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MPD 575MPD 575Design for Geometric CompatibilityDesign for Geometric Compatibility

Jonathan Weaver

Cohort 8 Jack Wildman

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DFGC Development HistoryDFGC Development History

• This material was prepared by Cohort 8 students in the Fall of 2007:– Jack Wildman

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Design for Geometric Compatibility Design for Geometric Compatibility

• Needs for Geometric Compatibility• Concerns with Geometric Compatibility• Customer Driven Product Direction• Digital Vehicle Definition• Product Structure• Manufacturing Structure• Plant Structure• Geometric Requirements• Reporting Results

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Need for Geometric CompatibilityNeed for Geometric Compatibility

• Earlier verification to new customer requirements

• High Vehicle Configuration Combination complexities

• Digital Validation is Cheaper than Physical Validation

• High Cost of Tooling Rework• Ensures Proper Fit of Parts Prior to Committing

Financial Resources• Cad is the only representation of what will be

manufactured prior to prototypes

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Need for Geometric Compatibility Need for Geometric Compatibility (Cont.)(Cont.)

• Virtual Validation can be Applied in all Aspects of System Engineering – Manufacturing Process– CAE analysis– Tooling– Stamping– Serviceability– Craftsmanship– Packaging

• Customer expectations can be Visualized Early in the System Engineering Process

• Better Design from Early No Build Conditions– More Time to Correct No Build Conditions

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Concerns with Geometric CompatibilityConcerns with Geometric Compatibility

• Product Direction Letter (PDL) is not 100% defined early in Program

• Early Bill of Materials (BOM) is not stable• Requires discipline to manage CAD BOM

early in process • Geometric verification is not a high priority

early on• Design Contexts are work in progress early in

the vehicle development cycle• This is normal product development evolution

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Digital Pre Assembly (DPA)Digital Pre Assembly (DPA)Ford GPDS Process (2007)Ford GPDS Process (2007)

Supplier Integration

ProductEngineering

Theme Development

Package Development

FunctionalSimulation

Product / Process Simulation

Virtual Vehicle Realization

Service

Reports

Digital Product & Process

Integration

Plant and Facilities

Digitally Aligned•Bill of Material •Bill of Process

•CAx Product Structure

Digitally Aligned•Bill of Material •Bill of Process

•CAx Product Structure

GPDS = Global Product Development SystemGPDS = Global Product Development System

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Customer Driven Product DirectionCustomer Driven Product Direction

• Benefits of Quality Customer Direction– Shared vision by all involved activities– Proper reflection in budgets and resource plans to

execute the direction – Translation errors minimized – Order guides and broadcast (build) sheets are

accurate– Financial and supporting calculations have integrity – Parts lists and bills of material (BOM) can be

accurate • These benefits out way the concerns of

managing CAD as the actual BOM early in a program

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Poor PDL CostsPoor PDL CostsA PDL... Cost to the Company

That does not reflect Marketing intent prevents the customer from having the intended choices.

Lost customers and lower revenue – two of the most expensive losses.

That issues confusing direction prevents coordinated responses by related activities as they each add their own interpretations.

Lost time of wasted effort and resources spent on urgent recovery.

That does not reflect Engineering capability or intent can lead to releases and builds that do not reflect intended design.

Misbuilds must be rebuilt, wrong parts may be fitted affecting performance of function and a misbuild can necessitate a recall campaign.

That does not reflect the true agreement or intent of the company and its management leads to later revisions to direction.

All the work on the earlier direction is lost and the time to prove out and optimize the later design is reduced.

That is late, or action that is decided but not properly recorded, will not be reflected in department budgets or resource plans.

The constant battle for correct resources.

That has inaccurate coding of options can lead to an inaccurate BOM.

Bills of Materials (BOM) are wrong, parts associations with uses will be wrong, engineering intent may not be reflected in BOM releases and ultimately complete misbuilds can incur (including Safety or Certification Items) causing possible recall actions.

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• Late announcement of direction– If changes in direction are not made and announced in time to execute

the changes, the final product may be very late to market, or not have the development or prove out time desired, risking quality.

• Improper specification of Marketing features/options– One category of Program Direction Letter is the Features and Options

Summary, which specifies the arrangement of Standard and Optional features and series to be offered for a given product line. If that specification does not reflect the summary needs of both the Marketing communities and the Engineering groups that must design and develop a product.

• Unclear Program direction– When direction is announced via a PDL, the direction must be

sufficiently specific for the affected activities to take the expected actions. The level of detail of direction expands as a program progresses down the Product Development process. Later in a program, when actual parts are to be designed and prepared for production, a much more detailed work breakdown structure is required.

Poor PDL RamificationsPoor PDL Ramifications

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Digital Vehicle Definition Digital Vehicle Definition

• Configured CAD BOM Alignment• Variants / Effectivity = Usage• 100 % 3D Geometry Defined in Context

– Product– Manufacturing– Plant

• Full Motion (Kinematics / Dynamic)• Change Management of BOM• Market Studies• Collaboration Contexts• Ford PDM

– TeamCenter Engineering (TCe)

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• Product Development Process– Digital Verification

Vehicle Configuration Boundaries Vehicle Configuration Boundaries

Testing/Refinement

ConceptDevelopment

DetailDesign

SystemDesign

ProductionRamp up

ProductLaunch

MissionStatement

Product Planning

Ulrich and Eppinger, 1995Ulrich and Eppinger, 1995

DigitalValidation

CAD development crosses all phases

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Configured CAD BOMConfigured CAD BOM

