horizontal line offset from the curve, and symmetricabout the centerline.

Figure 45: Horizontal Symmetric Line


NOTES

9. From the ARC fly-out icons, click . Create two conics startingon the datum curve and tangent to the end points of the horizontalline, as shown in the following figure.

Figure 46: Creating Conics Tangent to Line

10. Finish the sketch by clicking > OK.

Task 4. The second datum curves will be created perpendicular to theTOP datum using datum points.

4. Click > On Vertex > Query Sel. Select at the approximateintersection of the uppermost splines, as shown in the followingfigure. When highlighted, click Accept > Done Sel.

Figure 47: Modifying Spline Shape

5. Click On Vertex > Query Sel. Select the opposite vertex of thesplines. When highlighted, click Accept > Done Sel > Done>Done. You should see two points, as shown in the followingfigure.

Figure 48: Point Creation


NOTES

6. Click > Thru Points > Done.

7. Select the two points. Click Done.

8. Click Tangency > Define > Surface > Normal. Select the TOPdatum plane and click Okay.

9. Click Surface > Normal. Select the TOP datum plane.

10. Click Flip > Okay > Done/Return> OK.

Figure 49: Second Curve

Task 5. Build the final curve by creating a datum that passes through thevertices of the splines.

1. Click > Sketch > Done >Make Datum > Through. Click allthe options except Point/Vertex so that they are not highlighted.

2. Click Query Sel. Select the vertex of the lower spines. ClickAccept.

3. Click Through, then click all the options except Point/Vertex sothat they are not highlighted. Click Query Sel, select the oppositespline vertex, and click Accept.

4. Click Parallel, select the FRONT datum plane and click Done.Accept the default viewing direction, click Okay.


NOTES

Figure 50

5. Click Top, then select the TOP datum plane.

6. Reorient the model to the default orientation, and select the datumcurve endpoints as additional references. Close the REFERENCESdialog box.

7. Click to return to the sketch view.

8. Click . Start a new spline starting and ending on the verticesselected as references. Sketch the spline slightly smaller than theprevious curves, as shown in the following figure.

Figure 51: Third Spline

9. Click , and double-click the spline. In the MODIFY SPLINEdialog box, click Control Points. Drag the white control points todefine a shape similar to that shown in the following figure. Closethe MODIFY SPLINE dialog box.


NOTES

Figure 52: Spline with Control Points

10. To finish the sketch, click > OK.

Task 6. Mirror the curves.

1. Click Feature > Copy > Mirror > Dependent > Done.

2. Select the three uppermost datum curves. Click Done Sel > Done.

3. Select TOP as the mirror plane, and click Done.

4. You should have a curve network similar to that shown infollowing figure.

Figure 53: Final Curve Network



NOTES


• You can create datum curves using various options.

• Splines can be modified in using several methods.

• Datum points are useful to define and create datum curves.

• You can create datum curves and splines using different options thatare particularly useful while creating surfaces.

Page 4-1

Module

Manipulating SurfacesIn this module you learn to manipulate and join surfaces to create a

quilt.

Objectives


• Merge surfaces.

• Manipulate the surfaces using the Extend and Trim options.

• Manipulate the location of a surface using the Transform andMove options.

• Create a copy of a surface.


NOTES

Pro/ENGINEER enables you to manipulate the surfaces by:

• Extending the surfaces.

• Trimming the surfaces.

• Transforming the surfaces.

• Merging the surfaces.

Extending SurfacesYou can extend the surfaces on a model to avoid gouging a part duringmanufacturing, or to successfully merge surfaces. You create new surfacesby extending the one-sided edges of existing surface features.

Using the following options, you can create the extend feature of a surfaceor an approximate surface along a specified direction, or tangent to itsparent surface:

• Same Srf – Creates the extend feature using the same surface beingextended, continuing the original surface past its original edge by aspecified distance.

Figure 1: Extending Surfaces using the Same Srf Option

• Approx Srf – Creates an extension as a boundary blend. This methodis useful for extending the surface up to a vertex that does not lie alonga straight edge, or for extending imported surfaces that may have beenpoorly created in other systems (for example, when surfaces have highcurvature or bad vertices).

Manipulat ing Surfaces Page 4-3

NOTES

• Along Dir – Extends the surface edge in a direction normal to aspecified terminating plane (valid only if used with the Up To Planeoption).

Figure 2: Extending Surface with the Along Dir Option

• Tangent Srf – Creates the extended surface feature tangent to itsparent surface.

Figure 3: Extending Surface with Tangent Srf Option


NOTES

Specifying the Surface Extension DistanceYou can specify the surface extension distance as:

• Single – making the distance the same for all selected edges.

• Variable – by specifying different extension distances for selectedvertices or datum points on the edge. You can measure the surfaceextension along the cord surface being extended, normal from aselected plane or datum plane to the extension surface, or up to aspecified terminating plane (any planar surface).

Figure 4: Specifying Surface Extension Distances

Note:

You can only measure the surface extension up to a specifiedplane if you use both Up To Plane and Along Dir.


NOTES

Extending EdgesTo extend an edge, you use the following options:

• Extending the Side Edge – A side edge is created as an extension ofthe surface’s side edge.

The extended surface

Side edge

Side edge

These edges areextension of the sideedges

Figure 5: Extending Side Edges

• Normal to Boundary – A side edge is extended normal to theboundary.

Boundary

These edgesare normal tothe boundary

Figure 6: Extending Side Edge Normal to Boundary


NOTES

Trimming SurfacesYou use the trim feature to remove portions of an existing surface feature.A trim feature is similar to a solid cut. You can trim a surface or a quiltusing any of the following feature creation options:

• Extrude, Revolve, Sweep, and Blend – Cuts a piece from an existingsurface feature by creating a sketch and using one of these forms.

• Use Quilts – Cuts a piece from a surface using an intersecting quilt.Pro/ENGINEER consumes the quilt that is used to trim a surface andallows you to keep either or both sides of the trimmed surface, asshown in following figures.

Trimming Quilt

Figure 7: Trimming a Spherical Surface with a Quilt

Figure 8: Two Possible Results of Trimming


NOTES

• Use Curves – Trims a surface using selected curves and edges.

• Vertex Round – Trims a surface by rounding or filleting selectedvertices.

Figure 9: Rounding Selected Vertices

• Silhouette – Trims a surface at its silhouette edge from a specifieddirection.

• Advanced – Trims a selected surface using boundaries, swept blends,etc.

Transforming SurfacesYou use the Transform option on datum curves, surfaces, and mergedsurfaces to:

• Translate

• Rotate

• Mirror

• Flip the Normals of a Surface

Copy vs. Transform

While moving (translating or rotating) or mirroring an entity, you have theoption to create a copy of the selected entity. Instead of transforming thegeometry, you can copy it and make the copied geometry independent ofthe original.

In contrast, you cannot make transformed geometry independent of theoriginal, but the duplicated transformed geometry does not regenerate,which offers you the advantage of decreased regeneration time.


NOTES

SelectTranslate and

Copy

Select thissurface

Select this coordinate

Figure 10: Transform Option with Translate and Copy

Merging SurfacesYou can merge two adjacent or intersecting quilts. The resulting quilt is aseparate feature, coincident with the two original quilts. There are twooptions you can use to merge the quilts:

• Intersect – Attaches the two intersecting quilts.

• Join – Merges two adjacent quilts by aligning the edges of one quilt tothe surfaces of the other.

Join Intersect

Resultant Merge

Figure 11: Using Merge Join and Merge Intersect


NOTES

While merging the intersecting surfaces, you can specify which portion ofthe quilt to include in the merge feature by selecting Side 1 or Side 2 foreach of the quilts.

Figure 12: Four Options to Merge Two Intersecting Surfaces

Parental Hierarchy of Quilts

When you merge two or more quilts, you can define the parental hierarchyof the quilts. The primary quilt becomes the parent quilt. The additionalquilt is merged with the primary quilt.

The parental hierarchy determines how the quilts are controlled by theRedefine and Delete options.


NOTES


In this laboratory you extend, trim, and transform model features in

order to complete the model. You merge the model surfaces to create a

single quilt.

Method

In this exercise, you complete a mouse model. The initial style surfaces ofthis model are created using another program and are incomplete. Youmanipulate the imported surfaces to complete the model using varioussurface manipulation tools.


Saved View List

Done

EXERCISE 1: Manipulating Surfaces

Figure 13: Model at Start and Finish


NOTES

Task 1. Open and examine the mouse model.

1. Open MOUSE.PRT.

2. Observe the model. Rotate the model to notice it is incomplete andthe surfaces do not intersect each other. Also, notice there are threeimported surfaces. Examine the Model Tree.

3. Click > View2 to change the view.

Figure 14: The Incomplete Surfaces

Task 2. Extend the top cover surface tangentially.

1. Click Insert > Surface Operation > Extend. Retain the defaultVariable and Dist On Srf, and click Tangent Surf > Done.

2. Select the edge shown in the following figure, and then clickDone.

Figure 15

3. Retain the default Sel Pnt/Vert, and then select the first vertex, asshown in the following figure.


NOTES

Figure 16

4. Retain the defaults Specify Dist and Norm to Bnd, and then click

Accept. Type [10] and click .

5. Retain the default Sel Pnt/Vert, then select the second vertex.

6. Retain the defaults Specify Dist and Norm to Bnd, and then click

Accept. Type [2] and click .

7. To complete the action, click Done Sel > Done Return.

8. To specify the side edge direction, accept the default ExtSideEdgeand click Done.

9. To specify the second side edge direction, accept the defaultExtSideEdge and click Done.

10. Click Done Extend to complete the surface extension.

Figure 17: Completing Surface Extension

11. Observe the extended surface and notice that the extended surfaceis another surface patch.


NOTES

Task 3. In order to extend the side-wall, merge the two surfaces patchesand make it a quilt.

1. Click Insert > Surface Operation > Merge > Join. Select any oneof the surface patches, shown as meshed in the following figure,

and then select the second surface patch. Click .

Figure 18

2. Observe the merged surfaces. Notice that the common edge hasturned magenta, signifying that the surfaces have merged.

Task 4. Extend the merged quilt using the Same Srf option.

1. Click Insert > Surface Operation > Extend. Retain the Same Srfand Dist on Srf options, and then click Single Dist > Done.

Figure 19: Extending Merged Quilt

2. Click Tangent Chain, and then select the edge, as shown in thepreceding figure. Click Done.

3. Select the same edge to measure the distance from. Type [10] and

click .

4. Specify the extension attributes of the first edge, retain the defaultExt Side Edge, and click Done.


NOTES

5. Specify the extension attributes of the other edge, retain the defaultExt Side Edge, and click Done.

6. Complete the surface extension. Click Done Extend.

Figure 20

7. Observe the model. Notice that the Same Srf option does notcreate a separate patch while extending a surface.

Task 5. To accommodate a design change in the internal packaging,move the side wall surface away from the mid-plane.

1. Move the surface. Click Insert > Surface Operation > Transform> Move > No Copy > Done. Select the side wall surface, and thenclick Done Sel.

2. Click Translate, and then select the TOP datum plane.

Figure 21

3. Click Okay to accept the default direction, as shown in thepreceding figure.

4. Define the translation value. Type [3], and then click .

5. Click Done Move to finish the translation.


NOTES

6. Observe the model to notice the gap generated because oftranslation.

Figure 22

Task 6. Extend the side wall edges to the mid- plane so that there is nogap when you mirror the model.

1. Extend the first edge of the surface. Click Insert > SurfaceOperation > Extend > Along Dir > Done. Select the edge shownin the following figure, and then click Done Sel > Done.

Figure 23

2. Select the TOP datum plane, and then click Done Extend to definethe plane.

3. Extend the other edge using the method outlined in previous steps.


NOTES

Figure 24

Task 7. Now that the top cover surface and the side wall quilt intersect,merge them to make a single quilt.

1. Click Insert > Surface Operation > Merge > Intersect. Select thetop quilt, and then select the side wall quilt.

Figure 25: Merging Top and Side Wall Quilts

2. Select the quilt sides to retain. If not already selected, click Side 1for both the primary and additional quilt. The model should displayas shown in the preceding figure.

3. To finish merging click .

Task 8. For mold release, trim away the portion of the side-wall that isbending towards inside and then extend the surface normal to the FRONTdatum plane.

1. Observe the model in shaded mode to notice the bending-inportion.


NOTES

Figure 26:

2. Trim away the bending-in portion. Click Insert > Surface Trim >Silhouette > Done.

3. Select the side-wall quilt.

4. To define the viewing plane, select the FRONT datum plane.

Figure 27

5. Click Side1 > Done to select the side to retain.

6. Click Preview to see how the surface is being trimmed, and thenclick OK to finish creating the feature.

7. Extend the trimmed edge up to the FRONT datum plane using themethod outlined in the previous steps.

Figure 28


NOTES

Task 9. (Optional) Complete the top cover of the mouse model bymaking a mirror copy and merging the quilts.

1. Using Transform > Mirror Copy, mirror the quilt about the TOPdatum plane.

2. Merge the quilts.

3. Create a fillet to round off the top intersecting edge.

Figure 29: The Final Quilt

4. Save and erase the model from the memory.


NOTES


• You can extend or trim Pro/ENGINNER surface features or importedsurfaces in order to manipulate their size and shape.

• You can translate or rotate a surface feature using the Transformoption.

• You can mirror a surface feature about plane using the Mirror option.

• While you transform a surface, you can transform the base geometryitself or create a copy of it.

• You can merge adjacent or intersecting surfaces to create a quilt.

Page 5-1

Module

Modifying Solid Surfaces Using QuiltsIn this module you learn how to use quilts in order to manipulate

and define the complex shapes of the solid features.

Objectives


• Define and create Surface Replace features.

• Define Surface Patch features.

• Define and create a cut in a solid object using a quilt.


NOTES

USING QUILTS TO MANIPULATE SOLIDSThere are many ways you can use quilts to manipulate the solid geometry.You can:

• Replace a solid surface with a quilt.

• Create a Patch feature.

• Create Cuts using quilts.

REPLACING SURFACESYou can replace a solid surface with a datum plane or a quilt.

Figure 1: Replacing A Solid Surface with a Quilt

Keeping the Quilt

By default, when you replace a solid surface by a quilt, the quilt isconsumed. If you want to retain the quilt, you can select Keep Quilt.

Restrictions and Requirements of Replace

• If surface replacement adds material in some places and removes it inothers, then the replacing quilt must consist of one surface only.

• It is not recommended to create two replacement features on top ofeach other. It is a good practice to delete one replacement quilt beforecreating a new one, or to redefine the existing replace feature so itreplaces a different surface or uses a different quilt.

Modi fy ing So l id Surfaces Using Qui l t s Page 5-3

NOTES

• For correct surface replacement, make sure the quilt extends to orbeyond the part boundaries. If this requirement is not met,Pro/ENGINEER will attempt to extend the quilt to intersect the partboundaries as shown in the following figure.

Figure 2

PATCHINGWith patching, you can replace a portion of a surface or multiple surfaceswith a single quilt, as shown in the following figure. The Patch optionallows you to add and remove material in a single operation. To create apatch feature, all the boundaries of the replacement quilt must lie on thesurfaces being patched.

SolidA surface lying on thethree solid surfaces

Resulting solid from the Patchoperation

Figure 3


NOTES

USING QUILTS TO CUT SOLIDSYou can create cuts using the commands Cut, Use Quilt. This is usefulwhen creating the complex shaped cuts that you cannot achieve by usingthe other standard options available for the Cut feature.

Resultant Solid - If thetop portion is retained

Resultant Solid - If thebottom portion is retained

Figure 4

Comparing Replacing and Cutting

While defining complex shapes of solids, you will come across certainsituations where you can either use the Cut tool or use the SurfaceReplace. While making the selection for the appropriate tool, you maykeep following in mind:

• Surface Replace allows you to retain the quilt if necessary.

• To cut the solids that are not completely intersecting the cutting quilt,you first need to add the material in the solid and then use the Cut tool.Whereas Surface Replace would add and subtract the material in oneoperation as shown in the following figure.

Solid part with surfacefeature

Cut createdusing thesurface feature

Surfacereplacement

Figure 5: Replacement versus Surface Cut


NOTES


In this laboratory, you will manipulate the shape of the solid features

using the Replace and Cut features.

Method

In the first exercise, you use the replace functionality to force a stiffener tofollow a complicated fuselage shape. You also use the replacefunctionality to create a rib feature that follows the shape of the surfacefeatures.

In the second exercise, you create a quilt then cut the solid using the quilt.


Saved View List

Build Feature

Done


NOTES

EXERCISE 1: Creating a Stiffener and a Rib forFuselage

Task 1. Open and observe the model.

1. Open STIFFENER PART.

2. Notice the complex fuselage surfaces of the upper and the lowersections.

Figure 6: The Fuselage Sections

3. To resume the solid stiffener, click Feature > Resume > All >Done.

4. Observe the model. Notice the pre-constructed solid stiffener thatis approximately created.

Figure 7: The Stiffener for the Upper Section


NOTES

Task 2. Copy and offset the top-most solid surface of the upper sectionto create a quilt. Use it to replace the stiffener surfaces.

1. Click Insert > Surface > Offset.

2. Select the top-most surface of the fuselage, as shown in thefollowing figure.

Figure 8

3. To specify the offset distance, in the Offset text box, type [1.0]

and click .

Figure 9: Offset Surface

Task 3. Replace the top surfaces of the stiffener with the offset surfacethat you have created.

1. To replace the first surface, click Insert > Advanced > ReplaceSurface.

2. Select the surface to replace shown as meshed in the followingfigure.


NOTES

Figure 10

3. Select the offset surface as the replacement surface.

4. To retain the quilt to replace the next surface, click Keep Quilt >Define > Yes > Done.

5. To complete the feature, click OK.

6. Observe the model. Note that the solid surface follows the fuselageshape by a 1-inch offset.

Figure 11

7. To replace the second surface, click Insert > Advanced >Replace Surface.

8. Select the surface shown as meshed in the following figure.

Figure 12


NOTES

9. Select the offset surface as the replacement surface.

10. You no longer need the offset surface feature, therefore, finish thesurface replacement. Click OK.

Task 4. Replace the stiffener bottom surface, which is underneath thefuselage with the copy of the inside surface of the upper section.

1. Click > View1.

2. To copy the surface, click Insert > Surface > Copy.

3. Select the surface shown as meshed in the following figure whileretaining the defaults Include and Indiv Surfs. Click Done Sel >Done > OK.

Figure 13

4. Click Insert > Advanced >Replace Surface.


Figure 14

6. Select the copied surface as the replacement surface and click OK.


NOTES

Figure 15

Task 5. Using Replace, match the stiffener front surface to the fuselagefront surface.


2. To copy the fuselage front surface, click Insert > Surface > Copy.


Figure 16

4. Retain the defaults Include and Indiv Surfs. Click Done Sel >Done > OK.

5. To replace the front surface of the stiffener, click Insert >Advanced > Replace Surface.



NOTES

Figure 17

7. Select the copied surface as the replacement quilt and click OK.

Figure 18

Task 6. Create surface replacements for the back vertical stiffenersurface the same way you created those for the front.

1. Change the view so you can view the back of the stiffener.

2. Create a copy of the width of the upper section. Follow the stepsmentioned in the previous task.

3. Replace the back surface of the stiffener with the new copysurface. Follow the steps mentioned in the previous task.

Figure 19: Final Result of the Replacement Operations


NOTES

Task 7. To create a rib between the upper and the lower section, firstcreate a rectangular block then replace its top and bottom surfaces with thecopy of the inner surfaces of the upper and lower section of the fuselage.

1. To create a copy of the inner surface of the upper section, clickInsert > Surface > Copy.


3. Click Done Sel > Done > OK.

Figure 20

4. Change the view to see the inner surface of the lower section.

5. To create a copy of the inner surface of the lower section, clickInsert > Surface > Copy.

Figure 21 Selecting Inner Surfaces

6. Click Done Sel > Done > OK.


NOTES

Task 8. Create the rib by building a solid protrusion in the middle of thetwo sections.

1. Click Insert > Protrusion > Extrude > One Side > Done.

2. Select the FRONT datum as the sketching plane. Accept thedefault direction and click Okay.

3. Click Right and select the RIGHT datum as the reference plane.

4. Sketch the section shown in the following figure.

Figure 22

5. To finish the sketch, click .

6. Retain Blind and click Done. Type [10] and click > OK.

Figure 23


NOTES

Task 9. To modify the upper and lower solid surfaces of the rib block,replace them with the copied quilts of the upper and the lower sections.

