design basics with cad

iv

Autodesk Education Curriculum

Introduction

The word design is used throughout many disciplines, each with its own slightly different definition.Technical and nontechnical people alike use the word in its generic form to identify something that isthe product of a conscious human effort.

Design as a process is the cornerstone of all engineering professions. Professionals often use theterm design process when talking about a method by which problems are identified and solutions aregenerated. This sometimes suggests there is only one way to plan or problem-solve. In fact, there area multitude of methods to design. Some are vague, while others are quite detailed. But they all startwith a need, a problem, or a want, and follow through a series of steps or phases that result in thecreation of something that serves as a solution to the need, problem, or want.

1

Autodesk® Design Academy

Unit 1 - Design Overview

Standards for Technological Literacy■ Defining a problem■ Brainstorming■ Researching and generating ideas■ Identifying criteria and specifying constraints■ Exploring possibilities■ Selecting an approach■ Developing a design proposal■ Making a model or prototype■ Testing and evaluating the design using specifications■ Refining the design■ Creating or manufacturing it■ Communicating processes and results

After completing this unit, you will be able to:

■ Redesign a product.■ Describe the evolution of a product.■ Review the design process.■ Create isometric, oblique, perspective, and multiview sketches of mechanical objects.

2 ■ Autodesk Design Academy Unit 1 - Design Overview

Initial design sketches of a watch

Lessons■ Introduction to the Design Process■ Introduction to Technical Sketching

The Engineer's Notebook ■ 3

The Engineer's Notebook

Students are expected to start an engineer’s notebook at the beginning of a course. This notebookwill be used throughout the year to chronologically document class notes, sketches of project ideas,journal entries, calculations, photographs, and other critical information. In addition to the engineer’snotebook, students should keep a dedicated three-ring binder for class handouts. You are free to use avariety of methods to have students keep an engineer’s notebook.

If you want to follow engineering practices as expected in college programs, it is recommended thatyou visit, print, and read the engineering notebook guidelines found at BookFactory: EngineeringNotebook Guidelines. (http://www.bookfactory.com/special_info/engrnotebook_guidlines.html)

The content in this lesson is derived from the course Introduction to Engineering Design developedand copywritten by Project Lead the Way, Inc.

What is an Engineer's Notebook?

The engineer’s notebook, as kept by a professional engineer, is a bound text with quadrille-ruledpages. Loose leaf writing paper is acceptable, provided it is well maintained and students understand aproper engineering notebook is bound. They will be required to keep a bound engineer’s notebook inlater classes. You may want to have a notebook as an example. It is recommended that the notebookhave prenumbered pages, with designated locations for the dated signatures of the designer andwitness.

Other types of lower cost, bound, quadrille-ruled notebooks are available at most office supply stores,but they generally do not have prenumbered pages or designated locations for the dated signatures ofthe designer and witness. It would be the student’s responsibility to individually write this informationin ink on the front and back of each page before beginning an entry.

Sample Engineer's Notebook Entries

The following would be considered excellent examples of entries in an engineer’s notebook.





The following list provides reasons why the examples represent an excellent engineer’s notebook:

■ The pages have been numbered sequentially.■ The pages are part of a bound notebook.■ There is a dedicated location on each page for the designer’s and witness’s dated signatures.■ All figures and calculations have been clearly labeled.■ Inserted items have been properly attached to their respective pages.■ The student included annotated sketches that help the reader understand the ideas.■ Detailed explanations of how the designs are supposed to work were given.■ The student gave evidence of research.■ Problems that were encountered through experimentation were chronicled, and ideas to fix them

were clearly evident.■ A technical drawing for a prototype was given, which specified the material from which the part

was to be made.■ Included was a digital photograph of the prototype that suggests how the object is to be

assembled.■ The date for each entry is clearly identified.■ The information given in the entries is proportional to the amount of time given per class period.■ Any mistakes that were made had a single line drawn through them, and were initialed.


The following is an example of an unacceptable engineer’s notebook. Keep in mind that each entryrepresents a reflection of 75 minutes of continuous work.


The following list provides reasons why the examples are unacceptable for an engineer’s notebook:

■ The student submitted a sheet of loose-leaf paper that was removed from a wire bound spiral

notebook. An engineer’s notebook must be a bound document. No pages should ever be removedfrom an engineer’s notebook.

■ The page number is not identified in ink.■ The student did not sign and date the page.■ There were several class days between 9/22 and 10/11 that are not represented by notebook

entries.■ There were no sketches, CAD model graphics, or technical drawings to support the idea that the

support bar, guide, or displacement arm was actually designed or being built. It also appeared thatthe student was leaving room so that he/she could go back and add sketches later on in an attemptto satisfy the rubric.

■ Except for wood, which encompasses a broad spectrum, no tools or materials were identified asbeing used.

■ The student offered no explanation as to functions of the support bar, wood guide, anddisplacement arm.

■ The entries do not show that the partners talked about their ideas or worked on their designs as ateam.