1. Click Insert > Advanced > Replace Surface.

2. Select the top flat surface of the rectangular solid.

3. Select the copied quilt of the upper section and click OK.

4. Repeat the steps for the bottom surface of the rib block. Use thecopied quilt of the lower section.

Figure 24

Task 10. (Optional) Remove the additional material from the rib block.Shell the block.

1. Click Insert > Shell.

2. Retain the default Add and select the solid surfaces shown asmeshed in the following figure. Click Done Sel and Done Refs.

Figure 25


NOTES

3. Type [0.5] and then click > OK.

Figure 26

4. Save and erase the part from memory.


NOTES

EXERCISE 2: Creating Cuts Using Surfaces

Task 1. Open the model and create a quilt to cut the pre-constructedsolid.

1. Open SURF_CUT.PRT.

Figure 27: Model at Start

2. Click Insert > Surface > Extrude. Retain One Side, Open Endsand click Done.

3. Select the side-wall as the sketching plane, as shown in thefollowing figure.

4. Choose the feature direction, as shown in the following figure,click Okay.

Select this surface asthe sketching plane

Select thissurface as theTop reference

plane

Feature direction

Figure 28


NOTES

5. Click Top and select the top surface, as shown in the precedingfigure.

6. Sketch the section, as shown in the following figure; the sketchconsists of two lines.

Figure 29: Section

7. Click to finish the sketch.

8. Click UpTo Surface > Done, then select the opposite side surface,as shown in the following figure.

9. Click OK to complete the feature creation.

Extrude up tothis surface

Figure 30

Task 2. Extrude a surface from the top surface of the solid in order todefine the profile of the cut. Extrude it up to the surface that is parallel tothe sketching plane.

1. Click Insert > Surface > Extrude. Retain One Side and OpenEnds, then click Done.


NOTES

2. Define the sketching plane and the feature direction, as shown inthe figure, then click Okay.

Select this surfaceas the referenceplane

Select this topsurface as the

sketchingplane

Featuredirection

Figure 31: Defining Feature Direction

3. Click Top and select the back face as the reference plane, as shownin the preceding figure.

4. Select two edges to specify additional references, as shown in thefollowing figure.

5. Sketch the section with the dimensioning scheme shown in the

following figure. Click to finish the sketch.

Select thesefor reference

Centerline

Figure 32: Dimensioning Scheme


NOTES

6. Click UpTo Surface > Done, then select the planar portion of thefirst surface that is parallel to the sketching plane.

7. Click OK to complete the surface creation.

Figure 33

Task 3. Create a single surface quilt by merging the two quilts that youjust created.

1. Click Insert > Surface Operation > Merge > Intersect.

2. Select the first quilt that you created then select the second.Pro/ENGINEER highlights the resulting. If necessary, click Side 1to retain the portions shown in the following figure.

Figure 34: Merging Two Quilts

3. To finish merging the surfaces, click .


NOTES

Task 4. Use the merged quilt to remove the material from the solid.

1. Click Insert Cut > Use Quilt.

2. Select the merged quilt. To select the area to be removed, in theCUT dialog box, click Side 2.

Figure 35

3. To complete the feature, click . The final part should look likethe one shown in the following figure.

Figure 36: Finished Part

4. Save and erase the part from memory.


NOTES


• You can create complex solid surfaces using quilts.

• You can use Surface Replace, Patch and Cut to accomplish this.

• Surface Replace allows you to replace a solid surface with a quilt.

• Patch allows you to replace a portion of a surface or multiple surfaceswith a single quilt.

• To create a patch feature, all the boundaries of the replacement quiltmust lie on the surfaces being patched.

• While using a quilt to cut a solid, the quilt must intersect the solid.

Page 6-1

Module

Creating Solids Using QuiltsIn this module you learn how to create solids from surfaces or quilts.

Objectives


• Create a thin feature using open quilts.

• Create a solid feature using closed quilts.

• Create a solid feature using open quilts that intersect with solids.

• Create offset features using different options.


NOTES

USING QUILTS TO GENERATE SOLID FEATURES

Creating a Thin FeatureYou provide thickness to a surface or a quilt using the Protrusion, Use Quilt,Thin option.

Figure 1: Creating Thin Features

The maximum thickness you provide to a quilt depends on the minimum radii ofthe side that you want to protrude. If you provide thickness greater than theminimum radius, the surfaces can self-intersect and the feature may fail. Toavoid this problem, Pro/ENGINEER offers different methods of offsetting whilecalculating the protrusion.

Protruding a Solid FeatureYou create a solid part from an enclosed surface or a quilt using the Protrusion,Use Quilt, Solid option.

Figure 2: Creating a Solid Protrusion from Enclosed Quilt

Creat ing Sol ids Using Qu i l ts Page 6-3

NOTES

Combining an Intersecting QuiltSurfaces or quilts that are not enclosed but intersect with a solid feature arealigned with the solid feature. You use them to create a solid part that is mergedwith the intersecting solid.

Extruded, mirroredand copied surfaceson base solid

Solid protrusion

Merge intersect

Figure 3: An Intersecting Quilt Feature

Solids Features on Surfaces

You can use solid feature options such as Draft and Rounds on surfacefeatures. You add drafts to surface geometry using the same method you use tocreate drafts in a solid part. You can also add round features to a surface modelthat automatically merge with the surface geometry.


NOTES

OFFSETTING SURFACESYou create a surface offset feature from a quilt or a solid surface. The offsetsurface remains linked to the reference surface.

Offset MethodsYou offset a surface using one of the following three options:

• Normal to Surface

• Auto Fit

• Controlled Fit

Using the Normal to Surface Option

The Normal to Surface option creates an offset feature that is normal to thereference surface. It is the default option.

This option is suitable when you create an offset feature that is less than orequal to the minimum radius of the reference surface. If you provide the offsetvalue that is greater than the minimum radius of the quilt, the feature would fail,since it would intersect with itself.

The following figure displays the result of offsetting a surface that hasminimum radius of 1.158.

Min Inside Radiusof the outsidesurface = 1.158

Collapsing pointat offset > 1.158

Offset = 1.15

Figure 4: Normal to the Base Surface


NOTES

Using the Auto Fit Option

The Auto Fit option offsets the surface by scaling the new surface to a system-defined coordinate system. The following figure displays the offset featureusing the Auto Fit option with an offset distance greater than the minimumradius.

Offset = 0.2

Figure 5: Using Auto Fit Option

Using the Controlled Fit Option

The Controlled Fit option offsets the surface by creating a best-fit offset that isscaled with respect to a selected coordinate system. It allows you to define theaxis for translation (X, Y, and/or Z).

The following figure displays an offset feature using the Controlled Fit optionwith the offset value of 0.2. In this example, the translation was allowed in allaxes.

Offset = 0.2

Figure 6: Using the Controlled Fit Option


NOTES

Using the Special Handlings Option

While offsetting the surfaces, the OFFSET dialog box to leave out the surfacesthat you do not want to offset, as shown in the following figure.

Figure 7: Using the Special Handlings Option

Using Offset Surfaces for Shelling

When you remove material from intricately shaped models using the solid Shelloption, undesirable results can occur, as shown in the following figure.

Figure 8: Removing Material Using Solid Shell Option


NOTES

The following steps illustrate using surfaces to remove material from the solidmodel.

Step 1 – Copy the surface and offset the copy.

Step 2 – Create an additional surface to join the two surfaces.

Step 3 – Copy the base and offset the surface.


NOTES

Step 4 – Merge the surfaces to create a single quilt.

Step 5 – Use the quilt to cut the solid.


NOTES


In this laboratory you create a solid thin feature from a quilt using different

offset options. You also remove material from a solid using a quilt.

Method

In the first exercise, you create a solid part from the quilt of a car hood. Youlearn to use different offset options in order to create thickness that is greaterthan the minimum radius of the quilt.

In the second exercise, you remove material from the cap of projector. You usean offset quilt to remove the material.


Saved View List

Build Feature

Preview Feature

View Repaint

Done


NOTES

EXERCISE 1: Creating a Solid Part of a Car Hood

Task 1. Create a thin protrusion.

1. Open CAR_HOOD.PRT.


2. To create a thin protrusion, click Insert > Thin Protrusion > Use Quilt.

3. Select the main quilt.

4. To define the direction, click Side 2 in the PROTRUSION dialog box.

5. To define the thickness, type [0.18]. Click to finish creating thefeature.

6. Observe the model and notice that the thickness is provided evenly andproperly around the model.

Task 2. Modify the thickness so it is greater than the minimum radius of aquilt.

1. Measure the minimum radius. Click Analysis > Surface Analysis. Inthe SURFACE ANALYSIS dialog box, select Radius from the TYPE list.

2. Select Surface from the DEFINITION list. In the housing, the minimumradius is most likely to be at the radius. Select the two fillet surfaces, asshown the following figure. Click Compute.


NOTES

Figure 10

3. Notice that the minimum inside radius is -0.1859.

4. Close the SURFACE ANALYSIS dialog box.

5. Modify the thickness of the part. In the PART menu, click Modify, thenselect the model. Change the part thickness to [0.25].

6. Click Regenerate.

7. Notice that the regeneration fails and the FAILURE DIAGNOSTICSdialog box displays the message “Could not construct feature geometry.”This is a result of the thickness of the model exceeding the minimumradius 0.1859.

Task 3. Fix the model by redefining the part leaving out the problem surfaces.

1. From the Menu Manager, click Quick Fix > Redefine > Confirm.

2. To access the DEFINE SPECIAL HANDLING dialog box, click Next.

3. Notice the highlighted fillet edges.

4. In the DEFINE SPECIAL HANDLING dialog box, click Yes. This willautomatically add four surfaces to the dialog box. Notice that thesurfaces highlight in the model as you drag over the list of surfaces inthe dialog box.

5. Click [Preview Feature], then click .

6. Click Yes to exit the Resolve mode.


NOTES

Task 4. Using pre-defined sections, view the protrusion around the failedfillets.

1. Notice the open round surfaces that are not protruded.

2. To view the pre-defined sections, click X-Section > Show > A, in thePART menu.

3. View the section and notice that the rounds portions did not protrude, asshown in the following figure.

4. When finished click Done/Return.

Figure 11: Section A Detail

Task 5. Make a protrusion that is greater than the minimum radius using theAuto Fit option.

1. To change the offset type, redefine the protrusion. Click Feature >Redefine and select the protrusion.

2. From the OFFSET TYPE area of the dialog box, click Auto Fit.

3. Finish the feature creation. Click OK to accept the warning message,

then click .

4. Study the model in Wireframe display mode. Notice that there are noopen surfaces.


NOTES

5. Display the predefined section again. Return to the PART menu. ClickDone, then click X-section > Show > A to view the section.

6. Notice that the thickness has been applied to all surface patches, but theprotrusion is not normal to the surface along the edges. ClickDone/Return.

Figure 12: Section A Detail

Task 6. Redefine the feature again and change the offset type to ControlledFit.

1. To redefine the protrusion. Click Feature > Redefine and select theprotrusion

2. To change the OFFSET TYPE, click Controlled Fit.

3. To define the offset options, click Next.

4. To define the coordinate system, select the CSO, as shown in thefollowing figure.


NOTES

Figure 13

5. To offset only in Z direction, clear the X-AXIS and Y-AXIS check boxes.

6. Click in the PROTRUSION dialog box to complete the feature.Click Done.

7. Display the SECTION A again.

8. Examine the SECTION A and the model. Rotate and zoom the model.Notice that the part is protruded normal to the surface around the edge,as shown in the following figure.

Figure 14: Part Protrudes Normal to Surface Around the Edge

9. Save the model and erase it out of the memory.


NOTES

EXERCISE 2: Using Offset Surfaces for Shelling

Task 1. Remove material from the cap.

1. Open CAP.PRT.

Remove bottom surface


2. To remove material, click Insert > Shell. Select the flat bottom surface,then click Done Sel > Done Refs.

3. Specify the thickness. Type [.33] and click .

4. To finish the feature creation, click OK.

5. Examine the model. Rotate and zoom the model and notice the shelledsolid around the round portion.

Figure 16


NOTES

6. To examine the predefined Section A, click X-Section > Show > A.Notice the undesirable section, as shown in the following figure.

Figure 17

7. In the CROSS SEC menu, click Done/Return.

Task 2. Create a quilt, then cut the solid with the quilt.

1. Delete the shell from the previous task. Select the shell feature from theModel Tree. Click Edit > Delete. Click OK in the warning window.

1. Copy the surfaces. Click Insert > Surface > Copy.

2. To copy the surfaces, click Surf & Bnd.

3. To specify the seed surface, select the meshed surface, as shown in thefollowing figure.

Figure 18


NOTES

4. To specify the boundary surface, select the meshed surface, as shown inthe following figure.

Figure 19

5. Click Done Sel > Done.

6. To confirm the selection, click Show > Mesh. Click beforecontinuing.

7. To exclude a surface from copying, click Exclude > Indiv Surfs fromthe SURF SELECT menu and select the round surfaces, as shown in thefollowing figure.

Exclude thesesurfaces

Figure 20

8. Finish the copy. Click Done Sel > Done > OK.

Task 3. Offset the surface created in the previous step.

1. Offset the surfaces. Click Insert > Surface > Offset, then select thecopied quilt

2. To define the direction, click SIDE 2.

3. Define the offset value and finish the feature creation. In the OFFSET

text box, type [0.33] and click .


NOTES

Task 4. Create a new surface and merge it with the existing surfaces.

1. Create a new surface. Click Insert > Surface > Revolve. Accept thedefaults and click Done.

2. Setup the sketching plane. Select FRONT and click Okay. To orient,click Top and select the TOP datum plane.

Sketch thesethree entities.

Figure 21

3. Add the existing surfaces as references. Sketch in the two lines, atangent arc and a centerline. Modify the radius of the arc to [0.25].

4. Finish defining the sketch. Click .

5. Specify the rotation. Click 360 > Done. Click OK to create the newrevolved surface.

Task 5. Merge the surfaces together and cut solid using the quilt.

1. Click Insert > Surface Operation > Merge > Join.

7. Select the quilts created in the previous task. (Select the larger surface).

To finish the operation, click .

8. Click Insert > Cut >Use Quilt.

9. Select the merged quilt. Accept the default as SIDE 1. Click .

10. Observe the Section A again.


NOTES

Figure 22



NOTES


• To create a solid part, you can add thickness to an open quilt or fill a closedquilt.

• By default, you add thickness to an open quilt that is less than its minimumradius.

• You use the Auto Fit and Controlled Fit offset options to provide thicknessthat is greater than the minimum radius.

• You also use quilts to remove material from a solid part in order to providethe desired shape to the inside/outside surfaces and thickness of a shell.

Page 7-1

Module

Boundary SurfacesIn this module, you learn to create different types of boundary

surfaces.

Objectives


• Create boundary surfaces using part edges and datum curves.

• Define tangency conditions of boundary surfaces.

• Define different types of boundary surfaces.


NOTES

CREATING SURFACES USING BOUNDARIESYou can create a surface by defining its boundaries. Boundaries can bedefined using part edges and other surfaces along with datum curves anddatum points. The following types of surfaces can be created:

• Blended

• Conic

• N-sided surfaces

BLENDED SURFACESTo create a blended surface, you use boundary curves to define the surfacein one or two directions. The system creates a blended surface between thereference entities. Therefore, the order that you select the boundary curvesis important.

Blending in a Single Direction

You can define surfaces from boundary curves using curves in onedirection only, as shown in the following figure.

Select thesecurves

Figure 1: Blended Surface Created from Curves in One Direction

Boundary Surfaces Page 7-3

NOTES

Blending in Two Directions

You can select entities in other directions to further control the shape ofthe surface, as shown in the following figure.

Select for firstdirection

Select forsecond direction

Figure 2: Blended Surface Created from Curves in Two Directions

Note:

For blended surfaces defined in two directions, the outerboundaries must form a closed loop.

Controlling the Boundary Conditions

You can control the boundary conditions of the blended surface using thefollowing options:

• Free

• Tangent

• Normal

• Curvature Continuous

ContinuousCurvature

Tangent

Free Normal

Figure 3: Boundary Conditions Shown with Porcupine Surface Analysis


NOTES

Blending the Control Points

When you create blended surfaces from boundary curves, Pro/ENGINEERmay create small patches that cause geometry check errors, undesirabletwisting, and stretching of the surfaces, as shown in the following figure.

Small patches thatcause geometry

check error

Figure 4: Small Patches Created from Surfaces by Boundaries

When you specify corresponding blend control points (either vertices ordatum points) on each of the curves/edges in the same direction, thesystem connects them point –by point and blends the correspondingportions (normalizing from 0 to 100 percent) between the points piece bypiece.

Boundary Influence

You can manipulate the boundaries of adjacent surfaces by defining theboundary influence.

Edges withboundaryinfluence

Figure 5: Boundary Influence


NOTES

Blended Surface with Approximate CurvesPro/ENGINEER allows you to create a blended surface feature usingcurve definitions that approximate the surface. You might generate thistype of curve using laser-scanning techniques, where machineinaccuracies or electronic noise can distort the data. Pro/ENGINEERaccepts as data the curves defining the boundary of the surface and anynumber of additional curves, in any direction that you want to use todefine it.

Figure 6: Blended Surface With and Without Approximate Curves

Note:

The restrictions that apply to blended surfaces in twodirections also apply to approximate surfaces in two directions.

You can define following two attributes while defining a blended surfaceusing curves in approximate directions:

• Smoothness

• Number of Patches


NOTES

Smoothness of an Approximate Blended Surface

The smoothness parameter specifies how many points of the given curvesthe system should use. The range of smoothness is 0 to 1, with 1 being thesmoothest (that is, it uses the fewest number of points).

Figure 7: Low and High Smoothness

Defining Number of Patches

The more patches you use, the closer the surface will fit the curve data.The fewer patches you use, the smoother the surface will be.

Figure 8: Less and More Patches


NOTES

CONIC SURFACESYou can create a conic surface by selecting two opposite boundary curvesand one control curve, which can be a shoulder or tangent curve.

ShoulderCurve

Figure 9: Conic Surface Using Shoulder Curve

TangentCurve

Figure 10: Conic Surface using Tangent Curve

Cross-section of a Conic Surface

Cross-sections of a conic surface can be hyperbola, parabola, or elliptical.It is controlled by the Conic Factor (rho).

Tangency of a Conic Surface

Pro/ENGINEER automatically defines the tangency conditions at the edgeof the conic surface based on the shoulder/tangent curve and the rho value.


NOTES

N-SIDED SURFACESYou can create blended surfaces from more than four bounding curves oredges using the N-Sided option, as shown in the following figure.

Figure 11: N-Sided Surfaces

RIBBON SURFACESThe Ribbon surface is a datum feature that is defined using a base curveand the reference curves. You can create a ribbon surface of a specifiedwidth along a base curve. The ribbon surface remains tangential to thereference curves.

Figure 12: Base Curve and Reference Curves

Ribbon surfaces are useful in following situations:

• When the reference curves are intersecting and do not allow you tomake boundary surfaces.


NOTES

• When the defining curves do not form a closed and do not allow you tomake boundary surfaces.

Figure 13: Ribbon Surface

Using Ribbon Surfaces

You can use a Ribbon surface to impose tangency conditions between twosurface features. With the Ribbon surface you can define the patchstructure so that adjacent surfaces can be made tangent to each otherwithout using one of them as a tangent reference.

Figure 14: Two Surfaces Tangential to a Ribbon Feature


NOTES


In this laboratory, you create blended surfaces using datum curves andedges. You also manipulate the boundary conditions and the blendcontrol points of blended surfaces.

Method

In the first exercise you create blended surfaces to join four cylindricalsurface features together. The blended surfaces are created usingtangential datum curves between the cylindrical surfaces. To join thesurfaces smoothly, you define the boundary conditions to be tangent.

In the second exercise, you create a blended surface then redefine thesurfaces to remove the small patches using the blend control points option.


Saved View List

Build Feature

View Repaint

Make selected layers Shown

Make selected layers Blanked

Build and repeat the feature

Insert Datum Curve

Insert Datum points

Quality

Show/Hide

Datum Points On/Off

Done


NOTES

EXERCISE 1: Blending Surfaces

Figure 15: Full model of the Tennis Racquet

Task 1. Open and examine the model.

1. Open TENNIS_RACQUET.PRT.

2. Examine the model. Notice the pre-constructed geometry.

Figure 16

3. For an uncluttered view, hide the datum planes and points display.

4. To have a closer look of the area you need to work on, click >View 1.


NOTES

Figure 17

5. Examine the model. Notice the intersection of the two tubes. Youare going to blend the tubes, as shown in the following figure.

Figure 18: Final Blended Surfaces

Task 2. To create a blend between the two tubes, the tubes are trimmedso that they are they are divided in three portions, A, B and C. Hide thetrimmed surfaces and the unwanted geometry.

1. Click View > Layers. In the LAYERS dialog box, select HANDLE,DATUM_PLANES and EXTRA_GEOMETRY. Click .

2. To show the names of the trimmed portions, select TUBES_NAME.

Click > > Close.

Figure 19


NOTES

Task 3. Create a curve, tangential to the tube A and B.

1. Click > Thru Points > Done. Retain the defaults, Spline,Whole Array and Add Point. Select the vertex as shown in thefollowing figure.

Figure 20

2. Select the second vertex shown in the following figure.

Figure 21

3. Click Done Sel > Done.

4. To define the tangency, click Tangency > Define.

5. To define the tangency of the start point, retain the defaults andselect the edge shown in the following figure. Click Okay.

Figure 22


NOTES

6. To define the tangency of the end point, retain the defaults andselect the edge shown in the following figure.

Figure 23

7. If necessary, using Flip, change the arrow direction, as shown inthe previous figure. Click Okay.

8. To finish curve creation, click Done Return > OK.

Figure 24

Task 4. Create points to create second curve.

1. Turn on the datum points display.

2. Click > On Curve > Length Ratio. Select the edge of thetube A, at the location shown in the following figure.


NOTES

Figure 25

3. Click Done Sel. Type [0.63] and click .

4. To create another point, click On Curve > Length Ratio. Selectthe edge of the tube B, at the location shown in the followingfigure.

Figure 26

5. Click Done Sel. Type [0.37] and click .

6. To finish creating points, click Done.

Figure 27


NOTES

Task 5. Cerate a curve tangential to the tube A and B.

1. Using the method outlined in the previous task, create a curvethrough the points, PNT21 and PNT22.

Figure 28

2. To define curve tangency, click Tangency > Define.

3. To define the tangency of the start point, click Srf Nrm Edge.Select the tube A, then select the edge shown in the followingfigure.

Figure 29


5. To define the tangency of the end point, click Srf Nrm Edge.Select the tube B, and then select the edge shown in the followingfigure.


NOTES

Figure 30


7. To finish defining the curve, click Done Return > OK.

Figure 31

Task 6. Create a boundary surface, tangential to the tubes A and B.

1. Click Insert > Surface > From Boundaries > Blended Surf >Done.

2. Select first direction curves shown in the following figure, andthen click Done Sel.

Figure 32


NOTES

3. To define second direction curves, click Second Dir.

4. Define the edge of the tube A as the first boundary in the seconddirection. Click Chain > Bndry Chain.

5. Select tube A then click From-To. Select the points shown in thefollowing figure. Click Next until the correct edge (on which PNT21 is lying) is highlighted, then click Accept.

Figure 33

6. To form a closed loop, trim the edge, in the Chain menu, clickTrim/Extend. Click Next until the point shown in the followingfigure is highlighted. Click Accept > Trim At > Point. Select thepoint PNT21, then click Done.

Figure 34

7. Define the edge of the tube B as the second boundary in the seconddirection. Using the method outlined in the previous step, firstselect the suitable boundary chain the tube B, and then trim theedge to form a closed loop.

8. Click Done > Done Curves.


NOTES

9. To define the boundary conditions, click Bndry Conds > Definefrom the SURFACE: BLENDED dialog box.

10. In the BOUNDARY dialog box, move the cursor over the boundarylist until the edge lying on tube A is highlighted. Click Boundary# > Tangent > Done > OK.

11. Using the same method, define the tangency of the boundary lyingon tube B.

12. To define the surface as normal to the TOP datum plane, move thecursor over the boundary list until the curve shown in thefollowing figure is highlighted. Click Boundary # > Normal >Done.

Figure 35

13. Select the TOP datum plane and click Done > OK.

14. To finish defining the boundary conditions and the surface, clickDone > OK.

Task 7. The next surface between the tubes A and C is created for you.It is kept hidden in a layer. Display the pre-constructed geometry.

1. Click View > Layers > Ready_Geometry > > > Close.

Figure 36


NOTES

Task 8. In order to create the next surface, create a curve that istangential to tube B and C.

1. Click > Thru Points > Done. Retain the defaults, Spline,Whole Array, and Add Point. Select PNT 22, then select PNT 20.Click Done.

Figure 37


3. To make curve tangential to the first boundary surface, click SrfNrm Edge. Select the meshed surface then select the edge shownin the following figure.

Figure 38


5. To define the tangency of the end point, click Srf Nrm Edge.Select the meshed surface then select the edge shown in thefollowing figure.


NOTES

Figure 39

6. Click Done Return > OK.

Task 9. Create a boundary surface, tangential to the two adjacentsurfaces and to the tube A.


2. Select first direction curves shown in the following figure, andthen click Done Sel.

Figure 40

3. To define second direction curves, click Second Dir.

4. Select the curve joining PNT 22 and PNT20 as the first boundaryin the second direction.

5. Define the edge lying on the tube A as the second boundary in thesecond direction. Click Chain > Bndry Chain.

6. Select tube A then click From-To. Select the points shown in thefollowing figure. Click Next until the correct edge is highlighted,then click Accept.


NOTES

Figure 41

7. Trim the edge using the method outlined in previous steps. Thetrimmed boundary should lie between points PNT17 and PNT21.

8. Click Done > Done Curves.

9. Using the method outlined in the previous steps, define theboundary conditions so that the surface is tangential to the adjacentboundary surfaces and the tube A.

10. Finish defining the boundary conditions and the surface.

Figure 42

Task 10. In order to make the last surface, create a curve joining thetubes B and C.

1. Click > Thru Points > Done. Retain the defaults, Spline,Whole Array, and Add Point. Select the vertices shown in thefollowing figure.


NOTES

Figure 43

2. Make the curve tangential to the tube B and C, using Srf NrmEdge option.

Figure 44

3. Finish defining the tangency. Do not exit the CURVE: THROUGHPOINTS dialog box.

Task 11. To create a good resulting surface, refine the curve shape usingthe Tweak option.

1. Change to the TOP view.

2. In the CURVE: THROUGH POINTS dialog box, click Tweak >Define.

3. In the MODIFY dialog box, click Diagnostics to expand the dialogbox.

4. From the list, select Curvature, then click .

5. In the Diagnostics area, click Settings button. In the text box, type[0.1] and click OK.

6. To increase the resolution quality, click Computation button.

Click and move the slider to the right. Click OK.


NOTES

Figure 45

7. Drag the internal points so that final shape of the curve is as shownin the following figure.

Figure 46

8. Click to close the MODIFY CURVE dialog box.

9. Click OK to finish creating the curve.

Task 12. To create the another boundary of the last surface, create acurve, project it on to the surface, and then trim the surface using theprojected curve.

1. Using the method outlined in the previous steps, create a curvethrough the points PNT 20 and PNT 22, as shown in the followingfigure.


NOTES

Figure 47

2. Make the curve tangential to the tube B and C, using Srf NrmEdge option.

Figure 48

3. Refine the curve shape using Tweak option. The final shape of thecurve is shown in the following figure.

Figure 49

4. Finish defining the curve.


NOTES

Task 13. Project the curve that you have just created, on to the lastsurface and then trim the surface using the projected curve.

1. Click > Projected > Done > Select >Done.

2. Select the curve shown in the following figure.

Figure 50

3. Select the meshed surface shown in the previous figure.

4. Click Along Dir > Done. Select the TOP datum plane. Using Flip,change the arrow direction as shown in the following figure. ClickOkay.

Figure 51

5. To finish defining the curve, click OK.

6. To trim the surface, click Insert > Surface Trim > Use Curves.

7. Select the meshed surface, and then select the projected curveshown in the following figure. Click Done.


NOTES

Figure 52

8. To define the side to keep, click Side 1 > Done > OK.

Figure 53

Task 14. Create the closing surface.


2. Select first direction curves shown in the following figure, clickDone Sel.

Figure 54


NOTES

3. Define the boundary edges of the tubes B and C as the seconddirection curves. Use the method already outlined to trim theedges.

Figure 55

4. Define the boundary conditions so that the surface is tangential toall the adjacent surfaces and normal to the TOP datum plane.

5. Finish creating the surface.

Figure 56



NOTES

EXERCISE 2: Changing Blend Control Points

Figure 57: The Complete Part

Task 1. Open the Planter model and observe the pre-constructed datathen blank the layer that contains it.

1. Open PLANTER.PRT.

Figure 58: The Start Model

2. Observe the pre-constructed surfaces of the top part of the planterand the curves to create the bottom part.

3. Blank the Surf layer. Click View > Layers > SURFACES > >

> Close.


NOTES

4. To change the view click > View1.

Task 2. Create a surface-by-boundaries using datum curves.

1. Create a blended surface. Click Insert > Surface > FromBoundaries > Blended Surf >Done.

Figure 59: First Direction Curves

2. To define the curves in the first direction, retain the defaults FirstDir, Add Item, and Curve. Select the curves shown in thepreceding figure. Click Done Sel.

3. To define the curves in the second direction, click Second Dir.Retain the defaults Add Item and Curve and select the two largercurves. Click Done Sel.

4. Finish defining the curves and preview the surface. Click DoneCurves then click Preview.

Figure 60: Previewing Curves


NOTES

Task 3. You will mirror the half model to create the other side of themodel. In order to achieve continuity with the mirrored half, make thesurfaces normal to the RIGHT datum plane.

1. Define boundary conditions for the surface. In SURFACE:BLENDED dialog box, click Bndry Conds > Define.

2. Select the first boundary. To identify the correct boundary, movethe mouse over the boundary list until one of the boundaries shownin the following figure is highlighted.

Figure 61

3. Change the boundary condition. Click Normal > Done > OK.

4. Select the second boundary. Move the mouse over the boundarylist until the next boundary is highlighted. Click Boundary #.

5. Change the boundary condition. Click Normal > Done > OK.

6. Finish defining the boundary conditions and complete the surfacefeature. Click Done > OK.

7. Observe the model in wireframe mode and notice narrow patchesbetween the tangent edges.

Task 4. Redefine the surface to use control points to remove unwantedsmall surface patches.

1. Select the surface you just create and right-click Redefine.

2. To add blend control points, click Control Points > Define.


NOTES

3. Set up control points in the first direction. Retain the defaults FirstDir and Add Set, then select the three vertices, one after another,in the order shown in the following figure.

Select this asfirst vertex

Select this asnext vertex

Select this aslast vertex

Figure 62: Selecting Vertices in the First Direction

4. Set up control points in the second direction. Click Second Dir.Select the vertex of the top curve, and then select second vertex ofthe bottom curve, as shown in the following figure.

First selectthis vertex

Then selectthis vertex

Figure 63: Selecting Vertices in the Second Direction

5. Continue selecting the next vertices on the top and bottom curves.(Do not select the red vertices at the ends of the surfaceyou mustselect four sets of control points).

6. Finish selecting the vertices. Click Done Sel > Done.

7. Finish creating the surface. Click OK.


NOTES

Figure 64: Finished Surface

Task 5. Create the other half of the model.

1. Click Insert > Surface Operation > Transform > Mirror > Copy>Done.

2. Select the surface, and then click Done Sel.

3. Specify the plane. Select the RIGHT datum plane.

Figure 65: Mirroring Created Surface

4. To merge the surfaces, click Insert > Surface Operation > Merge

> Join, then select the surfaces. Click .

Task 6. (Optional) Build the rest of the model by merging the pre-constructed top portion and adding the rounds.

1. Show the Surface layer. Click View > Layers > SURFACES >

> > Close.


NOTES

2. Merge the surfaces. Click Insert > Surface Operation > Merge >Join. Select the quilt that you have merged, then select the pre-constructed surface, as shown in the following figure.

3. Specify the portion of the quilt to retain. Click Side1 or Side 2 todisplay the model as shown in the following figure.

Figure 66: Retaining Certain Quilt Portions

4. Continue merging the surfaces. Click , then select the flatsurface. Click Side 1 or Side 2 to display the model as shown inthe following figure.

Figure 67: Merging Surfaces

5. Finish merging the surfaces. Click .

6. Create a simple round where the boundary’s surface meets theextruded surface. Click Insert >Round > Simple > Done.

7. Retain the defaults Constant and Edge Chain, then click Done.


NOTES

8. Select the edge. Retain the default Tangent Chain, select the edgeshown in the following figure. Click Done.

Figure 68

9. Type [0.5] as the radius value and click .

10. Finish creating the round. Click OK.

Figure 69

11. Create a round where the flat surface joins the side surfaces. ClickCreate > Solid > Round > Simple > Done.

12. Retain the defaults Constant and Edge Chain, and click Done.

13. Retain the default Tangent Chain, select the edge shown in thefollowing figure. Click Done.


NOTES

Figure 70

14. Type [0.75] as the radius value and click .

15. Finish creating the round. Click OK.

Figure 71



NOTES


• You can create Blended, Conic, and N-Sided surfaces usingboundaries.

• You can make boundary surfaces tangential to the adjacent surfaces byredefining the boundary conditions.

• You can make smooth, large surface patches by manipulating theblend control points.

Page 8-1

Module

Variable Section SweepIn this module, you learn to create variable section sweeps to capture

the design intent of complex shapes.

Objectives

After completing this module you will be able to:

• Define different types of trajectories in order to control the shapeof a variable section sweep.

• Manipulate the shape of a variable section sweep using variousoptions to orient the cross section.

• Define the tangent conditions to create a continuous variablesection sweep.

• Define limitations on a variable section sweep.


NOTES

THE VARIABLE SECTION SWEEPVariable section sweeps capture the design intent of complex shapes. Tocreate a variable section sweep feature, you sweep a single sketchedsection along one or more trajectories. The size and shape of the sectionvaries as the section moves along the sweep trajectories. You select thetrajectories from datum curves or sketch them during feature creation.

Defining Trajectories• Origin Trajectory – The one spine trajectory necessary in every

variable section sweep.

• X-Trajectory – Defines the section’s horizontal vector. In theSketcher, the origin of the section (indicated by the two centerlines) isalways located on the Origin Trajectory with the X-trajectory alwayslocated in the positive x direction.

• Other Trajectories – Defines other trajectories to control the shape ofthe surface feature.

Tips & Techniques:

You build flexibility into your model by selecting datumcurves to create the sweep trajectories instead of sketchingthem.

Specifying Section OrientationThe variable section sweep feature enables you to control how the systemsweeps the cross section to the origin trajectory. You define the feature byspecifying the orientation of the cross section with the following options:

Normal to Origin Trajectory

You sweep the section along the origin trajectory with a constant normaltrajectory. The origin trajectory curve defines a perpendicular for thesection as it sweeps along the trajectory.

Var iab le Sect ion Sweep Page 8-3

NOTES

Origin trajectory

Figure 1: Normal to Origin Trajectory

Normal to Trajectory

You sweep the cross section sweep normal to a selected curve other thanthe origin trajectory, as shown in the following figure.

Origin Trajectory

Other Trajectory

Figure 2: Normal to Selected Trajectory

Pivot Direction

You specify a reference (datum plane, curve, or axis) so that the crosssection remains normal to that reference, as shown in the following figure.If you select a curve that is not linear, then you select a datum point alongthe curve to make tangent and the system determines the perpendicular.

Normal toFront datumplane

Figure 3: Normal to Pivot Plane


NOTES

Creating a Normal to origin Trajectory Variable SectionSweep

When creating a normal to origin trajectory variable section sweep, youdefine at least one additional trajectory—the X-trajectory. The system usesthis trajectory to orient the section during the sweep. The section plane isalways normal to the origin trajectory at their intersection, as shown in thefollowing figure.

Resulting feature twists dueto change in horizontal

determined by x-trajectory

Origin trajectory

x-trajectory X-trajectory setsup horizontal forSketcher

Figure 4: Result of X-Vector

Using Additional Trajectories to Define the Shape

Once you have defined the origin trajectory and x-trajectory (whenneeded), you select or sketch additional trajectories to define the shape ofthe swept section, as shown in the following figure. Pro/ENGINEERautomatically add a Sketcher point at the intersection of any additionaltrajectory and the sketching plane of the section. As the system sweeps thesection plane along the trajectories, its intersection with the curves(trajectories) represents known points for section dimension andalignment. When you dimension or align section vertices to the x-trajectory and additional trajectories, these curves represent the trajectoryof the section vertex.


NOTES

Origin trajectory using pivotdirection option

Additionaltrajectories

Figure 5: Using Multiple Trajectories

Defining Tangent Geometry

You select a tangent trajectory to define a tangent centerline in the sectionthat you sketch for the variable section sweep. If you reference thiscenterline for tangency, the section remains tangent at all points along thesweep.

Tangentcenterlines

Note transition tosurface is smooth

Figure 6: Using a Tangent Trajectory

Adding Control: Using Relations in VariableSection SweepsWhen the system regenerates a variable section sweep, it automaticallyevaluates an internal parameter called a trajpar (trajectory parameter). Thisparameter has a normalized value between 0 and 1, representing thepercentage length of the swept feature. The value of trajpar is 0 at thebeginning and 1 at the end. You utilize this value by adding relations tocontrol the section.


NOTES

Sketcherdimension

No relations

Added relationsd4 = trajpar + 1

Added relationSd4 = sin (trajpar *360) + 1.5

Figure 7: Using Trajpar to Drive the Section

Note:

The system only evaluates trajpar when it regenerates thefeature. You can only use this parameter in a feature relation.

The trajpar parameter is one of the most powerful functions of the variablesection sweep, as shown in the following figure. You can drive thesurfaces to 0 anywhere along the trajectory by using complex relations todrive the section or by evaluating a datum graph feature, known as anevalgraph.

Figure 8: Driving a Surface to Zero


NOTES

Restrictions on Variable Section SweepsA variable section sweep cannot be the first feature in a model, so you usethe default datum planes first. When you create a variable section sweep:

• The origin trajectory curve must consist of only tangent entities.

• The x-trajectory cannot cross the origin trajectory. However, eitherend point can intersect the origin trajectory.

• All additional trajectories intersect the sweep’s sketching plane, but donot have to be the same length as the origin trajectory. The systemmakes the sweep feature as long as the shortest trajectory (origintrajectory, x-vector, or optional trajectory).

• The sweep feature’s sketching plane can intersect any trajectory onlyonce at any given location along the sweep.

• If the sweep feature’s sketching plane cannot intersect all trajectoriesat the sweep’s start point, you can use a datum point (on the origintrajectory) to define the start point.


NOTES


In this laboratory you create surface features using variable section

sweeps. You also control the shape of the swept surface using graph and

trajectory parameters.

Method

In the first exercise, you create the middle portion of a plastic bottle. Tobuild the complex shape of the bottle, you use variable section sweep withdifferent options. You also modify the shape of the bottle using a graph.

In the second exercise, you create a compression washer using variablesection sweep option. You use the trajectory parameter to create asinusoidal shape of the washer.


Insert Datum Curve

Done


NOTES

EXERCISE 1: Using Variable Section Sweeps toDesign the Plastic Bottle

Figure 9: Model Start to Finish

Task 1. Open a model and review the pre-constructed geometry.

Figure 10: Reviewing Geometry

1. Open BOTTLE_MID_PORTION.PRT and review the pre-constructed geometry. The model contains the initial curves todefine the trajectories for the sweep.

2. Examine the current features of the bottle part. Click Info >Feature List, or use the Model Tree.


NOTES

3. Note the datum graph feature named CONIC. You use this later tocontrol a variable section sweep.

4. When you have finished reviewing the model, close all informationwindows.

Task 2. Construct the front side of the bottle using a variable sectionsweep.