■ Only fragments of ideas have been documented. There is no detail at all.■ The student used inappropriate expletives in a formal document, and was openly disrespectful to

his/her teammate.■ 75 minutes of work cannot be accurately and completely summed up in one sentence.■ The entries do not talk about any special considerations or problems that might have been

encountered during the design of the parts.

Detailed Overview

Review the Engineer's Notebook.ppt file. It is located in the Instructor Resources folder.


Introduction to the Design Process

Cars, MP3 players, cell phones, clothes, and video games are just a few products that are familiar tomost people. What is it about any of these products that you like? What causes you to want to buy anMP3 player or a cell phone? Is it the commercials or is it the appearance of the product? Whateverthe reason, design plays a vital role in the creation and marketing of any product.

Key Terms

assessment design process invention sequential

brainstorming designer iterative solution

client engineer problemidentification

standard

constraint engineer'snotebook

process target consumer

design evolution product timeline chart

design brief innovation research

Standards

Autodesk® Design Academy curriculum meets content standards for Science, Technology, Engineering,Math (STEM), and Language Arts. To review the list of standards for each lesson, view the NationalAcademic Standards Cross Reference PDF document.

This lesson relates to science, technology, engineering, and math standards.

Introduction to the Design Process ■ 11

Lesson Plan - Introduction to the Design Process

Time: 11 days

1. TEACHER: Present Key Terms.2. TEACHER: Present Engineers.ppt.3. TEACHER: Distribute an engineer's notebook or have the students create their own.4. TEACHER: Distribute Sample Engineer's Notebook Entries to each student and review typical

entries.5. TEACHER: Present Engineers Notebook.ppt.6. TEACHER: Distribute and introduce the exercise Redesign a Product.7. TEACHER: Present Rules for Brainstorming.ppt.8. STUDENTS: Complete Exercise: Redesign a Product.9. STUDENTS: Present product redesign ideas to the class.10. TEACHER: Present Evolution of Product Design.ppt.11. TEACHER: Distribute and introduce the exercise Product Evolution.12. TEACHER: Distribute and introduce the exercise Product Evolution Rubric.13. STUDENTS: Complete Exercise: Product Evolution.14. STUDENTS: Present their PowerPoint on product evolution to the class.15. TEACHER: Distribute and introduce the exercise Review the Design Process.16. TEACHER: Present Design Process Overview.ppt.


Exercise: Redesign a Product This exercise is designed to provide an introductionto design. As a team of two, you brainstorm ways toenhance or change a plain white beverage containerso that nearly every consumer wants to purchase it. The content in this exercise is derived from the courseIntroduction to Engineering Design developed andcopywritten by Project Lead the Way, Inc. Supplies Supplies for this exercise include:■ Paper■ Plain white coffee cup (1 per class)■ Pencil

Redesign a Product 1. Review the rules for brainstorming that were

identified in the PowerPoint presentationbefore you started this exercise.

2. Form teams of two. 3. Assign a recorder and a speaker for your group. 4. Brainstorm for five minutes with your team to

identify enhancements or changes that youwould make to the item.

5. The recorder writes down all ideas

mentioned in those five minutes. (Changes orenhancements could be anything; you are notlimited by cost.)

6. After five minutes, select from the

brainstorming list, the ideas to enhance orchange the item.

7. Your team takes another five minutes to

develop and sketch the changes. 8. The speaker from each team presents their

ideas to the class.


Exercise: Product Evolution People are surrounded by everyday products, such asthe automobile, that have gone through seeminglycountless iterations of a design process. Any objectthat is constantly redesigned is experiencing theprocess of innovation. It is through innovation thata product evolves. As most products evolve, it isassumed they become better. Sometimes this istrue, and sometimes it is not. Close examinationof the history, purpose, and evolution of a productwill greatly enhance your understanding of productdesign. What is the difference between an inventor andan innovator? If you have ever heard the phrase“reinventing the wheel,” then you probably know theanswer. The person who created the first wheel wouldbe the inventor. The person who modified the wheelto be made out of aluminum alloy that is covered by asynthetic rubber tire would be an innovator. The content in this exercise is derived from the courseIntroduction to Engineering Design developed andcopywritten by Project Lead the Way, Inc.

Product Evolution In this exercise, you analyze the evolution of aproduct and trace it from its beginning to its currentuse or end. 1. Individually, select a product from your hobby

or interest that has undergone noticeableimprovements over some time period. Theproduct that you select must be preapprovedby your instructor.

2.

Review Product Evolution Rubric.pdf. Yourinstructor will distribute a hard copy of this file.

3. Use the Internet, books, and other reference

materials to search for information on theevolution of the product you have selected.

4. To assist you with your research, focus on the

following information:■ When was the product invented?■ Who invented the product?■ What materials were originally used to

make the product?■ How was the product originally made?■ What improvements have been made to

the product over the years?■ Why were these improvements made?■ Who uses the product?

5. Save information and graphics to your student

network folder to be used in the developmentof a PowerPoint presentation.


6. Make sure you record and properly reference

all information sources in your engineer’snotebook.