1. Turn off the datum plane display to see the curves properly.

2. Create a variable section sweep surface. Click Insert > Surface >Variable Section Sweep > NrmToOriginTraj > Done.

3. To specify the origin trajectory, click Select Traj. Retain thedefaults One By One and Select. Select the straight datum curve,then click Done Sel.

4. Confirm that the start point of the sweep is at the bottom, as shownin the following figure. If necessary, change the location of thestart point using the Start Point option.

Figure 11

5. Click Done to finish defining the origin trajectory.

Task 3. Specify the x-trajectory to orient the cross section.

1. Click Select Traj > Curve Chain.

2. Select the left datum curve, ID 12, then click Select All.

3. Click Done to finish defining the x-trajectory.


NOTES

Task 4. Add an additional trajectory to further control the shape of thefeature and then finish defining the trajectories.

1. Specify an additional trajectory. Click Select Traj > Curve Chain.Select the right datum curve, then click Select All.

2. To finish defining the trajectories, click Done > Done.

3. Retain Open Ends and click Done.

Task 5. Create the cross section of the sweep

1. Accept the default Sketcher references and sketch the crosssection, as shown in the following figure. Use only one arc withone dimension.

Figure 12

2. Click > OK to finish the sketch and the feature creation.



NOTES

Figure 13

Task 6. Mirror the surface to create the back portion of the bottle.

1. Click Insert > Surface Operation > Transform > Mirror > Copy> Done.

2. Select the quilt that you just created, click Done Sel.

3. To specify the mirror plane, select FRONT.

Figure 14: Front and Back of Bottle

Task 7. To create the left side of the bottle as a boundary surface, builddatum curves.

1. Create a datum curve using the top two vertices of the two surfaces

that you have created. Click > Thru Points > Done. Retain thedefaults Spline, Whole Array, and Add Point.


NOTES

2. Select the top vertices of the two surfaces, as shown in thefollowing figure, then click Done.

Figure 15: Selecting Top Vertices

3. To define the tangency, click Tangency > Define in the CURVE:THROUGH POINTS dialog box.

4. To define the start tangency, retain the defaults Start,Crv/Edge/Axis, and Tangent, then select the edge shown in thefollowing figure.

Figure 16: Direction of Tangency

5. Using Flip, specify the correct tangency direction, as shown in theprevious figure, then click Okay.

6. Define tangency for the endpoint. Retain the defaults End,Crv/Edge/Axis, and Tangent, then select the edge shown in thefollowing figure.


NOTES

Figure 17: Direction of Tangency

4. Using Flip, specify the correct tangency direction, as shown in thepreceding figure, then click Okay.

5. Click Done/Return to finish defining the tangency.

6. Click OK to finish defining the curve.

7. Change the view so you see the bottom vertices, as shown in thefollowing figure.

Figure 18

8. Using the procedure outlined in the previous steps, create anotherdatum curve through the vertices shown in the preceding figure.

9. Define the tangency using the procedure outlined in the previoussteps. The final curves should display as shown in the followingfigure.


NOTES

Figure 19

Tips & Techniques:

If you specified the direction incorrectly, or, you cannotremember which one was the start point, you can redefine thetangency by clicking Start or End, selecting thecorresponding edge once more, and clicking Flip and OK.

Task 8. Create a surface by boundaries. Make it tangential to theadjacent surfaces.

1. Click Insert > Surface > From Boundaries > Blended Surf >Done to create a blended surface by boundaries.

2. Specify the curves in the first direction. Retain the defaults FirstDir, Add Item, and Curve, then select the two datum curves.

3. Define the first curve of the second direction. Click Second Dirand retain the default Add Item, then click Chain > TangentChain > Select. Select the edge of one of the surface, then clickDone.

Tips & Technique:

It is always good practice to use the edge of the adjacentsurface instead of that surface’s defining curves.


NOTES

4. Select the second surface edge as the second curve of the seconddirection. Click Tangent Chain, then select the edge of the othersurface, then click Done.

5. Click Done Curves to finish defining the boundary curves.

Figure 20

6. To define the boundary conditions, in the SURFACE: BLENDEDdialog box, click Bndry Conds > Define.

7. Identify the first correct boundary. Move the mouse cursor over theboundary list and note each of the boundaries as the screenhighlights them.

8. Select the boundary that highlights one of the larger edges of thevariable section sweep surface, BOUNDARY #3.

9. Change the boundary condition. Click Tangent > Done > OK.

10. Identify the second correct boundary. Select the boundary thathighlights the other larger edge of the variable section sweepsurface (BOUNDARY #4).

11. Change the boundary condition. Click Tangent > Done > OK.

12. To finish defining the boundary condition and the surface, clickDone > OK.


NOTES

Figure 21

Task 9. Build the right side of the bottle by creating a variable sectionsweep using a conic to allow for tangent geometry conditions.

1. Create a variable section swept surface using the pivot directionoption to orient the section. Click Insert > Surface > VariableSection Sweep > Pivot Dir > Done.

Note:

The pivot direction variable section sweep requires a referenceso that the cross section remains normal to that reference.

2. Specify the pivot direction reference. Retain the default Plane.Select RIGHT as the pivot direction plane and click Okay to acceptthe default direction.

3. Specify the origin trajectory using tangency. Click Sel Tan Traj >Tangnt Chain. Select one of the two edge chains as the origintrajectory, as shown in the following figure.


NOTES

Figure 22

4. Specify the start of the trajectory. Confirm that the start point ofthe sweep is at the bottom, as shown in the following figure. Ifnecessary, click Start Point > Next to change the location, thenclick Accept.

Figure 23

5. Click Done to finish defining the origin trajectory.

6. To define highlighted surface as tangent, click Accept.

7. Click Join > Done to merge the new surface with the existingsurface.


NOTES

Task 10. Specify the additional trajectory and the cross section.

1. Specify an additional tangent trajectory. Click Sel Tan Traj >Tangnt Chain. Select the other edge chain and click Done.

2. Specify the surface for tangency. Click Accept.

3. Click Join > Done to merge the new surface with the existing one.

4. Click Done to finish selecting the trajectories.

5. Retain Open Ends. Click Done to specify the attributes.

6. Create the cross section. Accept the default Sketcher referencesand sketch the section as a Conic.

7. Change the angular dimensions to 180 and type [0.35] as the RHOvalue.

Figure 24: Specifying the Right Side of the Bottle


9. Click OK from the dialog box to finish the surface creation.


NOTES

Figure 25

Task 11. Redefine the surface that you just created in order to control theshape of the cross section using the trajpar parameter and a graph.

1. Select the surface that you just created and right-click Redefine.

2. To add relation in the conic parameter, click Section > Define >Sketch in the SURFACE: VARIABLE SECTION SWEEP dialogbox.

Figure 26: Predefined Conic Graph

3. To drive the RHO value from the graph, click Sketch > Relations> Add.

4. Note that the sketch now shows the symbolic dimensioninformation. Type the relation [sd# = evalgraph (“CONIC”,trajpar * 10) / 10], where SD# is the symbol for the RHOdimension


NOTES

5. Click > to finish entering the relation.

6. To finish the sketch and the feature, Click > OK.

7. Notice the change in the shape of the surface after specifying therelation.

Figure 27



NOTES

EXERCISE 2: Creating a Wavy Washer

Figure 28: Finished Wavy Washer

Task 1. Create a new part and a datum curve to use it as the trajectoryfor a variable section sweep.

1. Create a new part named WAVY_WASHER.

2. To create a datum curve, click > Sketch > Done.

3. Specify the sketching plane. Select TOP, then click Okay to acceptthe default viewing direction.

4. Click Bottom, then select FRONT as the reference plane.

5. Accept the default Sketcher references and close the REFERENCESdialog box.

6. Sketch the circular datum curve, as shown in the following figure.Define the diameter as 1.00.


NOTES

Figure 29

7. Click > OK to finish the sketch and the feature creation.

Task 2. Create a sinusoidal surface using a variable section sweep andtrajpar in a relation.

1. Click Insert > Surface > Variable Section Sweep > Pivot Dir >Done.

2. Specify the pivot direction reference plane. Retain the defaultplane. Select TOP as the pivot direction plane. Click Okay toaccept the default direction.

3. Specify the origin trajectory. Click Select Traj > Curve Chain.Select the circular datum curve. Click Select All.

4. Click Done > Done to finish defining the origin trajectory.

5. Create the cross section. Accept the default Sketcher referencesand sketch a single straight line. Use the dimension scheme shownin the following figure.

Tips & Techniques:

You do not need to specify the vertical dimension because youuse it in a relation.


NOTES

Figure 30

6. To add a relation click Sketch > Relation > Add. Type therelation [sd# = sin(trajpar*360*6)/20], where SD# is thevertical dimension.

7. Click > to finish entering the relation.

8. Click to complete the sketch.

9. Click OK to complete the feature.



NOTES


• The variable section sweeps allow you to create complex geometrywith tight control.

• You control the shape of a section using a graph.

• You control the shape of the resultant geometry using a trajectoryparameter known as trajpar.

Page 9-1

Module

Swept BlendsIn this module you learn to create surfaces using the Swept Blend

tool.

Objectives


• Create surfaces using the Swept Blend tool.

• Manipulate the shape of swept blend surfaces using differenttechniques.

• Define and control the relation between sections and the trajectory.

• Define limitations on the swept blend surfaces.


NOTES

INTRODUCTIONTo create a swept blend feature, you blend several cross sections along asingle trajectory spine called the origin trajectory, as shown in thefollowing figure. Pro/ENGINEER automatically creates a smoothtransitional surface between the cross sections in the model. The shapes ofthe trajectory, as well as the selected sections, define the shape of thesurface.

Cross-sections

Origin Trajectory

Figure 1: Swept Blend

Defining the Origin TrajectoryThe origin trajectory can be an open or closed loop. To define a trajectory,you can sketch it, select a datum curve (or a part edge), or import curvegeometry.

Creating SectionsAfter defining the origin trajectory, you define the cross sections byselecting them or sketching them at specified segment vertices or datumpoints located on the curve. Pro/ENGINEER automatically generates acoordinate system at each sketching location so that you can rotate eachcross section about the Z-axis.

Orienting the Sections

Both the swept blend and variable section sweep feature enables you tocontrol how the system sweeps the cross section with the origin trajectory.You specify the orientation of the cross section in the following ways:

Swept B lends Page 9-3

NOTES

• Normal to the Origin Trajectory – Sweeps the section or sectionsalong the origin trajectory normal to the trajectory at all times. Theorigin trajectory curve defines a perpendicular for the section, as itsweeps along the trajectory, as shown in the following figure.

Trajectory

Figure 2: Normal to the Origin Trajectory

• Normal to Trajectory – Sweeps the cross section normal to a selectedtrajectory other than the origin trajectory, as shown in the followingfigure.

Origin trajectory

Othertrajectory

Figure 3: Normal to Selected Trajectory

• Pivot Direction – Establishes a reference (datum plane, curve, or axis)so that the cross section remains normal to the curve, as shown in thefollowing figure. If you select a curve that is not linear, you mustselect a datum point along that curve to make tangent, from whichPro/ENGINEER determines a perpendicular.

Normal to theFRONT plane

Figure 4: Normal to Pivot Plane


NOTES

Additional Controls to Modify the Swept BlendFeatureDefining Tangency

You specify tangent conditions to the end sections of a swept blendsurface.

Swept blendsurface tangent tothe adjacentsurface

Swept blendsurface

High dihedralshowing lackof tangency

Figure 5

Controlling the Shape between the Sections: Blend Control

The Blend Control feature enables you select a method for controlling theshape of the swept blend between its sections with the following options:

• Set Perimeter – Controls the shape of the feature by controlling itsperimeter between the sections. If two consecutive sections have equalperimeters, the system attempts to maintain the same cross sectionperimeter between these sections. For sections that have differentperimeters, the system uses smooth interpolation along each curve ofthe trajectory to define the perimeter of the feature between itssections.

� Center Crv – Shows a curve connecting the centroids of thecross sections. This option is available only with the SetPerimeter option.

Curveconnectingthe centroids

Figure 6: Using the Center Crv Option


NOTES

Note:

You cannot specify both perimeter control and tangencyconditions for the swept blend. Only one of these conditions isallowed.

• Area Graph – Controls the cross sectional area of the swept blendfeature at any point along the trajectory—without adding moresections.

Figure 7: Modifying the Shape Using Graph Feature


NOTES

Restrictions on Swept BlendsTo create a swept blend, all sections must intersect the trajectory with thefollowing restrictions:

• To create a closed trajectory, you use two sections: one sketched at thestart point and the other sketched at any other location.

• To create an open trajectory, you use a section at the start points andendpoints.

• You cannot select composite datum curves to define sections of aswept blend. Instead, you use the underlying curve segments or edgesfrom the composite curve.


NOTES


In this laboratory you create a swept blend surface feature and modify

the shape using a graph.

Method

In this exercise you create a MANIFOLD part using pre-constructedtrajectory and a rectangle section. To create the swept blend surface, youdefine the other section as a circle, locate the points where you want tochange the section area, then modify the area using a graph.


Saved View List

Insert Datum Curve

Select Geometry

Insert a Feature

Select Primary Items

Build Feature

Done


NOTES

EXERCISE 1: Creating a Manifold

Task 1. Open MANIFOLD.PRT and review its pre-constructedgeometry.

1. Observe the model. Notice the curve lying on the TOP datum planethat defines the trajectory. Also, notice the four datum curves thatdefine the first rectangular cross section of the swept surface.

Trajectory

Datum curves todefine the firstsection

Figure 8

Task 2. To create the swept blend surface, create the second crosssection by sketching a circle. Since the first section (rectangle) iscomposed of four entities, break up the circle into four entities.

1. Click Insert > Datum > Curve > Sketch > Done to create thesecond cross section at the other end of the trajectory curve.

2. To specify the sketching plane, select the RIGHT datum plane.


4. Click Top, then select TOP as the reference plane.

5. Accept the default references and close the dialog box.

6. Sketch the curve, as shown in the following figure. Use thecenterlines to intersect and break the circle into a four-arc segment.


NOTES

Figure 9

7. Click > OK to finish the sketch and the curve creation

Task 3. Construct the manifold surface using a normal to origintrajectory.

1. Click Insert > Surface > Swept Blend. In BLENDS OPTS menu,click Select Sec > NrmToOriginTraj > Done.

2. Specify the origin trajectory. Click Select Traj > Curve Chain.Select the trajectory shown in the following figure, then clickSelect All.

3. Confirm that the start point is at the end close to the rectanglesection, as shown in the following figure. Otherwise, change thelocation of the start point. Click Done.

Select thiscurve astrajectory

Start point

Figure 10


NOTES

4. To specify the attributes, click Open Ends > Done.

5. To specify the first cross section, retain the default Pick Curve andclick Sel Loop. Select the rectangular datum curve as the firstsection. Click Done Sel > Done/Return.

6. Note the location of the start point.

7. Click Done to finish defining the first cross section.

8. Specify the circular curve for the second cross section. Retain PickCurve as the default. Click Sel Loop.

9. Select the circular datum curve as the second section, then clickDone Sel > Done/Return.

10. To avoid twisting, if necessary, change the start point. Click StartPoint, then select the correct vertex on the circular cross section.Click Done.

11. Finish creating the swept blend. When the system prompts you tospecify another section, click NO, then click OK from the dialogbox.

Figure 11

Task 4. Create a flat surface to start the definition of the mountingflange for the manifold

1. Click Insert > Surface > Flat > Done to create a flat surface.

2. To specify the sketching plane, click Make Datum > Through,then select one of the long edges at the rectangular start of theswept blend.


NOTES

3. Click Through again. Select the other long edge at the rectangularstart cross section, then click Done.

4. Click OK to accept the default viewing direction.

5. To specify the reference plane, click Right, then select the RIGHTdatum plane.

6. Define the Sketcher references, then close the REFRENCES dialogbox.

7. To change the view, click > Default.

8. Define the section using the rectangular section. Click Sketch >Edge > Offset > Loop. Select the rectangular section.

9. To specify the offset distance. Type [-0.40], then click Close.

10. Click > OK to finish the sketch and the surface creation.

Figure 12

Task 5. Merge the flat surface to the swept blend surface to create anopening in the manifold.

1. Click Insert > Surface Operation > Merge > Intersect. Selectthe swept blend surface, then select the flat surface.

2. From the dialog box, select SIDE 2 for the additional quilt. Themodel should display as shown in the following figure.


NOTES

Figure 13

3. Finish merging the surfaces. Click .

Task 6. Add simple edge rounds along the four edges of the swept blendwith a radius of 0.5.

1. Click . Press and hold <SHIFT> and select the four edges shownin the following figure.

2. Right-click and select ROUND EDGES.

Select these four edges

Figure 14

3. Double-click the radius dimension and type [0.5] as the radiusvalue.

4. Regenerate the model.


NOTES

Figure 15

Task 7. To control the cross section using an area graph, create datumpoints on the trajectory. Insert the datum points before the swept blendfeature.

1. In the MODEL TREE, drag [Inset Here] between PNT0 and A_1to create the new datum point.

2. Create the datum points along the curve. Click Insert > Datum >Point > On Curve > Length Ratio.

3. Select the two locations for the points, as shown in the followingfigure. Confirm that the entire curve highlights for each point, notjust a single curve segment, then click Done Sel.

4. Specify the dimensions as percentages. Type [0.35] for the firstpoint. Type [0.75] for the second point.

5. Click Done to finish creating points.

Figure 16: Additional Datum Points


NOTES

6. To resume all suppressed features, drag [Insert Here] to thebottom of the Model Tree.

Task 8. Use area graph to control the shape of the cross section at thelocation where you have created the points. Redefine the swept blendfeature.

1. Click and select the swept blend from the model. Click Edit >Definition.

2. Define the blend control. Click Blend Control > Define > AreaGraph > Done/Return. The system will open a second windowdisplaying the existing area of the current model.

Tips & Techniques:

You can also use Set Perimeter to vary the perimeter of thecross sections.

Figure 17: Existing Area Graph of the Swept Blend

3. Add the first datum point to the graph. Retain the defaults Define,Add Point, and Select Point. Select the datum point PNT1 closestto the rectangular end.

4. Define the new area value. Type [3.00] and click . Observe thechange in the graph.

5. Modify area at the second point. Select the datum point PNT2

closest to the circular end. Type [2.25] and click .


NOTES

6. Click Done Sel > Done/Return > Done/Return > Done > OK tofinish the changes to the area graph and the complete the featurecreation.

Figure 18: Changes Resulting from Different Area Graph

Task 9. Modify the area graph dimension again.

1. Click Modify and select the swept blend. Click All.

2. Modify the dimensions 3.00 to 5.00 and 2.25 to 3.00, asshown in the following figure.

Figure 19

3. Regenerate the model and observe the change.


NOTES

Figure 20: Modified Manifold



NOTES


• A swept blend is defined by sweeping many sections (at least two),over a trajectory.

• To create a swept blend feature, you must have the same number ofentities in each section.

• You manipulate the area of a specified cross section using a graph,without having to introduce a specific section.

Page 10-1

Module

Surface Information & AnalysisIn this module, you learn how to use surface analysis tools.

Objectives


• Define the need to analyze surfaces.

• Analyze surfaces using different tools.


NOTES

ANALYZING GEOMETRYObtaining information on surface geometry during the design processhelps you to analyze:

• Surface quality of imported surfaces.

• Surface continuities.

• Reasons for failure of some surface operations.

• Aesthetic qualities of a design.

The wireframe and shaded model may not provide accurate informationabout the surfaces. Pro/ENGINEER offers a number of tools to analyzeand obtain the information about the model geometry.

Fringe Plot Analysis

For some types of analysis, you use fringe plots on the model to shadeselected surfaces in colors to represent values in a color range.

Fringe Plot Colors – Hot colors of the spectrum represent large positivevalues, whereas the cool colors, such as blue, represent highly negativevalues.

Using fringe plot analysis, you can extract information and analyze asurface by using any of the following tools:

• Gaussian Curvature

• Section Curvature

• Slope

• Draft Angle

Other Surface Analysis Tools

The following tools are not as graphics-intensive as the fringe plot; theyprovide plots or numerical results:

• Porcupine

• Normals

• Deviation

• Reflection Curves

• Radius

• Offset Mesh

• Highlight Curves

• Information at a Point

• Dihedral Angle

Surface Info rm at ion and Ana lys is Page 10-3

NOTES

Gaussian CurvaturePro/ENGINEER determines the Gaussian curvature as the product of thesmallest and largest normal curvature for every point on the surface. Thisproduces positive values (ridges), negative values (saddles), and zerovalues (e.g., cylinders and planes). You use the Gaussian curvature tool to:

• Display surface curvature in order to validate the design intent.