7. Develop a three-to-five minute PowerPoint

presentation that includes the followinginformation:■ Title slide with your name, class, period,

and selected product.■ Explanation of the product.■ A timeline showing the history of the

product.■ Major changes that have occurred in the

design of the product.■ Effects on society and the environment.■ A reference page of at least four Internet

sites and other sources used to gather yourpresentation information, recorded in APAstyle.

8. Present your findings to the class.


Exercise: Review the Design Process What would you do if you had a teacher whoexpected you to complete an assignment, but refusedto tell you what the assignment was? Imagine, too,that the result of this assignment was expected tobe submitted in a specific format, which was alsonot explained to you. Oh yes, and there was a duedate. But you were not told what that was either. Howcould a person be expected to accomplish anythingunder such conditions? design brief The content in this exercise is derived from the courseIntroduction to Engineering Design developed andcopywritten by Project Lead the Way, Inc. Supplies Supplies for this exercise include:■ The Flight of the Gossamer Condor DVD■ Television or computer with projector and audio

amplifier■ DVD player■ Pencil Note: The DVD can be purchased on-line. It may alsobe available at your local library or school resourcecenter.

Review the Design Process In this exercise, you witness the development ofthe first controlled, sustainable human-poweredaircraft as chronicled in the Academy Award-winningdocumentary, The Flight of the Gossamer Condor. 1. Imagine that you have traveled back to the

mid 1970's. You are part of a design teamthat is attempting to build a human-poweredaircraft. The project leader has given you theresponsibility of:■ Defining the problem.■ Stating the expectations that the solution

must meet.■ Identifying the project constraints. Your design brief will serve as a guide to theteam as they work through the design process.

2. From your observations of the film, answer

the following questions and record your

information in the design brief supplied by yourteacher.■ Who was responsible for the design of the

Gossamer Condor? Write your answer onthe line next to the word Designer in thedesign brief.

■ What was the problem that the designerand his team were trying to solve? Beadvised, the problem was not to design anaircraft. The design of an aircraft was partof the solution to the problem. Write youranswer as a complete sentence(s) on thelines next to the words Problem Statementin the design brief.

■ To what degree was the solution to berealized? Was the designer’s intention tomerely sketch an idea and be done? Wasthe intention to come up with an idea, buildit, and stop there? Or, was it the designer’sintention to design, build, and test an idea?

■ What expectation(s) did the design haveto meet before it would be considered asuccessful solution to the problem? In otherwords, what did the solution have to do?Combine your answer with the answer fromquestion three, and write it as a completesentence(s) on the lines next to the wordsDesign Statement in the design brief.

■ What limitations did the design team haveto work with?

■ What criteria did the solution have tomeet?


Introduction to Technical Sketching

It is often said that a picture is worth a thousand words. This proverb is very true whencommunicating ideas to solve problems. To properly communicate technical information aboutobjects that must be manufactured, fluency in the universal language of technical drawing is required.One of the first steps to learning this language is developing the ability to sketch.

Visualizing, communicating, exploring, and documenting ideas occur throughout the process ofdesign. The process begins when a client and an engineer meet for the first time to define a problem;when research requires field measurements to be taken so that a scenario can be replicated; whenan idea occurs during lunch and must be quickly recorded on a napkin before it is lost; when teams ofpeople feed off each others's ideas and brainstorm possible solutions; when an engineer works outthe details of a design solution so that it can be prototyped and tested; and when a solution has beenproven to work and must be documented for reproduction.

Technical sketching differs from technical drawing: technical sketches are made with a pencil, paper,and an idea, while technical drawing advances a sketch to follow specific technical drawing guidelinesthat employ the use of tools, such as isometric graph paper and a computer. Likewise, technicalsketching differs from artistic sketching. Technical sketches follow the same standards that govern thedevelopment of technical drawings except the sketches are done freehand.

As students advance in their experiences and skills through the course, they learn basic rules oftechnical sketching in this lesson and will learn the drawing standards that apply. The understandingof technical sketching is critical for designers to effectively convey their ideas about a product.Sketching is the beginning stages of product development. Students will learn how to sketchisometric, oblique, perspective, and multiview sketches of various objects.

Introduction to Technical Sketching ■ 17

Key Terms

construction line line weight projection line views

depth manufacture projection plane visualize

documentation measurement proportion width

edge multiviewdrawings

scale

ellipse object line shading

freehand oblique sketch shape

grid orthographicprojection

size

height perspectivesketch

sketch

hidden line pictorial sketch solid

isometric sketch plane technical workingdrawing

line point tone

line conventions profile vanishing point

Standards


This lesson relates to technology, engineering, and math standards.