• Check surface continuities.

• Detect unwanted high curvature areas in a surface that can presentproblems in manufacturing.

Point ofmaximumcurvature

Point ofminimumcurvature

Figure 1: The Gaussian Curvature Tool

Using Gaussian Curvature to Check Surface Continuity

You detect discontinuities in the surface based on the discontinuities thatappear in the fringe plot.

Discontinuity inpattern

Figure 2: Discontinuity Shown by Gaussian Curvature


NOTES

Section CurvatureWhen you perform section curvature analysis, Pro/ENGINEER creates thecurvature fringe plot of cross-section cuts parallel to a reference plane.When you select a datum plane or planar surface, the system calculates thesurface curvature parallel to the selected plane.

Gaussian curvature analysis depicts the distortion of a surface in twodirections. Section curvature analysis enables you to examine specificareas in one direction at a time.

Surface selectedfor analysis

Front surface��

Figure 3: Section Curvature Analysis

Figure 4: Section Curvature Using Front Reference

Figure 5: Section Curvature Using Side Reference


NOTES

SlopeYou use the slope analysis tool to visualize the way a surface slopes awayfrom a selected plane. The system renders the slope of a surface relative to�� ranging from –1 to +1. For example, a 45-degree angle to a referenceplane results in a 0.707 slope.

Has zero Slope(normal to

selected plane)

Selected referenceand direction

Selectedreference

(No slope)

Zero slope

Figure 6: Using Slope Analysis

PorcupineUsing the Porcupine option, you graphically display the normal curvatureof a surface using isolines (equally spaced lines that display the contour ofthe surface in one direction) and line segments normal to the isolines. Thenormal line segments are equally spaced along the isolines, and theirlength is proportional to the surface’s normal curvature in the isoline’sdirection at that point. You display the isolines on the surface in either orboth of the two directions. The porcupine is an effective tool for analyzingdiscontinuities in surface curvature.

Porcupine displayingdiscontinuity in curvaturebetween two arc surfaces

Porcupine displayingcontinuity

Figure 7


NOTES

NormalsUsing the Normals option in the pull-down menu, you display vectorsnormal to a selected surface in green.

Figure 8: Surface Normals

Draft CheckUsing the draft check tool, you check the draft angle on the surfaces of thesolid model by setting up a plane to define the direction of pull for themold. This enables you to identify possible areas that could becomeproblematic when the part is pulled from a mold during manufacturing

Reflection CurvesUsing the Reflection Curves option, you simulate the reflection of lightfrom a linear source on a surface when viewed from a particular direction.You show the reflecting curves that pass through selected points within aspecified range of visibility, or within the entire range of visibility from aselected viewing direction.

Axis of lightsource

Plane of lightsources

Plane settingview direction

Discontinuity inthe reflection

Figure 9: Reflection Curves


NOTES

RadiusUsing the Radius option, you determine the minimum and maximumradius of a surface.

Point of outsideminimum radius

Figure 10: Determining the Minimum Radius

Offset MeshUsing the Offset Mesh option, you create a mesh offset from a selectedsurface, which is useful for exaggerating slight changes to check thequality of the surface. Visible cusps in the offset mesh show a radius ofcurvature smaller than the offset distance. This tool is useful forinterrogating geometry that fails when creating thin protrusions or shells.

Figure 11: Creating an Offset Mesh


NOTES

DeviationUsing the Deviation option, you analyze the deviation between differententities and the model surface using surface normals. This tool providesthe maximum and minimum distance between the selected references. Youcan enter a tolerance value to identify where the surface is out of toleranceto the selected entity. You select datum curves, datum points (a single oneor point array) and scan curves. This tool can be helpful when you areusing imported data to create geometry, such as imported curves or points.

Highlight CurvesUsing the Highlight Curves option, you create curves on a surface withcertain values of slope to a selected planar reference. You select pointsmanually on the surface or enter incremental degree values.

If you select the points manually, the system creates curves through thesurface at locations with the same slope as the selected point. If you enterangular increments, it creates highlight lines for each angular increment.This tool is useful for illustrating how a surface is contoured.

Selected reference using5-degree increments

Figure 12: Using Highlight Curves Tool

Information at a Certain PointUsing the Info at Point option, you extract information that provides thecoordinates, the unit normal and the unit direction vectors in a coordinatesystem; the signed principal curvatures at a point on a surface; theprincipal radii of curvature; and the product of the curvatures. Thisinformation can be useful when the design requires you to know exactinformation at a specified point. You can save the analysis for future use.


NOTES

Dihedral AngleThe Dihedral Angle option measures the angles between the tangents ofthe adjoining surfaces along the common edge. This tool is useful fordetermining if two surfaces are tangent (G1) or not, or the extent to whichthey are not tangent.

Selectededge

Point ofmaximumdihedral angle

Point of minimumdihedral angle

Figure 13


NOTES


In this laboratory, you learn how to use the most common surface and

curve analysis tools.

Method

In this exercise, you apply different analysis tools on two non-tangentialgeneric surfaces. You save the analysis, modify the surface properties, andthen study the changes in the analysis.


Saved View List

Show/Blank selected analysis

Preview feature geometry

Cancel feature creation

Quality

Number of points


NOTES

EXERCISE 1: Analyzing Surfaces

Task 1. Retrieve the model and review the two surfaces, A and B.

1. Open TWO_SURFACES.PRT.

Figure 14: Start Model

2. Review the model surfaces. Notice that the surface A has variedcurvatures in both positive and negative directions. Surface B hasless varying curvatures only in one direction. Also notice that thetwo surfaces are not continuous.

Task 2. Mesh the surfaces and review the geometry.

1. Click View > Model Setup >Mesh Surface, then select the twosurfaces.

Figure 15

2. Observe the model. Notice that the meshed surfaces give youbetter clarity about the surface contours.

3. Close the MESH dialog box.

4. Repaint the screen.


NOTES

Task 3. View the surface curvature of both the surfaces using theGaussian Curvature tool.

1. To display Gaussian curvature of both the surfaces, click Analysis> Surface Analysis. Select GAUSS CURVATURE from the TYPEdrop-down list.

2. Select surfaces A and B, then click Done Sel.

Figure 16

3. Observe the curvature display. Notice that the surface A displaysthe curvature range from magenta (highest positive) to dark blue(highest negative). The surface B displays the color range fromgreen to orange (mid positive ranges). Also notice the break in thecontinuity of the pattern between surfaces A and B, signifying nocontinuity between the surfaces.

Task 4. Measure the minimum and maximum radii values of surface A.

1. Measure the radii of surface A. Select RADIUS from the TYPEdrop-down list. Select SURFACE. Select Surface A, then clickDone Sel.

2. Observe the maximum and minimum radii values in the RESULTSwindow of the dialog box.

3. To notice the location of the minimum and the maximum radii,change the display of the radii vectors. Click Display; type thenew value [10], then click OK.


NOTES

Figure 17

Task 5. Using offset mesh, evaluate the surface behavior for protrusionor offset.

1. To display the offset mesh of the surface A, select OFFSET MESHfrom the TYPE drop-down list.

2. Define the offset distance that is less than the minimum outsideradius. Type [0.3] as the offset distance.

3. Select the surface A, then click Done Sel.

4. Observe the model. Rotate and zoom the model to carefully viewthe offset mesh. Notice that the mesh is even and not self-intersecting anywhere.

5. Change the offset distance so that it is more than the minimumoutside radius and display the mesh again. Type [0.5], then clickCompute.

6. Observe the model. Notice that the mesh is not proper and is self-intersecting, as shown in the following figure. This indicates thatthe surface created with this offset distance would fail.

Self-intersectingportion

Figure 18



NOTES

Task 6. To study the reflections off the surface, display the reflectioncurves.

1. To display the pre-constructed features defining the light sourceplane and the light source axis, open the REFLECT layer.

2. To display reflection curves, select REFLECTION CURVES fromthe TYPE drop-down list.

3. Select SURFACE. Select surfaces A and B, then click Done Sel.

4. Select a plane to set up the viewing direction. Select PLANE fromthe DIRECTION drop-down menu. Select the PLANE datum, asshown in the following figure. If necessary, use Flip Direction tochange the arrow direction towards the surfaces.

5. Select the light source plane. Select LIGHT SOURCE PLANE fromthe dialog box. Select the LIGHT_SOURCE datum plane, as shownin the following figure.

6. Select the light source axis. Select LIGHT SOURCE AXIS from thedialog box and select AXIS L1, as shown in the following figure.

Figure 19

7. Use a range of light sources to the left and right of AXIS L1 at aspecified distance:

� Click Range from the dialog box.

� Type [3] for distance between lines.

� Type [10] as the number of lines for # on left.

� Type [10] as the value for # on right.


NOTES

8. Click Compute to calculate the results.

Figure 20: Reflection Curves

Task 7. Display the highlight curves.

1. To display Highlight Curves, select HIGHLIGHT CURVES from theTYPE drop-down list.

2. Select SURFACE. Select surfaces A and B and click Done Sel.

3. Select a plane to set up the viewing direction. Select the FRONTdatum plane. If necessary, use Flip Direction to change the arrowdirection, as shown in the following figure.

Figure 21

4. Define the slope angle option. Click Increment, keep the defaultspacing, 5 degrees.

5. Calculate the results. Click Compute.


NOTES

Figure 22: Highlight Curves

Task 8. Save the analysis results for reference.

1. Click Saved Analyses from the SURFACE ANALYSIS dialog boxto expand the area. Type [HIGHLIGHT1] as the name, then

click .

2. Turn off the saved analysis display. Click HIGHLIGHT1, then click

.

3. Close the dialog box.

Task 9. Measure the dihedral angle between the surfaces A and B alongthe common edge.

1. Check the dihedral angle between the two surfaces. Click Analysis> Curve Analysis, then select DIHEDRAL ANGLE from the TYPEdrop-down list.

2. Select the common edge between the two surfaces, then clickDone Sel.

Figure 23


NOTES

3. Observe the results. Notice the numerical results, the maximumand minimum dihedral angles in the CURVE ANALYSIS dialogbox. Also notice the plot that displays the dispersion of thedihedral angle.

4. Close the CURVE ANALYSIS dialog box.

Task 10. Redefine the surface A to make it tangent to surface B, thenmeasure the dihedral angle again and view the saved analysis.

1. Click Feature > Redefine, then select surface A.


3. To specify the tangency condition at the first edge, click Yes.

4. To specify the tangent surface, select surface B.

5. To specify the tangency condition at the second edge, click No.

6. To complete redefining the surface, click OK.

7. To check the dihedral angle, click Analysis > Curve Analysis >Dihedral Angle. Select the same edge as you did previously, thenclick Done Sel.

8. Observe the numerical results in the CURVE ANALYSIS dialogbox. Notice that the maximum and minimum values are zero.

9. Close the CURVE ANALYSIS dialog box.

10. To retrieve the saved analysis, click View > Model Setup >Analysis Display.

11. Click HIGHLIGHT1, then click . Note that the highlightcurves have a smooth transition.


NOTES

Notice the smoothblending curves

Highlights before modifyingthe tangency

Highlights after modifyingthe tangency

Figure 24: The Change in Highlight Curves

12. To hide the saved analysis and close the dialog box, click

> Close.

Task 11. Measure the minimum radius of surface B, then provide athickness that is less than the minimum radius.

1. Measure minimum radii of surface B. Click Analysis > SurfaceAnalysis. Select RADIUS from the TYPE drop-down list. Selectsurface B then click Done Sel.

2. Observe the radii values. Notice that the minimum inside radius is2.7 and minimum outside radius is 5.6.

3. Close the SURFACE ANALYSIS dialog box.

4. Create a thin protrusion. Click Insert > Thin Protrusion > UseQuilt. Select surface B.

5. Click Side 1 to protrude it in the outside direction.

6. To specify the thickness less than minimum outside radius, type[5].

7. To preview the protrusion, click . Notice that the protrusion isnot created.

8. To reduce the thickness, type [1].

9. To preview the geometry, click . Notice that the protrusion isstill not created.


NOTES

10. Click to cancel the feature creation. To confirm the action,click Yes.

Task 12. To understand the reason of protrusion failure, carry out adetailed surface analysis.

1. To display the Gaussian curvature of surface B, click Analysis >Surface Analysis. Select GAUSS CURVATURE from the TYPEdrop-down list.

2. Select the SURFACE. Select surface B, then click Done Sel.

3. To modify the settings, click Computation Settings in SURFACEANALYSIS dialog box to expand it. Click Dynamic Update.

4. To modify the quality, click (if necessary) then drag theslider to somewhere in the center of the bar length.

Sharp change in thecurvature

Figure 25

5. Observe the results. Notice the sharp change in curvature isdisplayed in the middle of the surface.

Task 13. Analyze surface B further using porcupines.

1. Select PORCUPINE from the TYPE drop-down list.

2. Select the surface B, then click Done Sel.

3. To modify the display, click Display, then click Dynamic Update.Rotate the buttons to reduce the height of the display.


NOTES

Figure 26

4. Observe the results. Notice that the surface curvatures are smoothin the magenta direction but the cyan direction displaysirregularity.

5. For better clarity, reduce the magenta curvature display to zero, asshown in the following figure.

Figure 27: Porcupine-Display Settings Dialog Box

6. Close the DISPLAY SETTINGS dialog box and click OK.

7. Modify the computation settings. Click Computation Settings toexpand the box, then click Dynamic Update.

8. To modify the number of points, click from the Resolutioncontainer, then type [75] as the 2nd Direction value.

9. To modify the number of lines, click from the Spacingcontainer, then type [5] as the 2nd Direction value.


NOTES

Figure 28

10. Observe the results. Notice the sharp undesirable changes in thecurvature.

11. Close the SURFACE ANALYSIS dialog box; click Close.

Task 14. Further investigate the problem; analyze the curves.

1. To analyze all the curves of the surface B, click Analysis > CurveAnalysis.

2. Select CURVATURE from the TYPE drop-down list.

3. Select the three curves, then click Compute.

4. Increase the Resolution quality. Click Computation Settings to

expand the box. Click Dynamic Update. Click , then drag theslider bar to the right extreme.

Figure 29


NOTES

5. Observe the results. Notice that the second and the third curves areimproper and have very sharp change in curvature.

6. Close the CURVE ANALYSIS dialog box; click Close.

7. Erase the model from the memory.

Note

You can redefine and modify the curves to improve the surfacequality, but for the scope of this module, you can end theexercise here.


NOTES


• You can use a combination of surface or curve analysis tools to get thedesired feedback.

• Surface tangency can be visualized using many tools like Gaussiancurvature, Section Curvature, Porcupines, Highlight Curves etc.

• Gaussian Curvature and Porcupines are particularly useful indetermining curvature continuity.

• You can use Dihedral Angle to obtain mathematical feedback abouttangency of two surfaces.

• You can use Reflection Curves to determine the aesthetic quality of asurface.

Page 11-1

Module

Surface ContinuitiesIn this module you learn to create curvature continuous surfaces.

Objectives


• Define fundamentals of curvature.

• Define the possible surface continuities.

• Define and create curvature continuous surfaces.


NOTES

THE CURVATUREA curvature is defined as a portion of a surface that is proportional to 1/r atany given point on a curve. The smaller the radius value, the greater thecurvature will be. To detect changes in curvature, you can use acombination of surface information tools available with Pro/ENGINEER.

Figure 1: Varying Curvature of a Spline

When designing surfaces with curvature, keep in mind the following:

• A straight line has a zero curvature since 1/∞ = zero.

• A true arc has constant curvature at all points along the curve, basedon its radius.

• Splines, in general, have constantly changing curvature.

• Geometry can contain inflection points, where the curvature switchesfrom one side of the surface to the other.

Surface Cont inui t ies Page 11-3

NOTES

CONTINUITY BETWEEN GEOMETRIC ENTITIESWhen geometry is joined at a common boundary, the surfaces can meet atthree different levels of continuity:

• G0 – The geometry shares a common boundary. It is discontinuous inboth tangency (slope) and curvature continuity (change in slope).

Figure 2: G0 Continuity

• G1 (Tangent Continuous) – The geometry is both joined and tangent(continuous in slope), as well as discontinuous in curvature.

Figure 3: G1 Continuity

• G2 (Curvature Continuous) – The geometry is joined, tangent, andcontinuous in curvature.

Figure 4: Curvature Continuity


NOTES

USING CURVATURE CONTINUOUS SURFACESTo attain a higher degree of smoothness between the surface patches, youdefine the continuity as curvature continuous (G2). You can create G2surfaces for aesthetic or engineering design such as:

• Exterior panels of products, for example: automobiles with shiny andglossy surface finishes that are painted, chrome-plated, or glass (ClassA surfaces).

• Products that require smooth surfaces to improve fluid-dynamic (oraerodynamic) properties, for example: valves and flow meters.

Creating Curvature Continuous SurfacesCreating curvature continuous surfaces in a given model is dependent onthe existing features that are referenced to create the surfaces. There arelimitations to consider when creating curvature continuous surfaces.

Limitations in Creating Curvature Continuous Surfaces

• To create the curvature continuous surfaces, the references, such ascurves or edges, must have curvature continuity.

• A boundary surface can only be curvature continuous in one direction,as shown in the following figure.

Tangent in the First Direction

Tangent in theFirst Direction

CurvatureContinuous in theSecond Direction

Curvature Continuous inthe Second Direction

Figure 5: Curvature Continuous Boundary Condition

• A surface created between existing curves (edges) in two directionscan not be defined to have a boundary condition of tangent orcurvature continuous, unless all the referenced curves are tangent orcurvature continuous with the adjoining surfaces.


NOTES

Analyzing Curvature Continuous SurfacesIt is a good practice to analyze the results when you create curvaturecontinuous surfaces. You can use the Gaussian Curvature or Porcupinetools to analyze the curvature continuity, as shown in the following figure.

Curvature continuoussurfaces generatecontinuous porcupines

Gaussian Curvature blendssmoothly across thepatches for CurvatureContinuous surfaces

Figure 6: Using Gaussian and Porcupine to Analyze Curvature Continuity


NOTES


In this laboratory, you create and analyze curvature continuous blended

transitions between the surfaces.

Method

In this exercise you finish the shape of a mouse by creating blendedtransitions. You create the transitions so that they are curvature continuouswith the adjacent surfaces.


Done

Repaint the screen

Make selected layers shown

Create an offset entity from an edge

Impose Sketcher constraints

Create same points or collinear constraint


NOTES

EXERCISE 1: Creating Blended Transitions

Task 1. Open the model and show the curves layer.

BlendedTransitions

Figure 7: Model at Beginning and End

1. Open G2_MOUSE.PRT.

2. Show the CONSTRUCTION_CURVES layer. Click View > Layers.

Select CONSTRUCTION_CURVES. Click > > Close.

3. Observe the datum curves in the model. These curves are used tocreate the existing surfaces. These curves will be referenced tocreate additional blended surfaces.

Task 2. Create the first projected datum curve.

1. Create a projected datum curve. Click Insert > Datum > Curve >Projected >Done > Sketch > Done. Select the RIGHT datumplane for the sketching plane.

2. Using Flip, make the viewing direction, as shown in the followingfigure then click Okay. Click Okay for the direction of featurecreation.


NOTES

Figure 8

3. Define the Sketcher horizontal reference. Click Top and select theTOP datum plane.

4. Delete the Sketcher references. In the REFERENCES dialog box,select F2, press <SHIFT> and select F3. Click Delete > Close. Inthe MISSING REFERENCES dialog box, click Yes.

5. Create a curve using Offset Edge. Click . Select the datumcurve, as shown in the following picture.

Align this point andthis edge.

Align this pointto this edge.

Figure 9: Offset Edge for First Curve

6. Type [0.2] as the offset value. If the arrow for the offset directionis pointing up; enter a negative value. Click Close.

7. Align an end point of the offset curve. Click > . Selectone of the end points and edges, as shown in the previous figure. Inthe RESOLVE SKETCH dialog box, select the COINCIDEconstraint, then click Delete.

8. Align the second end point using the method outlined in theprevious step.


NOTES

9. Finish defining the feature. Click to finish the section. Selectthe surface shown in the following picture as the surface forprojection. Click Done Sel > Done > Norm to Sket > Done >OK.

Figure 10: Surface for Projection.

Task 3. Create the second projected datum curve.

1. Click Insert > Datum > Curve > Projected >Done > Sketch >Done. Select TOP for the sketching plane.

2. Using Flip, make the viewing direction, as shown in the followingfigure, then click Okay. Click Okay again for the direction offeature creation.

Figure 11

3. Define the Sketcher horizontal reference. Click Bottom, thenselect the RIGHT datum plane.

4. Delete the Sketcher references. Close the REFERENCES dialogbox. In the MISSING REFERENCES dialog box, click Yes.


NOTES

5. Click . Select the datum curve, as shown in the followingfigure.

6. Type [0.2] as the offset value. If the arrow for the offset directionis pointing down; enter a negative value. Click Close.

Align this endpoint to this

edge.

Align thisend pointand thisedge.

Figure 12: Offset Edge for Second Curve

7. Align the end points of the offset curve using the method outlinedin the previous task.

8. Finish defining the feature. Click to finish the section. Selectthe large top surface shown in the following figure, as the surfacefor projection. Click Done Sel > Done > Norm to Sket > Done >OK.

Figure 13: Surface for Projection

Task 4. Create two datum curves that are tangent and continuous withthe adjacent surfaces.

1. Create the first THRU POINTS datum curve. Click Insert > Datum> Curve > Thru Points > Done.


NOTES

2. Select the two end points of the curves, as shown in the followingfigure. Click Done.

End vertex tangent to edge

Start vertextangent to

edge

Figure 14: First Thru Point Curve

3. Define the tangency at the start of the datum curve. ClickTangency > Define. Retain the menu defaults Start >Crv/Edge/Axis > Tangent. Select the edge for the start vertex, asshown in the preceding figure. If necessary, flip the arrow to pointin the direction shown in the preceding figure. Click Okay.

4. Define the tangency at the end of the datum curve. Retain thedefaults End > Crv/Edge/Axis > Tangent. Select the edge for theend vertex, as shown in the preceding figure. If necessary, Flip thearrow to point in the direction shown in the preceding figure.Click Okay.

5. Define the curvature at the start vertex. Check Curvature.

6. Define the curvature at the end vertex. Click End. CheckCurvature. Click Done/Return > OK to finish the feature.

7. Create the second THRU POINTS datum curve using the methoddescribed in the preceding tasks. Create the datum curve throughthe points and tangent to the edges, as shown in the followingfigure. Define the curvature at the start and end vertex.

Start vertex tangent to edge

End vertextangent toedge

Figure 15: Second Thru Point Curve


NOTES

Task 5. Create a blended surface with continuous boundaries.

1. Click Insert > Surface > From Boundaries > Blended Surf >Done. Keep the defaults and select only the curves for theboundaries in the first direction, as shown in the following figure.

First Direction Curve 1First Direction Curve 2

SecondDirection

Curve 1 Second Direction Curve 2

Figure 16: Blended Surface

2. Define the curves in the second direction. Click Second Dir, thenselect the curves shown in the preceding figure. Click DoneCurves.

3. Define the boundary conditions. Click Bndry Conds > Define >Boundary # 1 > Crvtr Cont > Done > OK. Click Boundary #2 >Crvtr Cont > Done > OK.

4. Finish the feature. Click Done > OK.

Figure 17


NOTES

Task 6. Create another blended surface using two pre-constructedcurves and two curves that you create.

1. Show the BLEND_CURVES layer. Notice the two datum curvesthat appear.

Figure 18

2. Create the first THRU POINTS datum curve. Click Insert > Datum> Curve > Thru Points > Done.

3. Select the two end points of the curves, as shown in the followingfigure. Click Done.


End vertex tangent to edge

Figure 19: First Thru Point Curve

4. Click Tangency > Define. Keep the menu defaults Start >Crv/Edge/Axis > Tangent. Select the edge for the start vertex, asshown in the preceding figure. If necessary, flip the arrow, asshown in the figure. Click Okay.

5. Keep the defaults End > Crv/Edge/Axis > Tangent. Select theedge for the end vertex, as shown in the previous figure. Ifnecessary, flip the arrow to point in the same direction. ClickOkay.


NOTES

6. Define the curvature at the start vertex. Check Curvature.

7. Define the curvature at the end vertex. Click End. CheckCurvature. Click Done/Return > OK to finish the feature.

8. Create the second THRU POINT datum curve. Create the datumcurve through the points and tangent to the edges, as shown in thefollowing figure. Define the curvature at the start and end vertex.

End vertextangent to edge


Figure 20: Second Thru Point Curve

Task 7. Create a blended surface.

1. Click Insert > Surface > From Boundaries > Blended Surf >Done. Keep the defaults and select the curves for the boundariesin the first direction, as shown in the following figure.

First Direction Curve 1 First Direction Curve 2

SecondDirectionCurve 1

SecondDirection

Curve 2

Figure 21: Second Blended Surface

2. Define the curves in the second direction. Click Second Dir andselect the curves, shown in the preceding figure. Click DoneCurves.

3. Define the boundary conditions. Click Bndry Conds > Define >Boundary # 1 > Crvtr Cont > Done > OK.

4. Click Boundary #2 > Crvtr Cont > Done > OK.


NOTES

5. Finish the feature. Click Done > OK.

Task 8. Merge all of the surfaces together and analyze the curvature ofthe mouse.

1. Merge the first blended surface with the mouse quilt, and thenmerge the second blended surface with the quilt.

2. Click Analysis > Surface Analysis. Select GAUSS CURVATUREas the type. Select the all of the surfaces across the top of themouse, then click Done Sel.

Figure 22: Gaussian Surface Analysis

3. Notice the curvature pattern. Notice that the transition surfacesdisplay a continuous pattern the adjacent surfaces signifying thecurvature continuity.

4. Save the model and erase it from the memory.


NOTES


• By providing curvature continuity, the surfaces join smoothly.

• Creating curvature continuous surfaces is dependent on the boundariesused to create the surfaces.

• You only need to provide curvature continuity when specific designintent is required.

Page 12-1

Module

Additional Advanced Surfacing ToolsIn this module you learn how to use additional advanced surfacing

tools.

Objectives


• Define additional advanced surfacing options.

• Create a draft surface using the Tangent-to-Surface option.

• Create free form features.


NOTES

USING ADDITIONAL SURFACING OPTIONSThe following advance surfacing options enable you to capture specificdesign intents such as:

• Section to Surface

• Surface to Surface

• Tangent to Surface

• Free Form

SECTION TO SURFACEThe Section to Surface option enables you to create a transitional surfacebetween a set of tangent surfaces and a sketched contour. To use theSection to Surface option:

• The set of surfaces selected for the tangent boundary must be closed.

• The sketched section or the selected edges must be closed.

Step 1 Step 2

Step 3 Step 4

Tangent Surface

Section

Figure 1: Using the Section-To-Surface Option

Some More Surfac ing Too ls Page 12-3

NOTES

TANGENT TO SURFACEThe TangentToSrf option enables you to create a quilt tangent to asurface and originating from a draft line. To use TangentToSrf option,you define:

• A draft line, using an edge or a datum curve.

• The pull direction, using a planar surface or datum plane.

• A tangency point.

Select this curve todefine draft line

Select this surface todefine pull direction

Select this surface todefine tangency point

Resultant draft surface

Figure 2: Using the Tangent-To-Surface Option


NOTES

SURFACE TO SURFACEThe Surface to Surface option enables you to create a smooth transitionbetween two surfaces, as shown in the following figures. To use theSurface to Surface option:

• The surfaces must be inclined toward each other by at least a 30°angle.

• The surfaces must have matching tangency points for each point ontheir surfaces.

Figure 3: Using the Surface to Surface Option


NOTES

FREE-FORM SURFACE FEATURESUsing the Free Form option, you can dynamically manipulate a surface.You can push or pull on a surface—interactively changing its shape tocreate a new surface feature or modify a solid or quilt. Whenever theunderlying surface changes shape, the free-form feature also changesshape proportionally. While creating a free-form feature, you can select anentire surface or sketch a region.

Figure 4: Manipulating the Entire Surface

Figure 5: Manipulating the Sketched Regions

Using FreeformTo create a Free Form feature, you need to define the:

• Base Surface

• Grid

• Manipulate Options

Figure 6: Dense or Sparse Grids


NOTES

Defining Manipulate OptionsThe Manipulate option in the Free Form dialog box, enables you to dragthe control points in order to manipulate the shape of the surface. You cancontrol the movement of the points by defining the following options inthe MODIFY SURFACE dialog box:

Movement Plane

You can drag the points with reference to one of the following planes:

• Dynamic Plane – The movement plane is a tangent plane that passesthrough the selected point. The dynamic movement plane follows theselected point.

• Defined Plane – Select a datum plane to be the movement plane.

• Original Plane – The movement plane is a tangent plane that passesthrough the original location of the selected point.

Movement Direction

You can specify the following directions for the point movement:

• First

• Second

• Normal

Region

While moving the points you can define the Poly Motion region usingfollowing options:

• Smooth

• Linear

• Constant


NOTES

Using Dynamic DiagnosticsWhile modifying the shape of a surface, you can turn on or off thedynamic display of analyses and diagnostic tools. The dynamic displaychanges as you change geometry.

You can use the following diagnostics options:

• Slope

• Section Curvature

• Cosmetic Shading

• Normal

• Porcupines

• Mesh

Figure 7: Using Porcupines to Diagnose

Figure 8: Using Mesh to Diagnose


NOTES


In this laboratory, you use additional surfacing options to create and

manipulate surfaces.

Method

In the first exercise you create a draft surface using the Tangent toSurface option. To define the surface, you use a sketched curve and anedge round.

In the second exercise, you change the shape of the top cover of a mobilephone using the Free Form option. You modify the base surface to createanother free form surface feature, then replace the base surface with themodified surface.


Build Feature

Show/Blank selected areas

Create an offset entity from an edge

Insert a feature here

Done

Quality

Number of points


NOTES

EXERCISE 1: Creating Draft Surfaces of a Boss

Task 1. Open model and observe the features.

1. Open DRAFT.PRT.

RibBoss

Figure 9: The Flange Part

2. Observe the model. A rib has already been added to the boss andpatterned rotationally. Notice that the ribs and the boss havealready been rounded.

3. Observe the Model Tree. Expand the pattern in the Model Tree.Expand the first group in the pattern. The first rib was created andthen a round was applied to the edges of the rib. These twofeatures were then grouped together and patterned.

Task 2. Attempt to draft the boss and ribs.

1. To create a draft for the boss and ribs, click Insert > Draft >Neutral Pln > Done > Tweak > No Split > Constant > Done.

2. To select the draft surfaces, click Loop Surfs. Select the surface,and then select the edge, as shown in the following figure. ClickDone.


NOTES

Select this surface

Select this edge

Figure 10: Attempted Draft

3. Select the same surface shown in the preceding figure for theneutral plane. Click Use Neut Pln. Type [–5] for the draft angle.Click Preview.

4. Notice the draft was aborted. Cancel the draft feature. ClickCancel > Yes.

Note:

The rounds on the model caused the draft to fail. Draft shouldusually be applied before the rounds are added to the model.As an alternative to inserting the draft before the rounds, thesurfaces can be used to provide draft to a model that hasalready been rounded.

Task 3. Create a datum curve to represent the draft line.

1. Click Insert > Datum > Curve > Sketch > Done.

Figure 11


NOTES

2. Select the surface shown in the preceding figure for the sketchplane. Click Okay > Bottom. Select DTM3 as the reference plane.

3. Delete the references from the REFERENCES dialog box.

4. Click > Yes. Click Loop and select the surface shown in theprevious figure. Click Next until the edges of the boss arehighlighted. Click Accept and type [2] as the offset distance.

5. Sketch a circle on top of the offset entities, as shown in followingfigure.

Sketch a circle here.

Figure 12: Sketching a Datum Curve

6. Finish the curve. Click > OK.

Task 4. Create a draft on the boss and ribs using surface features.

1. To create a surface, click Insert > Surface > Blend Tangent ToSurfaces.

2. Click One By One > Query Sel. Select the circle. Toggle throughthe QUERY BIN until only the circle is highlighted. Click Accept> Done Sel > Done.


NOTES

Select this surface forthe pull direction

Select this surface to be tangent

Figure 13

3. To define the pull direction, select the surface shown in thepreceding figure. Click OK to accept the default direction.

4. Define the approximate tangent location. Click Options > Define> Full Tangency > Done. Select the round surface for theapproximate tangent location, as shown in the preceding figure.

5. Click OK to finish the surface creation.

Select thesecurve segments

Figure 14

6. Create the draft surface for the right rib. Click New > Advanced >Done > TangentToSrf > Done.

7. Click One By One. Select the segments of the offset datum curve,as shown in the preceding figure. Click Done Sel > Done.

8. Select the surface for the pull direction. Click OK to accept thedefault direction, as shown in the following figure.


NOTES

9. Define the approximate tangent location. Click Options > Define> Full Tangency > Done. Select the round surface for theapproximate tangent location, as shown in the preceding figure .

Select roundsurface

Figure 15

10. Click OK to finish the surface creation.

11. Repeat the procedure outlined in the previous steps to create thedraft surfaces on the other two ribs.

Figure 16: Model after Draft Remaining Ribs



NOTES

EXERCISE 2: Free Form Manipulation

Task 1. Open the model. Create a freeform feature and start tomanipulate the shape.

1. Open PHONE_TOP_COVER.PRT.

Figure 17: The Original Shape

2. In the Model Tree, drag [Insert Here] between PROTRUSION ID2062 and CURVE ID 297 in the Model Tree.

Figure 18: Protrusion Feature


NOTES

3. To create a free form feature of the base surface, click Insert >Surface > Freeform.

4. Define the base surface for modification. Select the top surface ofthe protrusion.

Figure 19: Modifying Base Surface

5. Type [7] for the number of control curves in the first direction.

6. Type [7] for the number of control curves in the second direction.

Task 2. Turn on the diagnostics to view the porcupines and mesh whilemodifying the surface.

1. In the MODIFY SURFACE dialog box, click Diagnostics toexpand the dialog box.

2. Click Porcupine > .

3. Change the display options of the porcupine. In the DIAGNOSTICSarea, click Computation. In the COMPUTATION dialog box, selectthe Dynamic update check box.

4. To change the resolution, in the RESOLUTION area, click .Move the first and second direction sliders to the right to increasethe quality.


NOTES

5. In the SPACING area, click . Modify the number of lines to 7in both directions.

6. Click OK to close the COMPUTATION dialog box.

7. To change display settings, in the DIAGNOSTICS area, clickSetting.

8. In the DISPLAY SETTINGS dialog box, select the DynamicUpdate check box.

9. Change the value to 2 in both the directions, then click OK.

Figure 20

10. To display mesh, in the DIAGNOSTICS area, click Mesh >

.

Task 3. Move the points to modify the shape of the top-cover.

1. To define the movement plane, select Defined Plane from theMOVEMENT PLANE list. Select the TOP plane.

2. To define the movement direction, select the Normal check boxand clear other check boxes.


NOTES

Raise the points aroundthis zone

Lower the points around this zone

Figure 21: Modifying Shape

3. Drag the points in order to modify the shape of the model. Depressthe surface slightly in the keypad area and raise the surface arounddisplay area, as shown in the preceding figure. Use porcupines tocontrol the change in the shape. If necessary, rotate the modelwhile modifying the shape.

4. To finish modifying the free form feature, click > OK.

Figure 22: Final Shape


NOTES

Task 4. Create an offset feature of the free form quilt then replace theoutside and the inside solid surfaces with the quilt and the offset quilt.

1. To offset the free form quilt, click Insert > Surface > Offset.Select the quilt then type the offset thickness [3]. Create the offsetsurface towards inside, as shown in the following figure.

Figure 23: Direction of Quilt Offset

2. Click to finish the offset creation.

3. To replace the outside solid surface, click Insert > Advanced >Replace Surfaces. Select the outside surface to replace.

4. Select the freeform quilt (outside) as the replacement quilt.

5. Click OK to finish replacing.

6. Using the same method, replace the inside solid surface with offsetquilt.

Task 5. Resume the suppressed features.

1. Click Feature > Insert Mode > Cancel, then click Yes. Wait untilthe model regenerates.


NOTES

Figure 24: Model with Features Unsuppressed


Note

You can also accomplish this exercise with the Tweak, FreeForm tool. The Tweak tools do not create a new feature butenable you to modify the solid surfaces. In this case, it is notnecessary to replace the model surfaces as you did in theexercise. Also the Tweak, Free Form enables you to selectmore than one surface to modify.


NOTES


• To create a tangent surface between a curved surface/surfaces and asketched section, you can use the Section-to-Surface option.

• To create a draft surface between a draft line and a curved surface, youcan use the Tangent-to-Surface option.

• To create a smooth transition between two surfaces, you can use theSurface-to-Surface option.

• To dynamically push or pull on a surface and interactively change itsshape, you can use the Free Form option.

Page 13-1

Module

Working with Imported SurfacesIn this module, you learn how to use import surfaces.

Objectives


• Define the use of the imported surfaces.

• Define the methods to work with imported surfaces.

• Fix the problem surfaces.


NOTES

WORKING WITH IMPORTED SURFACESYou can import various surface data including:

• Standard library parts, such as surface data from another CAD system.

• Surface geometry created by another department or company.

You can use the imported surfaces to:

• Create a solid model.

• Replace a solid surface.

• Replace an imported surface.

Creating a Solid Model from Surface Data

You can convert imported surface data into a solid model using thefollowing methods.

• If the individual quilts are merged as a single closed volume, you useProtrusion, Use Quilts� and Solid to create the solid feature.

• If the system displays the imported feature as an open quilt that cannotenclose a single volume, you use Protrusion, Use Quilts, and Thin tocreate a thin solid.

Replacing a Single Solid Surface with an Imported Quilt

If you import a styled surface into a working model, you can use thesurface to define solid geometry. Using Tweak and Replace, you can addmaterial and remove material simultaneously. This enables you to replacea single solid surface with a complex surface quilt.

Replacing & Updating Imported Surfaces

You can replace an imported surface feature with a new import filewithout a one-to-one correspondence between existing entities and thereplacement entities. The system prompts you to pair all entities of theimport feature referenced by any other features, both internal and externalto the part. Using the following options, you can replace all types ofimported geometry, such as wireframe, surfaces, edges, quilts, and datumpoints.

Work ing wi th Imported Surfaces Page 13-3

NOTES

You can:

• Replace the entire feature with the new import file using the ReplaceAll option.

• Replace selected parts of the feature with a new import file using theReplace option.

• Add or append the new geometry to the existing surface geometryusing the Add option.

Working MethodYou can use an imported 3-D wireframe, 3-D surface, or a combination ofthese data types to check a solid feature.

To use imported data in Pro/ENGINEER, you can use the following basicmethods:

• Use the geometry as imported. – If the geometry comes from astandard library of parts or from another department or company, thenyou may want to use the feature without changing it.

• Modify geometry non-parametrically. – If the geometry is modifiedoccasionally, you can modify the imported entities non-parametrically; for example, change the bend angle of a wireframebracket or move a snap mount on a surface model.

• Create/recreate only the important geometry. – If certain sectionsof the geometry need to be modified frequently, you can re-create onlythose sections. For example, a part used as a housing for electronicsmay need to attach to many different versions of the product.

• Re-create an entire model parametrically. – If the importedgeometry is altered extensively, it may be more efficient to re-createthe entire part, so that you can benefit from all of the advantages ofassociativity by capturing the design intent and using a feature-baseddesign.

WORKING WITH PROBLEM SURFACESOccasionally, imported geometry contains inconsistencies in topology ordiscontinuities in geometric entities. Pro/ENGINEER offers a set of toolsto repair these problems. You can repair these problems:

• During import of the surfaces.

• After import of the surfaces.


NOTES

Identifying Problematic SurfacesWhen you import surface geometry from another system, Pro/ENGINEERcreates both joined and untrimmed surfaces. The system displays theboundaries of imported surface geometry in two colors:

• Yellow – Represents the old or existing edge of a surface that yourepair.