Lesson Plan - Introduction to Technical Sketching

Time: 11 days

1. TEACHER: Present Key Terms.2. TEACHER: Present Line Conventions.ppt.3. TEACHER: Present Isometric Pictorials.ppt.4. TEACHER: Distribute Isometric Graph Paper.5. TEACHER: Distribute and introduce the exercise Create Isometric Sketches.6. STUDENTS: Complete Exercise: Create Isometric Sketches.7. TEACHER: Assess the exercise using the Create Isometric Sketches Answer Key.8. TEACHER: Present Oblique Pictorials.ppt.9. TEACHER: Distribute and introduce the exercise Create Oblique Sketches.10. STUDENTS: Complete Exercise: Create Oblique Sketches.11. TEACHER: Assess the exercise using the Create Oblique Sketches Answer Key.12. TEACHER: Present Perspective Sketches.ppt.13. TEACHER: Distribute and introduce the exercise Create Perspective Sketches.14. STUDENTS: Complete Exercise: Create Perspective Sketches.15. TEACHER: Assess the exercise using the Create Perspective Sketches Answer Key.16. TEACHER: Present Multiview Sketching.ppt.17. TEACHER: Distribute and introduce the exercise Create Multiview Sketches.18. TEACHER: Review the use of hidden lines and centerlines in technical sketches.19. STUDENTS: Complete Exercise: Create Multiview Sketches.20. TEACHER: Assess the exercise using the Create Multiview Sketches Answer Key.


Exercise: Create Isometric Sketches How do reading the face of a clock and sketchingisometric pictorials relate to each other? Picture acube in your mind. All of the surfaces of the cubeform right angles with their adjacent faces. If youwere to draw an isometric pictorial of the cube,you would see that the edges point toward 2 and 8o’clock, 4 and 10 o’clock, and 6 and 12 o’clock. Thisidea helps when sketching isometric pictorials onwriting surfaces that do not have isometric grids. Isometrics are very common in computer-aideddesign (CAD) programs and are only slightly moredifficult to sketch than oblique pictorials. The content in this exercise is derived from the courseIntroduction to Engineering Design developed andcopywritten by Project Lead the Way, Inc. Supplies Supplies for this exercise include:■ Engineer's notebook■ Number 2 pencil■ Various objects

Create Isometric Sketches PDF In this exercise, you develop isometric sketching skillsby drawing views of objects that are already given inan isometric orientation. You will apply your sketchingskills throughout the remainder of the course. 1.

Review Create Isometric Sketches.pdf. Yourinstructor will distribute a hard copy of this fileand isometric graph paper.

2. Complete all the steps listed in the exercise.


Exercise: Create Oblique Sketches Have you ever tried to explain to another personwhat an object looks like using words and handgestures? The technique does not work very well,especially if the person does not understand thevocabulary you use. In the engineering world,it is often the case that an idea needs to becommunicated and explained quickly. Questions, suchas what does the idea look like? or how will it work?need to be answered. In most cases, words andhand gestures alone cannot answer these questions.Sketching ideas is a quick and efficient method thatis used in all fields of engineering to get ideas downbefore they are lost. If the idea turns out to be apossible solution, the sketch will serve as the basis formore advanced drawings and conveying ideas such ascomputer-aided design (CAD) solid-modeling. The content in this exercise is derived from the courseIntroduction to Engineering Design developed andcopywritten by Project Lead the Way, Inc. Supplies Supplies for this exercise include:■ Engineer's notebook■ Number 2 pencil■ Various objects

Create Oblique Sketches In this exercise, you practice sketching and technicalcommunication skills by creating general obliquesketches of objects on graph paper. A general obliquesketch has lines that can be drawn at any scale andany angle. The most common angles are 30, 45, and60 degrees, but any angle can be used. 1.

Review Create Oblique Sketches.pdf. Yourinstructor will distribute a hard copy of this file.



Exercise: Create Perspective Sketches If you can stand on a straight road and look down theroad, the sides of the road begin to look as if they arenarrowing to one point and the center of the roadvanishes when the road meets the horizon. If theroad is straight enough and long enough, the sides ofthe road not only look like they are converging to asingle point, but the road seems to appear to vanishas it meets the horizon. A similar effect happens ifyou stare upward from the base of a tall building. Thevertical edges of the building will appear to angle intoward each other. This effect is called perspective. The human eye sees the world in perspective. Objectsthat are further away from the eye appear smaller,and edges appear to recede into the distance.Perspective sketches depict objects in much the sameway that the human eye sees the world. There are three different types of perspectivedrawings: one-point, two-point, and three-pointperspective. The different types of sketches arefrequently used by architects, industrial designers,and illustrators when representing large-scale objectsor environments in which the effect of distance mustbe taken into consideration. The content in this exercise is derived from the courseIntroduction to Engineering Design developed andcopywritten by Project Lead the Way, Inc. Supplies Supplies for this exercise include:■ Engineer's notebook■ Number 2 pencil■ Various objects

Create Perspective Sketches In this exercise, you practice sketching skills bygenerating a one-point, two-point, and three-pointperspective of a given object. You then apply yourskills by creating either a one-point, two-point, orthree-point perspective of an object you select. 1.

Review Create Perspective Sketches.pdf. Yourinstructor will distribute a hard copy of this file.