• Orange – Represents the edge of the surface that you are actuallyrepairing by editing, modifying, or creating new orange edges.

These orange edges are modified,leaving a yellow edge behind

Figure 1: Orange and Yellow Edges


NOTES

Repairing Problems during ImportBy setting the following CONFIGURATION FILE options, you can instructPro/ENGINEER to repair the problematic boundaries of imported surfacesduring the import process:

• fix_boundaries_on_import – When set to yes, the systemautomatically attempts to fix the boundaries of imported surfaces as itis reading them in.

• intf3d_in_close_open_boundaries – When set to yes, thesystem attempts to close open trimming boundaries of importedsurfaces by connecting the endpoints across the gaps, adding edges.

Using the Geometry Check Tool after Import

Pro/ENGINEER checks for geometry errors during import and, ifnecessary, automatically activates the Geometry Check tool to identifyproblems with features. Before you repair imported surface geometry, youcan use this information tool to view problematic features in thePro/ENGINEER Main Window and review their definitions.

The GEOMETRY CHECKS dialog box lists the problematic features,provides the feature information, indicates the cause of the problem, andoffers possible solutions. By selecting the entity name in the dialog box,you can highlight the problematic entities in the GRAPHICS window. Ifnecessary, you can then create a note with arrows inside the Main Windowto identify the problem.


NOTES

Figure 2: Geometry Check Tool

Repairing the Imported GeometryAs an initial step, you can join surfaces using the Zip Gaps tool to closegaps between surfaces automatically. If, after zipping the gaps, theGeometry Check information tool identifies remaining problems with thesurface geometry, you can redefine the boundaries in various ways, aswell as exclude, delete, or create additional geometry, if necessary.

The following figure depicts the entire process to successfully repairproblematic surface geometry after import. Throughout the redefinitionprocess, however, you should repeatedly check your progress using theGeometry Check and Zip Gaps tools.


NOTES

Figure 3: Process for Repairing Problematic Surfaces

Using the Zip Gap Tool

After you import surfaces, the system may display some surfaces in themodel as one-sided surface edges (edges that are not shared by anothersurface) in yellow. Using the Zip Gap and Auto Select options, you canautomatically match yellow edges and join surfaces together.

Pro/ENGINEER automatically selects and highlights all of the pairs ofedge chains that fall within the tolerance of MaxGapDist. It then matchesthe surfaces along those chains and enables you to preview the newsurfaces.

You can add additional edges manually using Sel Chain, Single, orChain. However, if you are not satisfied with the results of the automaticsearch, you can reset the selection criteria and use Auto Select again. Byincreasing the maximum value of the selection range, you can force thesystem to include larger gaps in the selection.


NOTES

Tips & Techniques:

When setting the value of MaxGapDist, use the accuracylevel of another system, since the gap is probably smaller thanthat value. Occasionally, the system measures the largest gapin the selected edges that it cannot fix, then suggests a valuethat is slightly larger. The best practice is to accept the fixedgeometry for as many boundaries as possible at a given value,raise the value if you cannot fix some selected edges (or someproblem edges are not selected), then use Auto Select again.

Redefining Surface Boundaries

After you use the Zip Gap tool, you may still need to repair someimported surface boundaries manually. Using the Fix Bndries option inthe REDEF IMPT menu, you can alter the trimming boundaries of asurface. You can:

• Manually alter the trimming boundary of a surface.

• Automatically repair some internal quilt vertices, manually repair allincorrect vertices that the system does not automatically repair, andmove vertices in a set for better alignment.

• Convert a multi-segment quilt boundary to a single edge.

• Check surfaces tangent along selected edges, improving the quiltcontinuity.

Also, you can modify a selected chain of edges, combine two chains ofedges into one, delete an edge from a chain, or create a new chain of edgeson the surface.

Tips & Techniques:

The Fix Bndries procedure is non-parametric and, therefore,irreversible. To undo your changes, save your file frequently,re-import the entire file, or re-import only a portion of thegeometry.

Modifying an Existing Chain of Edges

When editing an existing boundary, you should always try to modify theexisting chain of edges before re-creating a new chain of edges. Usingvarious options, you can make the following changes:


NOTES

• Move the vertex – You can place a vertex of the chain at a newreference point. The system then straightens the edges at the vertexand removes any preexisting tangency conditions at that vertex.

• Straighten an edge – You can replace a chain of edges with a simpletwo-point edge.

• Merge edges – You can merge the chain of edges into one continuousedge.

• Set the tangency condition – You can set or change tangencyconditions for the edge. The system marks the start and endpoints ofthe edge with corresponding arrows. You can make the edge tangent toa reference at the selected end, normal to a reference at the selectedend, or remove the requirement for the edge to be tangent or normal toa reference at the selected end.

• Split the edge – You can divide the edge into two edges at a selectedpoint. There are no tangency conditions between the two new sub-chains at that point.

Note:

You must replace a single open chain with a single open chain,or a single closed loop with a single closed loop before youexit the EDIT BNDRY menu; otherwise the system aborts thecurrent edit boundary procedure.

Move the vertex tonew location

Figure 4: Moving a Vertex


NOTES

Straighten edge

Figure 5: Straightening an Edge

Remove additional points

Figure 6: Merging Edges

Fixing Quilt Vertices

Using the Fix Vertices option, you can require the system to inspect allpoints on the imported part at which purple or yellow edges meet andidentify those areas that may cause problems later. In addition toinforming you of where the problems may occur, it also attempts to movevertices together to achieve better alignment.

Fixing Quilt Boundaries

Instead of searching for misaligned edges, you can automatically find quiltboundaries (chains of one-sided edges, colored yellow) composed ofmultiple segments that are almost tangential and nearly an isoline. Youcan fix all of the fragmentations and inaccuracies in the yellow edges byautomatically replacing them with surface isolines.


NOTES

Additionalvertex isremoved

Figure 7: Fixing Quilt Boundary

Fixing Tangency

You can improve the tangency of imported data by making surfacestangent along selected edges. The angle at which surfaces join is referredto as the dihedral angle. If the surfaces are meant to be tangent, the angleis very small or zero.

You can apply tangency only to small dihedral angles (that is, those thatare less than 10 degrees). The system automatically selects the edges thatare within the tolerance MaxDihedral and highlights them in blue.

You can add more edges manually using Sel Chain, Single, or Chain. Ifyou are not satisfied with the results of the automatic search, you can resetthe selection criteria and use Auto Select again. By increasing themaximum value of the selection range, the system will include largerdihedral angles in the selection.

Note:

The Fix Bndries tool automatically selects all problemboundaries based on the value of MaxDihedral. The systemdoes not automatically select boundaries that have gaps. Youshould use this method to repair a quilt that is completelyzipped and has fixed vertices.

Tips & Techniques for Editing Boundaries

When editing boundaries, follow these practices:

• Remember that the Fix Bndries procedure is nonparametric. Thisprocedure is not reversible. To undo your changes, re-import the file.

• Save the part often. You cannot undo changes after you exit the EDITBNDRY menu.

• Select accurately. Use Query Select to select the appropriate entities.


NOTES

• Modify whenever possible. Use the Modify option in the EDITBNDRY menu to change the existing edges rather than create newones.

• Always project edges onto the surface. You cannot create or modifyedges so that they are off of the surface. All new edges that you createand old edges that you modify should always project onto the surface.

• Exclude surfaces, if necessary. If you cannot repair a boundary orvertex using Fix Bndries, exclude the incorrect imported surfaces andblank them on a layer. Recreate new surfaces in Pro/ENGINEER andmerge them into the imported quilt.

• Fix edges manually, if necessary. If the Geometry Check informationis not available for a particular problem, isolate the problem area byfixing edges one at a time manually. With remaining problem edges,use the preceding techniques.

• Use available tools to investigate problems. Use the analysis toolsprovided by Pro/ENGINEER to investigate any problem geometry:

• Mesh surfaces to improve viewing. Cosmetic meshes can be helpful inimproving your view of surfaces that you need to edit.

Creating a New Chain of Edges

If you cannot modify an existing boundary, you can create a new chain ofedges by using any of the following methods:

• Projecting a curve or a chain of edges onto the surface.

• Connecting two or more points.

• Creating an isoline through a reference point.

• Intersecting the selected surface with another surface.


NOTES

Project theseedges onto the

problem surfacewith orange

edges

Figure 8: Projecting

Connect two ormore points

Figure 9: Connecting

Deleting Imported GeometryBecause of variances in the way other systems create geometry, coincidentsurfaces are a common problem with imported data. Often, surfaces liedirectly on top of each other, which prevents them from joining correctly.When you redefine the imported geometry, you can delete points, datumplanes, curves, or surfaces.

Note:

If you delete an entity from the imported geometry, the systempermanently removes this entity and you cannot undo theoperation.


NOTES

Excluding SurfacesInstead of using delete to remove a problematic imported surface, you cansimply exclude the surface. Since you do not permanently remove thesurface from the model, you can use it again in the future, if necessary.This method is particularly useful for resolving situations in which twosurfaces lie directly on top of each other, preventing them from joining therest of the quilt correctly. Pro/ENGINEER joins all other surfaces in thearea, with the exception of the one that you excluded.


NOTES


In this laboratory, you repair a problematic IGES surface and convert it

into a solid protrusion.

Method

In this exercise, you import an IGES file that is problematic then close thegaps using automatic selection of the imprecise surfaces. You manuallycorrect the boundaries of rest of the surfaces that are not corrected by autoselection.


Build feature

EXERCISE 1: Fixing Imported Surface Boundaries

Task 1. Create a new model using the ZIP.IGS file.

1. Click File > New. Type [zip_gaps] as the name, then click OK.

2. Click Insert > Data from File. Locate and select the ZIP.IGS filefrom the OPEN dialog box, then click Open.

3. Retain the default co-ordinate system and click OK in theCHOOSE SOLID OPTIONS AND PLACEMENT dialog box.

4. Review the INFORMATION WINDOW and close the window.

5. Observe the model in the wireframe mode. Notice that the modelcontains a number of unstitched surfaces having open (yellow)edges.


NOTES

Figure 10: The Imported Geometry

Task 2. Activate the Geometry Check to explore the information toolsand review the recommendations.

1. Click Info > Geometry Checks, then click Item #1. Read themessage displayed in the dialog box.

Figure 11: The Message in the GEOMETRY CHECKS Dialog Box

2. View the note associated with the problem. In the GEOMETRYCHECKS dialog box, click Show Note. The system displays anote attached to the area of problem.

3. Close the GEOMETRY CHECKS dialog box. Click Close.

Tips & Techniques:

You can also use the Item Info icon to read the same messagein a separate window.


NOTES

Task 3. Repair the quilt following the recommended action; firstremove the Join Surfs attribute and close all of the small gaps in thesurfaces.

4. Redefine the import feature. Click Feature > Redefine; then selectanywhere on the quilt.

5. Click Attributes, clear the Join Surfs option, and then clickDone/Return.

6. Close the gaps. Click Heal Geometry > Manual > Zip Gaps >Auto Select. Accept the selection. Click Zip Gaps.

Note:

When you use the Auto Select option, the systemautomatically selects all problematic boundaries based on thevalue of MaxGapDist. Once it has completed the selection, ithighlights the edges in blue. You can then add more edgesmanually using Sel Chain, Single, or Chain.

7. Use the geometry check tool to view the new warnings:

� Click Geometry Checks from the Info pull-down menu.

� In the GEOMETRY CHECKS dialog box, select Item #1and read the message in the dialog box.

� Similarly, select Item #2, Item #3, and Item #4 one afteranother and read the messages.

� Close the GEOMETRY CHECKS dialog box. Click Close.

8. Accept the changes and finish closing the gaps. Click Accept >Return > Done/Return.

9. Click Attributes, then select the Join Surfs check box, and thenclick Done/Return to reselect the Join Surfs attribute.

10. Click Done to finish correcting the surfaces.

11. Save the model.

Task 4. Examine the model that is corrected.

1. Examine the model. Notice that the some of the surfaces, shown asmeshed in the following figure, still have open edges and have not


NOTES

been stitched to the main quilt. Zoom in to view the open surfacesclosely, if necessary. Use mesh to visualize the problem better.

Figure 12: Open Surfaces Unstitched to Quilt

Task 5. Start to repair the first surface. Create new boundaries of theextended surface to match with the quilt using the intersect tool.

1. Redefine the import feature. Click Feature > Redefine, then selectthe imported geometry.

2. Edit the boundaries of the curved surface. Click Heal Geometry >Manual > Edit Bndry. Select the surface, shown as meshed in thefollowing figure.


NOTES

Figure 13

3. Click Sel Contour > Select All to select the contours.

4. Create an intersect boundary with the front vertical surface. Retainthe default Create in the EDIT BNDRY menu and click Intersectfrom the CREATE menu. Select the front vertical, as shown in thefollowing figure.

Select this surface

Figure 14

5. Create another intersect boundary, but use the back verticalsurface. Click Intersect and select the hidden rear vertical surface,as shown in the following figure.


NOTES

Use query select toselect the back surface

Figure 15

6. Delete the original boundaries. Click Delete and select one of thetwo original orange edges. Click Delete again and select the otheredge.

Delete these two originalorange edges (select theouter orange edges)

Figure 16

7. Combine the resulting edges. Click Combine. Select one of thenew curves; then select one of the smaller curves at the end.

Combine these twoorange edges

Figure 17


NOTES

8. Repeat this procedure to combine the edges shown in the followingfigure.

Combine these twoorange edges

Figure 18

9. Combine the remaining edge, as shown in the following figure.

Combine this last edge tothe rest of combined edges

Figure 19

10. Click Preview to preview the resulting geometry. Notice that thecombined edges are highlighted in red color.

11. Accept the change; click Done > Done-Return > Done/Return >Done.

12. Save the model.

Task 6. Repair the flat rectangular surface at the front by trimming thesurface correctly.

1. Redefine the Import feature.


NOTES

2. Edit the boundaries of the flat surface. Click Heal Geometry >Manual > Edit Bndry. Select the surface, shown as meshed in thefollowing figure.

Figure 20

3. Click Sel Contour > Select All.

4. Reposition the vertices of the surface correctly: Click Modify >Move Vertex. Select any one of the orange vertexes, then selectthe yellow vertex closest to the first selection.

5. Observe the change. Notice that the orange edge updates to reflectthe new selection.

Move this orangecross vertex to thenext yellowvertex

Figure 21


NOTES

6. Continue to reposition the other three vertices using the sameprocess.

7. Click Preview to preview the resulting geometry. Notice that thecombined edges are highlighted in red color.


9. Save the model.

Task 7. Repair the flat triangle surfaces at the front by trimming themcorrectly.

1. Redefine the import feature.

2. Edit the boundaries of the triangular surface. Click Heal Geometry> Manual > Edit Bndry. Select the surface, shown as meshed inthe following figure.

Figure 22


4. Reposition the right vertex correctly. Click Modify > Move Vertex,then select the lower right orange vertex and the yellow vertexclosest to the first selection.


NOTES

Select this vertex

Figure 23

5. Preview the result and accept it. Click Preview > Done.

Figure 24: Repositioned Vertex

6. Create a new boundary by projecting the boundary of the topadjacent surface. Click Sel Surface, and then select the sametriangular surface again.

7. Click Sel Contour > Select All. Retain the default Create andclick Project.

8. Select the top yellow edge that is inside the orange loop, then clickDone Sel.

9. Repaint the screen. Note that Pro/ENGINEER creates the neworange line along the selected yellow edge.

10. Delete the original boundary. Click Delete, and then select theoriginal lower orange edge, as shown in the following figure.


NOTES

Select this edge todelete

Figure 25

11. Combine the boundaries. Click Combine. Select the new orangecurve, and select one of the original curves.

12. Click Preview and notice that the combined edges are highlightedin red color.


14. Save the model.

Task 8. Repair another surface at the bottom right of the importedgeometry by straightening the edges.


2. Edit the boundaries. Click Heal Geometry > Manual > EditBndry. Select the surface shown as meshed in the following figure.

Figure 26


NOTES


4. Zoom in to the problematic area. Note that this surface has edgesthat are not straight.

Select these points

Figure 27

5. Straighten the right vertical edge. Click Modify > Straighten.Select the orange point at the lower right corner of the surface andthe orange point at the upper right corner, as shown in thepreceding figure.

6. Check the edge between the selected points is highlighted in red,and then click Accept. Note that the screen updates the orangeedge.

7. Straighten the left vertical edge using the procedure outlined inabove step.

8. Click Preview to preview the resulting geometry.


10. Save the model.

Task 9. Repair the rectangular surface to the right of the model bycreating isolines rather than repositioning the vertices.


2. Edit the boundaries of the surface to the right. Click HealGeometry > Manual > Edit Bndry. Select the surface shown asmeshed in the following figure.


NOTES

Figure 28


4. Create a new lower boundary. Retain the default Create and clickMake Isoline. Select the right bottom vertex, as shown in thefollowing figure.

5. Using Next, change the arrow direction, as shown in the followingfigure. Click Accept.

Select this vertex

Figure 29

6. Create another isoline. Click Make Isoline , then select the vertexshown in the following figure.


NOTES

Figure 30

7. Use the same method to create next two isolines lying on top of theyellow edges.

Figure 31

8. Delete the original boundaries.

Figure 32


NOTES

9. Combine all the isolines that you have created.

Figure 33

10. Accept the change; click Done > Done-Return > Done/Return.

Task 10. Use the Zip Gaps functionality to stitch the remaining yellowboundaries. Create a solid out of the stitched quilt.

1. Use the Zip Gaps functionality to fix the remaining yellowboundaries. Click Heal Geometry > Manual > Zip Gaps > AutoSelect > Zip Gaps > Accept > Return > Done/Return > Done.

2. Create a solid protrusion. Click Insert > Protrusion > Use Quilt.

Select anywhere on the quilt, and then click .

Figure 34: The Final Solid Model



NOTES


• You can use imported data to:

� Create a solid model.

� Replace a solid surface.

� Replace an imported surface

• You can use the following methods to work with imported data:

� Use the geometry as imported.

� Modify geometry non-parametrically.

� Create/recreate important geometry only

� Re-create an entire model parametrically.

• Pro/ENGINEER checks for geometry errors during import and offerspossible solutions to fix the problems.

• Pro/ENGINEER also offers possible solutions while you are fixing theproblems.

• Pro/ENGINEER offers many tools to:

� Close gaps.

� Redefine surface boundaries.

� Fix tangency.

Page A-1

Appendix

Additional ExercisesIn this module, you practice with advanced surface design methods.

Objectives


• Create an involute surface using relations.

• Create a gear sector using involute surfaces to cut the gear profile.

• Create a helical cut using variable section sweep.

• Create a complex round using surfaces.

Page A-2 Des igning w i th Surfaces

NOTES

LABORATORY PRACTICAL

EXERCISE 1: Creating a Gear SectorGoal

In this exercise, you cut involute gear profiles in solid gear block.

Method

In this exercise, you create a surface with involute profile using variablesection sweep and relations, a gear tooth by cutting the solid from thesurfaces and then making the rest of the gear teeth by group pattern.

Task 1. Open the model and create a datum plane on an angle of 20degrees to TOP datum plane.

1. Open INVOLUTE.PRT.

Figure 1: The Gear Sector without the Teeth

2. Create a datum plane. Click Insert > Datum > Plane > Through.

3. Select axis A_1, click Angle, select TOP, and then click Done.

4. Click Enter Value, type [20] as the number of degrees, and then

click .

Addi t ional Exerc ises Page A-3

NOTES

Specify the backsurface to sketch thevariable section sweep

Figure 2

Task 2. To define the involute profile of the gear tooth, create aninvolute surface using the variable section sweep tool.

1. Create a variable section sweep surface normal to the origintrajectory. Click Insert > Surface > Variable Section Sweep >Normal To Origin Traj > Done.

2. To sketch the origin trajectory, click Sketch Traj.

3. Specify the sketching plane; select the back surface, as shown inthe preceding figure.

4. Define the viewing direction as shown in the following figure, andthen click Okay. If necessary, use Flip to change the direction.

Figure 3


NOTES

5. Specify the reference plane. Click Top and select DTM1 as thereference plane.

6. Specify the Sketcher references; select DTM1 and A-1 axis.

7. Sketch a concentric 14-degree arc that starts 3 degrees fromDTM1. Use a centerline to dimension the 3-degree angle, as shownin the following figure. Check that the start point is located on thelower end of the arc.