Exercise: Create Multiview Sketches It is a very common occurrence to see a productadvertisement and think, I thought of an idea forsomething like that just a few months ago. Peoplespend a lot of time in their various interest areas andenvision ideas for making things work better. Spendsome time with someone who has a permanentdisability and see how many product ideas come tomind that would provide a degree of freedom to aperson who has lost a physical capability years ago.Coming up with wonderful ideas is only the first stepin developing solutions to problems. At some point,ideas must be built. You have practiced different techniques for sketchingobjects so that they appear to have a three-dimensional quality. These techniques are excellentfor quickly communicating ideas to both technicaland nontechnical people. Those who make their livingbuilding ideas require a different type of drawingformat. A multiview sketch, also referred to as anorthographic projection sketch, is the standard sketchformat used by engineers to communicate ideas toprofessionals in the building trades. However, pictorials do not provide accurateinformation about the true size and shape of anobject and all of its features. It is often the casethat engineered objects have features and edgesthat are obscured by the standard surface views ofa multiview drawing. These views require hiddenlines. When engineers create drawings of cylindricalobjects, or objects that have holes, they mustrepresent their axes and axes points with centerlines. The content in this exercise is derived from the courseIntroduction to Engineering Design developed andcopywritten by Project Lead the Way, Inc. Supplies Supplies for this exercise include:■ Engineer's notebook■ Number 2 pencil

Create Multiview Sketches In this exercise, you develop your ability to visualizeand sketch objects as a series of related two-dimensional views. Understanding and using thedifferent line conventions, discussed earlier in thislesson, will help you when creating these views.

1.

Review Create Multiview Sketches.pdf. Yourinstructor will distribute a hard copy of this file.


Introduction ■ 23


Unit 2 - AutoCAD Basics

The Sketching and Annotation, Pre-Civil Engineering, and Pre-Architecture units use AutoCAD orAutoCAD based appplications. To ensure that you have the prerequisite basic skills to use theseapplications, a series of introductory exercises are provided. The objectives of the exercises are asfollows:■ Navigate the AutoCAD graphic environment, zooming and panning to view objects, using the

command window, the help system, and exploring environment settings and function keys.■ Configure fundamental drawing settings and options such as Scale, Grid, Snap, Object Snap, file

paths, and display colors.■ Create basic AutoCAD objects such as lines, polylines, circles, arcs, and polygons using menus,

palettes, keyboard commands, mouse controls, coordinates, and object snaps.■ Modify AutoCAD objects using multiple techniques including grip editing and object properties.■ User layers to control object settings.■ Navigate and view objects in 3D.■ Create reusable internal blocks and world blocks.■ Use externally referenced drawings in the current drawing.■ Draw objects in paper space (layouts) and configure one or more viewports in a layout.■ Create a properly formatted layout with required map elements such as a title block, north arrow,

border, and scale.■ Configure the page setup and plot layouts to an engineering scale.

AutoCAD Install and Basics

Installing AutoCAD

It is recommended that you install AutoCAD® Civil 3D® and use the Civil 3D as AutoCAD option. Thisprovides a basic AutoCAD environment.

AutoCAD Basics Learning Material

The AutoCAD Basics material is provided in PDF format. To view the content, open AutoCAD Basics.pdffrom the Printable Lessons folder.

24 ■ Autodesk Design Academy Unit 2 - AutoCAD Basics

Summary

This unit introduced you to the basics of AutoCAD. The interface was explained and drawing settingswere explored. New objects were created and modified. You navigated in three dimensions andcreated blocks and external references. Finally, you learned about layouts, viewports, and plottingissues. Completion of these exercises is critical to a good working knowledge of the AutoCAD Civil 3Denvironment.

Introduction ■ 25


Unit 3 - Sketching and Annotation

In this unit, you learn about measurement and statistics.

After completing this unit, you will be able to:

■ Research and design a CD cover or book jacket on the origins of the measurement systems.■ Measure and record linear distances using a scale to a precision of 1/16 inch and 1 mm.■ Measure and record linear distances using a dial caliper to a precision of 0.001 inch.■ Apply linear dimensions to a multiview drawing.■ Convert linear distance measurements from inches to millimeters and vice versa.■ Calculate the mean, mode, median, and range of a data set.■ Create a histogram of recorded measurements showing data elements or class intervals, and

frequency.

Dial caliper measuring depth

26 ■ Autodesk Design Academy Unit 3 - Sketching and Annotation

Normal distribution on a histogram

The practice of measuring is older than recorded history. Every human civilization throughout historydeveloped its own measuring tools and, along with them, its own measuring standards. It was throughthe establishment of measuring tools and standards that the Egyptians were able to build their giantpyramids, and the Romans were able to build their roads and aqueducts. Shared understanding andcommunication established through standardization played a key role in their successful outcome.Standardization is what allows many people to work individually on parts that come together to forma finished product or system. Without measurement standards, manufactured parts would not beinterchangeable and mass production could not exist. Measurement is so important that the foundingfathers of the United States included it in the Constitution, giving Congress the power to set uniformstandards for weights and measures. Today, the American National Standards Institute serves asthe unifying force system for the measurement used in the United States. This lesson provides anintroduction to measurement through the study of linear distance and angles.