Figure 4


9. Click Sketch Traj to specify the x-trajectory.

10. Click > Default to return to the default view.

11. Specify the sketching plane. Select the front face as the sketchingplane, shown as meshed in the following figure, for the x-trajectory.


13. Click Top and select DTM1 to specify the reference plane.


NOTES

Figure 5

14. Specify the Sketcher references; select DTM1 and A-1 axis.

15. Create the same sketch as created in the previous step.

Tips & Techniques:

The second trajectory will have the same dimensions as thefirst. Do not start your second sketch exactly on top of thefirst; instead, allow the final modification of the dimensions tocause them to coincide in the sketching view. To complete thesketch, you may want to refer to the default view.


17. Do not define another trajectory. Click Done.

18. Specify the attributes. Click Open Ends >Done.

Task 3. Sketch the cross section.

1. Define additional references select the edges, as shown in thefollowing figure.


NOTES

Select these edges

Figure 6

2. Define the section. Sketch a horizontal line above the two Sketcherpoints 68.00 from A_1. Align the ends to the faces of the disk.

Figure 7


NOTES

3. While in Sketcher, add Sketcher relations. Click Sketch >Relation > Add, then type the following:

rbase = 64.0

todeg = 180/pi

unwind = 0

solve

unwind * todeg - atan(unwind) = trajpar*14.0

for unwind

sd# = rbase * (1 + unwind^2)^.5

(Where SD# is the symbolic value of the 68.00 dimension)

4. Finish entering the relations; click .

5. When you have finished, click . The system snaps the SD# tothe base circle radius 64.0.

Figure 8: Sketch after Adding Relation

6. Click OK to finish creating the surface.


NOTES


Figure 9

Task 4. Create a mirror copy of the involute surface.

1. Click Insert > Surface Operation > Transform > Mirror > Copy> Done.

2. To specify the surface to mirror, select the involute surface, andthen click Done Sel.

3. To specify the mirror plane, select DTM1.

Figure 10


NOTES

Task 5. Create a Thru All extruded solid cut. Use the new surfaces todefine the cross section in Sketcher using Use Edge.

1. Create the solid cut. Click Insert > Cut > Extrude > One Side >Done.

2. To specify the sketching plane, select the front of the part as thesketching plane. If necessary, flip the feature creation arrow topoint it to the other side of the part. Click Okay.

3. To specify the reference plane, click Top and select DTM1.

4. To specify the Sketcher references, select the DTM1 and RIGHTdatum planes. Select the involute surfaces as additional references.

5. Sketch the section for the cut as shown in the following figure.Sketch an arc at a 67.0 radius between the two involute surfaces.Use the Use Edge option on the boundary of both involutesurfaces.

Figure 11

6. Click to finish the sketch creation.

7. Specify the material to be removed. Using Flip, adjust the arrowdirection, as shown in the following figure, and then click Okay.


NOTES

Figure 12

8. Define the depth and finish the feature creation; click Thru All >Done > OK.

9. Review the changes in the default view.

Figure 13

Task 6. Round the edges of the new cut.

1. Create a single simple round. Select Insert > Round > Simple >Done > Constant > Edge Chain > Done.

2. Specify the edges to round. Retain the default Tangnt Chain.Select the edges, as shown in the following figure. Click Done.


NOTES

Select these edges

Figure 14

3. Type [1.0] as the radius value, and then click .

4. Click OK to finish the round creation.

Figure 15

5. Change the angle of DTM1. Click Modify and select DTM1. Selectthe specified dimension. Type [5] as the angle from TOP, and then

click .

6. Regenerate the feature.


NOTES

Figure 16

Task 7. Create a local group of the two involute surfaces: the cut, andthe round features.

1. Specify the local group for the involute surface. Click Feature >Group > Create > Local Group.

2. To specify a name for the local group, type [involute], and then

click .

3. Specify the geometry to include in the local group. Select all of thefeatures that you added to the initial part, including DTM1 throughto the round. Click Done Sel > Done.

4. Pattern the group. Click Pattern > Select > Sel By Menu. In theSELECTION TOOLS dialog box, locate and select Involute, andthen click Select.

5. Specify the dimension to pattern. Increment the angle of DTM1and select the 5.0-degree dimension:

6. To specify the increment, type [20], and then click > Done.

7. To specify the number of instance, type [5], and then click >Done.


NOTES

Figure 17

8. Exit the GROUP menu. Click Done/Return and Done.

Task 8. Blank the layers to hide the surfaces and the datum planes.

1. Blank LAYER 1.

Figure 18: Gear Teeth

2. Save the part and erase it from memory.


NOTES

EXERCISE 2: Creating a Helical CutGoal

In this exercise you create a helical cut around a torus.

Method

In this exercise you use create a helical surface using variable sectionsweep and relations; use this surface as a reference to create a helical cutaround a torus.

Task 1. Create a new part then create a datum curve.

1. Create a new part called TORUS.

2. Sketch a circular datum curve on TOP with a diameter of 20.00.

Figure 19

3. Sketch a second circular datum curve on TOP, concentric to thefirst, with a diameter of 23.50.


NOTES

Figure 20

4. Create a datum point. Using Curve X Srf, create a datum pointwhere the larger circular curve and FRONT cross, as shown in thefollowing figure.

Figure 21

Task 2. Create a solid protrusion.

1. To create a solid protrusion, click Insert > Protrusion > Sweep >Select Traj > Curve Chain. Select the inner circular curve, andthen click Select All. Check that the start point is adjacent to thedatum point as shown in the following figure. Click Done > NoInn Fcs > Done.


NOTES

Start Point

Figure 22

2. Sketch the section as a circle. Use the datum point to align theouter edge of the circle. You should not need to dimension it.

Figure 23


NOTES

Task 3. Create a surface.

1. Create a surface using Variable Section Sweep and Nrm ToOrigin Traj. Select the entire inner datum curve as the origintrajectory and the larger circular curve as the x-vector.

Origin Trajectory

X-Trajectory

Figure 24

2. Begin the section by sketching a construction circle with the centerpoint of the circle on the origin trajectory and the radius of thecircle on the x-vector. Sketch a single line and dimension, asshown in the following figure. You do not need to align it.

Figure 25

3. Write a relation to drive the angle as the system is sweeping thesurface, so that the surface makes eight revolutions [sd# =trajpar * 360 * 8]. Delete the reference circle beforefinishing the sketch.


NOTES

Figure 26

Task 4. Create a solid cut.

1. Create a solid cut using the Sweep and Select Traj options.Specify the trajectory. Click Tangnt Chain. Select the visible,yellow edge of the spiral surface, then click Done.

Figure 27

2. Accept the default direction for the upward horizontal plane of thesweep. Sketch the section with a diameter of 1.75, as shown in thefollowing figure. Remove the material from the center of the circle.


NOTES

Figure 28


4. Blank the default curve and surface layers to view the solid cut.

Figure 29: Finished Part

5. Save the part and erase it from memory.


NOTES

EXERCISE 3: Creating Difficult RoundsGoal

In this exercise you create a complex round along the non-tangential

edges of a solid using surface features.

Method

In this exercise, you create a round on the chain of edges in a part, asshown in the following figure. You use rounds to create a constant radiusalong most of the edge. Then, you use a different method to create asmooth, close approximation to a radius in the regions where a true radiusis mathematically impossible.

Upper chain ofedges

Lower chainof edges

Troublesome area

Figure 30: Original Geometry before adding the Round Feature

Task 1. Retrieve the model and create a simple round along the edges.

1. Open SURF_ROUND.PRT.

2. Click Insert > Round > Simple > Done > Constant > EdgeChain > Done.

3. Retain the default Tangnt Chain. Select the two edges, as shownin the following figure, and then click Done.


NOTES

Select these twoedges to round

Figure 31

4. Type [5.0] as the radius, and then click .

5. Click OK to finish creating the round.

Task 2. You have created the rounds; however, the shape is not as cleanas it could be. Investigate the problematic area.

1. Change the view to investigate the problematic area. Click > 1.

2. Note the area where the two rounds merge. This is the problematicarea that you are going to fix.

Figure 32: The Undesirable Portion of the Round



NOTES

Task 3. Redefine the round to make it an advanced round. Modify thefirst round set, and create a second round set that includes the bottom edgechain.

1. Click Redefine and select the round that you just created. Fromthe dialog box, click Round Type > Define > Advanced > Done.

Note:

After you change a round type to Advanced, you cannotreturn it to a simple round.

2. Click Round Sets > Define from the dialog box to break theselected references into two round sets.

3. Redefine the first round set to remove the lower chain of edges.Retain the default Redefine, and then click Rnd Set 1.

4. Click References > Define from the ROUND SET 1 dialog box.

5. Click Unselect and select only the lower chain of edges, then clickDone Sel.

6. Click Done > OK to finish the first round set and.

7. Click Add to add a second round set to include the lower chain ofedges.

8. Retain the defaults Constant and Edge Chain, and then clickDone.

9. Click Tangnt Chain, select the lower chain of edges again, andthen click Done.

10. Type [5.0] as the radius, and then click .

11. Click OK from the dialog box.

12. Click Done Sets to finish redefining the round sets. Do not closethe dialog box.


NOTES

Task 4. Create a surface instead of a solid feature to clean up thetransition area between the two sets.

1. Change both the attachment type and transition between the sets toa surface. Press <CTRL>, click Transitions and Attach Type fromthe dialog box, then click Define.

2. Create stop transitions for both round sets. Click Add by Type >Stop >Done.

3. Select one of the green ends of the two round sets where they meet,as shown in the following figure, and then click Done.

4. Select the other green end, and then click Done > Done Trans.

Specify these twogreen edges

Figure 33

5. Click Make Surface > Done to create a surface instead of a solid.

6. Click OK to finish redefining the round. The model should displayas shown in the following figure.

Figure 34


NOTES

Task 5. Trim the surface back to the region of focus using the existingedges of the round surfaces, as well as constructed datum curves or datumplanes.

1. Change the view to zoom in on the problematic area. Click > 1.If necessary, you may want to zoom in further.

2. Create a datum plane to use to trim the existing surface. ClickInsert > Datum > Plane > Through. Select the left endpoint of thelower chain of edges as shown in the following figure.

3. Click Normal. Select the lower edge, as shown in the followingfigure, and then click Done.

Make a datumplane through the

left endpoint ofthis lower edge

Make the datum plane andnormal to this edge

Figure 35: Problematic Area

4. Click > Default to zoom-out and determine if the datum planeintersects the upper part of the round surface.

5. Note that the datum plane does not intersect any other surfacefeature or quilt, therefore, you can use it to trim the surface.

Task 6. Since you need to concentrate on the small area, redefine thedatum plane to fit the edge.

1. Click Feature > Redefine and select the datum plane that you justcreated.

2. Click Attributes > Done > Fit Edge > Done.

3. Zoom in and select the same edge that you used for the normalconstraint to define the outline of the plane.


NOTES

Task 7. Trim the lower round set to remove the unwanted material.

1. Click Insert > Surface Trim > Use Quilt.

Specify this quiltto cut using thedatum plane

Figure 36

2. Select the lower set of round surfaces to specify the quilt tointersect.

3. Select the datum plane that you just created.

4. Specify the side to retain. Click Side 1 > Done.

Figure 37

5. Click OK to finish trimming the quilt.

Task 8. Create a datum plane as the trimming plane for the upper roundset.

1. Click > 1 to zoom in.


NOTES

2. Create a datum point on the upper edge chain to locate the datumplane. Click Insert > Datum > Point > On Curve > Length Ratio.Select the edge, as shown in the following figure, and then clickDone Sel.

Select this location forthe datum point

Figure 38

3. Type [0.25] as the curve length ratio, and then click .

4. Click Done to complete the point.

5. Create a datum plane. Click Insert > Datum > Plane > Through.

6. Select the datum point that you created previously.

7. Click Normal and select the edge, as shown in the followingfigure. Click Done.

Make a datumthrough the datumpoint and normal tothis edge

Figure 39

8. Redefine the datum plane to fit the edge. Click Feature >Redefine and select the datum plane that you just created.

9. Click Attributes > Done > Fit Edge > Done.


NOTES

10. Zoom in and select the same edge that you used for the normalconstraint to define the outline of the plane.

Figure 40

Task 9. Trim the upper round set using the datum plane to remove theunwanted material.

1. Click Insert > Surface Trim > Use Quilt.

Quilt to be trimmed

Figure 41

2. Select the upper set of round surfaces to specify the quilt tointersect.

3. Select the datum plane that you just created.

4. Specify the side to retain. Click Side 2 > Done.


NOTES

Figure 42

5. Click OK to finish trimming the quilt. The model should appear asshown in the following figure.

Figure 43: Model after Trimming

Task 10. In order to create a blended surface, create the first boundarycurve joining the edges of the two trimmed round sets. Create a projectedcurve that lies on the solid surface and is tangent to the edges.


2. Create a projected datum curve. Click Insert > Datum > Curve >Projected > Done > Sketch > Done.

3. Select DTM2 as the sketching plane.


5. Click Bottom and select DTM3 as the reference plane.

6. Assign additional references. Zoom in on the problematic area andselect the two edges of the round set, as shown in the followingfigure.


NOTES

7. Sketch a spline with tangent ends, using the end points to connectthe two surface patches, as shown in the following figure.

Select theseedges as theadditionalreference

Figure 44

8. Add tangency constraint to make the curve tangent to the edges.

Figure 45


10. Change the view. Click > 1.

11. Specify the surface for projection. Retain the defaults Surface,Include, and Indiv Surf. Select the large round surface, as shownin the following figure.

Surface ontowhich to project

the spline

Figure 46

12. Click Done Sel > Done > Norm to Sket > Done.


NOTES

Note:

The second option, Norm to Surf, projects the sketch normalto the selected surface.

13. Click OK to finish creating the projected datum curve.

Projected Curve

Figure 47

Task 11. Create another curve to define the second boundary of theblended surface. Create a projected curve that lies on the solid surfacesand that is tangent to the edges of the round set surfaces.

1. Click Insert > Datum > Curve > Projected > Done > Sketch,and Done.

2. Select DTM3 as the sketching plane.


4. Click Top and select DTM2 as the reference plane.

5. Define the additional Sketcher references. Select two edges, asshown in the following figure.

Select thesetwo edges asadditionalreference

Figure 48


NOTES

6. Sketch a spline that is tangential to the two edges that you selectedas the Sketcher reference, as shown in the following figure.

Constrain thespline as tangentto both the ends

Figure 49


8. Specify the surfaces for projection. Retain the defaults Surface,Include, and Indiv Surf. Select the two solid surfaces, as shown inthe following figure.

Surfaces toproject the spline

Figure 50

9. Click Done Sel > Done Norm to Sket > Done.

10. Click OK to finish the curve creation.


NOTES

Figure 51

Task 12. Create a boundary surface using the curves that you created andthe edges of the round sets.


2. Define the first direction curves. Retain the defaults First Dir, AddItem, and Curve. Select the two projected datum curves then clickDone Sel.

3. Define the second direction curves. Click Second Dir. Retain thedefault Add Item, then click Chain > One By One > Select.

Tips & Techniques:

It is always good practice to use the edge of the adjacentsurface instead of that surface’s defining curves.

4. Define the first curve. Select the edge of the first round set asshown in the following figure, then click Done Sel > Done.

Select theseedges

Figure 52


NOTES

5. Define the second curve. Click One By One, select the edge of theother round set, as shown in the preceding figure. Click Done Sel> Done.

6. Click Done Curves to finish selecting the boundary curves.

Task 13. Define the boundary conditions of the surface to make it tangentto the adjoining surfaces.

1. In SURFACE: BLENDED dialog box, click Bndry Conds >Define from the dialog box.

2. Identify the first correct boundary. Move the mouse cursor over theboundary list until one of the shorter edges of the round set ishighlighted.

3. Click Boundary # > Tangent > Done > OK.

4. Move the mouse cursor over the boundary list until the next shorteredges of the round set are highlighted. Click Boundary # >Tangent > Done > OK.

5. Identify the third correct boundary. Move the mouse cursor overthe boundary list until the upper larger curve is highlighted, asshown in the following figure.

6. Click Boundary # > Tangent > Done > OK.

7. Click Done to finish defining the boundary conditions.

8. Click OK to finish creating the blended surface.

This edge shouldbe tangent to thelarge roundsurface

Figure 53


NOTES

Task 14. Merge the round set surfaces and the blended surface that youhave created.

1. Click Insert > Surface Operation > Merge > Join. Select one ofthe round surfaces, then select the blended surface.

2. Continue to join the surfaces. Click and select the other roundset of surfaces.

3. Click to finish merging the surfaces.

Task 15. Create a patch for the single merged quilt.

1. Click Insert > Advanced > Patch. Select the merged quilt.

2. Specify the arrow direction towards the resulting solid, as shown inthe following figure, and then click Okay.

Figure 54

3. Observe the model. Notice the improved round around theproblematic area.


NOTES

Figure 55: The Improved Round


Page B-1

Appendix

Using PTC HelpYou can use PTC Help to quickly search for Pro/ENGINEER

information. PTC Help includes quick references and detailed

information on selected topics.

Objectives


• Start PTC Help.

• Search for specific information about Pro/ENGINEER.

• Obtain context-sensitive help while performing a task.

Page B-2 Append ix B

NOTES

PTC HELP OVERVIEWPTC Help is a fully functional help system that is integrated intoPro/ENGINEER.

PTC Help FeaturesPTC Help offers:

• A new help system with a table of contents, an index, and searchingcapability

• Context-sensitive help, allowing access to PTC Help with a click ofthe mouse

• Online Tutorials focussed on teaching different aspects of the software

• Expanded help topics available as special dialog boxes

Please visit the PTC Technical Support Online Knowledge Database,which features thousands of Suggested Techniques. For moreinformation, see the Technical Support Appendix.

USING THE Pro/ENGINEER HELP SYSTEM

Launching Help: Four MethodsThere are four procedures for launching the help system.

1. From the Main Menu

This is the standard way of accessing the full-blown help system completewith contents, index, and search capabilities. Depending on your systemspeed, it may take a few seconds to launch the entire help system.

Click Help > Contents and Index from the main menu as shown in thefollowing figure.

Using PTC Help Page B-3

NOTES

Figure 1 Starting PTC Help

The Pro/ENGINEER Online Help homepage appears in your web browserwindow.

Figure 2: Contents and Index in PTC Help

In the left frame of the window, you see a list of topics arranged in a treestructure. By clicking on each higher level topic, you can access sub-topics, and by clicking the sub-topics you can access detailed instructions,explanations, and tips.


NOTES

2. Through Context-Sensitive Help

1. Click on the right end of the main toolbar.

2. Click on any icon or any part of the Pro/ENGINEER main windowabout which you want an explanation.

3. A browser window opens that explains the topic.

4. In the following example, clicking on the model tree icon in thetoolbar launched a browser window that explained the iconfunctionality.

Figure 3: Context-Sensitive Help

5. In addition, you will also notice at the lower left there is a “SeeAlso” link which on clicking provides a list of related topics thatmay be of immediate interest.


NOTES

6. You may click on any topic you want to read additionally.

Figure 4: The ‘See Also’ List of Topics

3. Through Pro/ENGINEER Menu Manager

1. Click on the right end of the main Pro/ENGINEER toolbar.

2. Click any menu command from the menu manager.

3. A TOPIC ROUTER browser window opens with a list of topic linksthat explain the menu command.

4. Click the topic you want to read.

5. In the following example, clicking on X-Section in the menumanager launched the TOPIC ROUTER browser window with a listof two useful topics.


NOTES

Figure 5: Launching Help through Menu Manager

4. By Right-Clicking on Vertical Menu Commands

1. Right-click and hold on a menu command until the GETHELPwindow appears.

Figure 6: Right-Clicking in Menu Manager


NOTES

PTC HELP MODULE LISTThere are four main branches in the PTC Help table of contents:Welcome, Pro/ENGINEER Foundation, Using Foundation Modules, andUsing Additional Modules.

Figure 7: Four Main Branches in Help System

Consult the following list to find a particular module in the table ofcontents:

Figure 8: Foundation and Additional Modules in Help

Documents

Designing With Surfaces 2001