Since the beginning, scientists have realized the laws of nature are not bound to the bordersbetween kingdoms or countries, and that uniform standards of measure form the foundation forchanging the secrets of the universe into human knowledge. In the midst of the French Revolution,scientists developed a new system of measurement that was simple, logical, and well-suited to theneeds of both scientists and engineers. Since its inception 220 years ago, the metric system hasspread throughout the industrialized world, and is now the international standard for acquiring andcommunicating measurements.

Lessons■ Measurement and Statistics■ Sketching Tools and Techniques

Measurement and Statistics ■ 27

Measurement and Statistics

The practice of measuring is older than recorded history. Every human civilization throughout historydeveloped its own measuring tools and, along with them, its own measuring standards. It was throughthe establishment of measuring tools and standards that the Egyptians were able to build their giantpyramids, and the Romans were able to build their roads and aqueducts. Shared understanding andcommunication established through standardization played a key role in their successful outcome.Standardization is what allows many people to work individually on parts that come together to forma finished product or system. Without measurement standards, manufactured parts would not beinterchangeable and mass production could not exist. Measurement is so important that the foundingfathers of the United States included it in the Constitution, giving Congress the power to set uniformstandards for weights and measures. Today, the American National Standards Institute serves asthe unifying force system for the measurement used in the United States. This lesson provides anintroduction to measurement through the study of linear distance and angles.

Since the beginning, scientists have realized the laws of nature are not bound to the bordersbetween kingdoms or countries, and that uniform standards of measure form the foundation forchanging the secrets of the universe into human knowledge. In the midst of the French Revolution,scientists developed a new system of measurement that was simple, logical, and well-suited to theneeds of both scientists and engineers. Since its inception 220 years ago, the metric system hasspread throughout the industrialized world, and is now the international standard for acquiring andcommunicating measurements.


Key Terms

ANSI/ASME Standards dimension lines metric system two-dimensional

accuracy english system mode unit

caliper extension lines normal distribution variation

class interval histogram numeric constraint

convert ISO precision

data mean scale

data set measure standard

dimension median statistics

Standards


This lesson relates to technology, engineering, and math standards.


Lesson Plan

Time: 10 days

1. TEACHER: Present Key Terms and Essential Questions.2. TEACHER: Distribute and introduce the exercise Review the History of Measurement.3. STUDENTS: Complete Exercise: Review the History of Measurement.4. TEACHER: Assess student work using Review the History of Meaurement Rubric.5. TEACHER: Distribute and introduce the exercise Determine English and Metric Linear

Measurements.6. TEACHER: Distribute and explain the use of the Decimal Conversion Chart.7. TEACHER: Present Scale Reading Basics.ppt.8. STUDENTS: Complete Exercise: Review English and Metric Linear Measurements.9. TEACHER: Assess the students exercise Determine English and Metric Linear Measurements using

the Determine English and Metric Linear Measurements Answer Key.10. TEACHER: Distribute and introduce the exercise Measure a Block Using Dial Calipers.11. TEACHER: Present Dial Calipers.ppt.12. STUDENTS: Complete Exercise: Measure a Block Using Dial Calipers.13. TEACHER: Present Dimension Practices.ppt.14. TEACHER: Distribute and introduce the exercise Apply Linear Dimensions.15. STUDENTS: Complete Exercise: Apply Linear Dimensions.16. TEACHER: Assess the students exercise Apply Linear Dimensions using the Apply Linear Dimensions

Answer Key.17. TEACHER: Present Introduction to Basic Statistics.ppt.18. TEACHER: Distribute a dial caliper, 27 hardwood cubes, and the exercise Using Statistics in Quality

Control.19. STUDENTS: Complete Exercise: Using Statistics in Quality Control.20. TEACHER: Assess the students exercise Using Statistics in Quality Control.


Exercise: Review the History of Measurement Mass production of medicines and consumerproducts has resulted in a modern world that enjoysa very high standard of living. However, that standardof living would not exist without measurementstandards. Consider the production of your favoritemusical compact disc (CD). Without measurementstandards, the likelihood that when you purchaseda CD it would always fit in any CD player could nothappen. Manufacturers might create the CD anysize they wanted, and you’d be stuck with a CD thatwould only work in a few players. Have you ever wondered when the need formeasurement was first recognized? Do you think ithad to do with hunting, farming, shelter, or war? Thequestion may never be answered, but it is safe to saythat measurement has existed since before recordedhistory. Every human civilization has establishedits own measuring tools and, along with them,measuring standards. The pyramids in Egypt and theRoman aqueducts in Europe are a testament to thisfact. Measurement standards came into play when thedesigners of the JPL Mars Rover failed to convert theirmetric measurement to English units before theymade a part. That error cost the Mars project a robot,and it was lost in space, literally. Supplies Supplies for this exercise include:■ Engineer’s notebook■ Pencil■ Computer with Internet access■ Engineering scale

Review the History of Measurement 1. Form a team of two. 2. Search the Internet to discover the following:

■ How measuring units came to be.■ What tools were used?■ Who the major contributors were to the

development of the devices and units used.■ What major blunders occurred because of

faulty measurement? 3. Use the following websites to start the

research.■ A Brief History of Measurement

Systems. (http://standards.nasa.gov/history_metric.pdf)

■ A Brief History of Measurement. (http://www.electro-optical.com/eoi_page.asp?h=History)

■ History of Measurement. (http://ellerbruch.nmu.edu/CS255/JONIEMI/metricsystem.html)

4. As you perform your research, use these

questions to guide you.■ According to archeological records, which

civilizations were the first to recordmeasurements?

■ Around the time of the Roman Empire theterms inch, foot, and yard were defined.What was the length of a foot based on?

■ For what reason did the French Academy ofScience create the metric system?

■ What was the Treaty of the Meter (May 20,1875)?

■ How was the length of a standard meterdefined in the year 1791?

■ How was the length of a standard meterredefined in the year 1983?

■ What was the significance of the Metric Actof 1866?

■ What were some of the early tools to helpaid in measurement?

■ What major engineering blunders wereresults of faulty measurement?

5. Each team member will prepare individual

documentation and record findings in theirjournal or engineer’s notebook.


6. The team members will discuss their findings

with their partner and compile the informationinto one of two forms of documentationas described in Option 1 and 2. Only onedocument is required for each team. Option 1: Design a book jacket (size 8 x 11 or 11 x 17)cover that depicts the history of measurement.Use the above bullets in your design along withpictures and major dates in history. The bookjacket must have a front cover and back flap.Somewhere on the front cover should be thename of the course along with your names. Option 2: Design a CD (4 x 4 ) cover that depicts thehistory of measurement. Use the above bulletsin your design along with pictures and majordates in history. The CD cover must have afront and back cover. Each cover should befront and back with pictures and information.Somewhere on the front cover should be thename of the course along with your names.

7. To complete the exercise, attach a works-

cited page to the page cover or CD cover forall of the websites you used, following propercitation style.


Exercise: Determine English and Metric Linear Measurements What do a driver looking down at a speedometerto make sure the car is within the speed limit, and achef using a tablespoon to gauge the right amountof sugar have in common? Both are examples ofmeasurements that occur millions of times every day. Modern civilization cannot exist withoutmeasurement systems. Have you ever had to movea piece of furniture only to find out that the itemwould not fit through a door? Using a tape measureto gauge the size of the door opening can save a lotof grief. The abilities to conduct, record, and convertmeasurements are prerequisite skills in the fields ofscience, mathematics, and engineering. The marketplace is global. An object that is designedin the United States may end up being manufacturedin another country. The United States is the onlycountry that uses the English system. It is becauseof this global marketplace that the dimensions ofengineered objects must often be communicatedin both English and metric units. Converting linearmeasurements to provide dual dimensioning savesthe manufacturer time, which keeps product costsdown. Supplies Supplies required for this exercise:■ Number 2 pencil■ Calculator■ Ruler - English to Metric■ Decimal Conversion Chart.pdf

Determine English and Metric LinearMeasurements This exercise provides you with a foundation ofbasic measuring skills and simple mathematicalcalculations. 1.

Review Determine English and Metric LinearMeasurements.pdf. Your instructor willdistribute a hard copy of this file.

2. Complete the questions by placing your

answers in the spaces provided.


Exercise: Use a Dial Caliper How thick is one of the hairs on your head? Could itbe measured accurately with a standard inch scale?If the smallest increment on an inch scale is 1/6 inch,then 20 average-size human hairs could fit withinthe space of a 1/16 inch gap. The required degree ofaccuracy needed is dependent on the application.If you were to build a home, a standard inch scaleis perfect for laying out walls and locating windowopenings. A dial caliper is a precision measurement tool thatis often used in the design and manufacturingof consumer products, and is, perhaps, the mostcommon of all the precision measurement tools.Engineers, technicians, scientists, and machinists alluse dial calipers every day to assist the processesof analysis, inspection, engineering design, reverseengineering, and manufacturing. Supplies Supplies required for this exercise:■ Number 2 pencil■ Inch dial caliper■ Building block

Use a Dial Caliper In this exercise, you use your knowledge of technicaldrawings and dimensioning to interpret which partfeatures must be measured and recorded. Youthen use a dial caliper to perform multiple types ofmeasurements of the actual mass-produced part tothe nearest thousandth of an inch (.001”). 1.

Review Use a Dial Caliper.pdf. Your instructorwill distribute a hard copy of this file.

2. Complete the questions by placing your

answers in the spaces provided.


Exercise: Apply Linear Dimensions If you were given the responsibility of going to a storeand purchasing a throw rug that had to fit within aroom in your home, how would you communicate theshape and size of the room to the salesperson? Given the sketching skills that you’ve developed, youwould probably sketch a top view of the room ona piece of paper. This would be useful, but a sketchalone only communicates shape information. A shape has various sizes that must be communicatedin order to make intelligent design decisions.Information about an object’s size must bedimensioned fully so that if given to a manufacturerthe object or part could be created. If a part is notdimensioned correctly, and the manufacturer createsthe part incorrectly, the problem would be thedesigner’s and the process would have to start over.This could be costly if mass producing and profitsplummet. Supplies Supplies required for this exercise:■ Number 2 pencil■ Engineer’s notebook■ Inch scale or ruler

Apply Linear Dimensions In this exercise, you apply your knowledge ofdimensioning to identify missing dimensions onmultiview drawings. You also fully dimensionmultiview sketches and properly order and locatethose on the problems below. 1.

Review Apply Linear Dimensions.pdf. Yourinstructor will distribute a hard copy of this file.

2. Complete the exercise by adding dimensions to

the multiview sketches.


Exercise: Use Statistics in Quality Control Today’s consumers are constantly trying to judge thequality of products. But what is quality? How and bywhom is quality determined? Some would say thedesigner creates specifications, which in turn dictatethe quality of a product. That quality is also based onthe acceptable value of a part within a whole product. Statistics are commonly used in manufacturingprocesses to control and maintain quality. This activitywill enable you to apply statistics in order to analyzeand determine the quality of a set of wooded cubes. Supplies Supplies required for this exercise:■ Number 2 pencil■ 3/4" hardwood cubes - 27 required■ Inch dial caliper

Use Statistics in Quality Control In this exercise, you use the inch dial caliper providedby your instructor to accurately measure and recordthe values of twenty-seven ” hardwood cubes. Due to the nature of wood and its ability to expandand contract, reference faces from which to takemeasurements must be established. 1. Locate the end grain pattern on each block;

there are two such faces on opposite sides ofthe block.

2.

Label each cube, 1 through 27, with a number 2pencil on a non-end grain face.

3.

Click the image to review Use Statistics inQuality Control.pdf. Your instructor willdistribute a hard copy of this file.

4.

To measure the size of each cube, position theblock so the caliper measuring surfaces aretouching the end grain faces.


5. Record the size of each cube on the exercise

sheet to create a dataset. The accuracy of themeasurements should be to the nearest 0.001in.

6. Complete the exercise by answering the

questions on the handout.

Summary/Questions ■ 37

Summary/Questions

Summary

In this lesson, you learned to:

■ Read a ruler.■ Create sketches using pencil and paper.■ Use hidden and centerlines in a sketch.■ Dimension a sketch.■ Set up a drawing in AutoCAD.■ Set drawing limits.■ Use snap and grid.■ Set up and use layers.■ Create an orthographic drawing in AutoCAD.■ Dimension and annotate in AutoCAD.■ Create a 3D drawing in AutoCAD.


Questions1. To set up your working area in AutoCAD, which tool would you use first?

a. Gridb. Drawing Limitsc. Snap

2. To set up your working area in AutoCAD, which tool would you use first?a. Gridb. Drawing Limitsc. Snap



5. How often do you change the grid and snap?a. The first time you begin a drawingb. Oncec. As often as needed during a design session

6. Use layers to keep drawings organized.a. Trueb. False

7. How many layers do you need for a drawing?a. Fiveb. Onec. As many as needed during a design session

8. The orthographic drawing process is the same as hand drawing or sketching.a. Trueb. False

9. Is your sketch the same as a production drawing?a. Yesb. No

10. You should plan out every production drawing with sketching before you begin to use AutoCAD.a. Trueb. False

11. There is no need to annotate a sketch to help you create a production drawing.a. Trueb. False

Copyright ■ 39


Copyright

© 2010 Project Lead The Way, Inc., All rights reserved.

All images and material contained in Design Basics: Units 1 and 3 in this document are the property ofProject Lead The Way, Inc. unless otherwise noted and are protected under federal copyright law. It isillegal to make copies and/or distribute any of the contents of this document without the permissionof Project Lead The Way, Inc. Duplication of use of this document for any reason without permissionfrom Project Lead The Way, Inc. is against federal law and may subject you to monetary and otherpenalties.

© 2010 Autodesk, Inc., All rights reserved.

Except as otherwise permitted by Autodesk, Inc., this publication, or parts thereof, may not bereproduced in any form, by any method, for any purpose. Certain materials included in this publication are reprinted with the permission of the copyright holder.

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Autodesk, AutoCAD, AutoCAD Architecture, AutoCAD MEP, AutoCAD Civil 3D, Autodesk Inventor,Autodesk Inventor Professional Suite, Autodesk Revit Architecture, Autodesk Revit MEP, Autodesk 3dsMax Design are registered trademarks or trademarks of Autodesk, Inc., and/or its subsidiaries and/or affiliates in the USA and/or other countries. All other brand names, product names, or trademarksbelong to their respective holders. Autodesk reserves the right to alter product and services offerings,and specifications and pricing at any time without notice, and is not responsible for typographical orgraphical errors that may appear in this document.

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