• Cad Product structure is aligned to the Engineering BOM– Early in the Product Development Process prior to

ordering parts these are the same BOM

• The BOM consists of Usages– A usage is all of the attributes that describes how a

part is going to be used in product– We will concentrate on Variants (Why) and Effectivity

(When) a part is valid in a BOM

• The combination of effectivity and variants is called configuration

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Configured CAD BOM Configured CAD BOM Ford (TCe)Ford (TCe)

Options stored at Program

Level

Red Items System Breakdown

Pink Items Part Instances

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Configured CAD BOM Configured CAD BOM Ford (TCe)Ford (TCe)

Effectivity on Part Instances

Green “V” = Variant

Condition

Quantity required for

Program

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Configured CAD BOM (Variants) Configured CAD BOM (Variants)

• The set of variants that create a product configuration that is manufactured (buildable combination) is called a variant filter

• A variant filter is what is used to filter the product structure to different buildable combinations

• Variants/options are:– Marketing– Engineering– Procurement

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Configured CAD BOM (Variants) Configured CAD BOM (Variants) Ford (TCe)Ford (TCe)

Variant Filter

Selected Option Values

for Product

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Configured CAD BOM (Effectivity)Configured CAD BOM (Effectivity)

• Each revision of a part will use effectivity to track what revision is valid for a specific milestone (point in time)

• A effectivity filter is what is used to filter the product structure to see the coordinated revisions of the BOM

• When both variant and effectivity filters are applied simultaneously will be a set of parts that are going to be assembled at the plant

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Configured CAD BOM (Effectivity)Configured CAD BOM (Effectivity)

• Effectivity is not simple as using the current date to manage the milestones

• Actual calendar dates are mapped to a sequential hierarchical effectivity number

• The mapping is done to solve the case where in automotive the prototype phase of next model year may overlap with current production model year as to when part are due

• We will make a linear timeline stacking the model years end to end

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Each Number Increment within the Hierarchy gives Each Number Increment within the Hierarchy gives a New Block of Numbers to Manage the BOMa New Block of Numbers to Manage the BOM

1/4, 1/2, 3/4 Mod

el years

Prod

uction

/Prototyp

e P

hase

Tryou

t Bu

ild

Ph

ase

Coord

ination

P

hase

Mod

el Y

ear

1 2 3 4 567

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Model Year Management for Perpetual TimelineModel Year Management for Perpetual Timeline

PROTO 2003 PROD

PROTO 2003.5 PROD

PROTO 2004 PROD

PROTO 2003 PROD PROTO 2003.5 PROD PROTO 2004 PROD

REALITY TIMELINES OVERLAPREALITY TIMELINES OVERLAP

TIMELINES WILL BE STACKED END TO ENDTIMELINES WILL BE STACKED END TO END

3 0 0 0 000 P

S

9 9 9 9 999 E

P

3 0 1 0 000 P

3

ONE ACTUAL TIMELINE

3 0 2 0 000 03 3 5 1 0 000 P

3.5

3 5 2 0 000 03.5

4 0 2 0 000 04

4 0 1 0 000 P

4.0

3 0 2 1 100 DB

1 3 5 2 1 100 D

B

2 4 0 2 1 100 DB

3

MILESTONES CAN BE ADDED WHERE COORDINATION IS REQUIRED

3 5 2 1 110 WA

DB

23 5 2 1 010 W

BD

B 2

3 5 9 9 999 Filter

03.5

4 9 9 9 999 Filter

O4

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Configured CAD BOM (Effectivity)Configured CAD BOM (Effectivity)Ford (TCe)Ford (TCe)

Effectivity Rule Hierarchy

Effectivity Rule Names

(U502 Job 1 Buck)

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100 % 3D Geometry Defined in Context100 % 3D Geometry Defined in Context

• Product Structure needs to be partitioned into Systems and Sub-Systems– Ford Uses Corporate Product System

Classification (CPSC) codes

• All Geometry Requires a Bounding Box/Space Map to Define the Spatial Location of the Part in Context

• PDM and CAD Tools will use these Spatial Relationships for Design in Context Queries

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Configuration Rule Applied

Embedded Viewer (Design in Context)

(Clash Management)

Configured CAD BOM Configured CAD BOM Ford (TCe)Ford (TCe)

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Full Motion (Kinematics / Dynamic)Full Motion (Kinematics / Dynamic)

• Motion of any parts simulated in the context of the vehicle program

• Motion is can be stopped in worse case conditions to design proper clearances

• Motion is used by manufacturing to see if parts can loaded

• Motion of tools and access for part attachment are also required for proper design in context

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Vehicle Geometric Requirements Vehicle Geometric Requirements

• Requirements come from all activities– Design– Engineering– Manufacturing– Stamping

• Requirements are Part to Part, System to System or Part to System

• All requirements are derived over time

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Vehicle Geometric RequirementsVehicle Geometric Requirements(Ford Example)(Ford Example)

System SystemCheck Value

Type of Check

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Vehicle Geometric RequirementsVehicle Geometric Requirements(Ford Example)(Ford Example)

• Who is responsible for the interface

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Body Engineering: Hood Sub-system

DFMEA: Hood Assy

Item/Function: Jury evaluation, Fail. Mode: Squeak & Rattle, Causal Mech: Insufficient torsional stiffness

Functional requirement: Hood Torsional Stiffness (HD-0018)

DVM: Torsional Stiffness – CAE (DVM-0027-18) Torsional Stiffness – Bench (DVM-0024-HD) Torsional Stiffness – Vehicle (DVM-0025-HD)

What

Design Rules:

Parameter: Hood Beam Depth = 25mm min

Template-based parameter set Template Part

How’sAll steel inner panel main beams (periphery) must be 25mm minimum depth for the full length of the beams

HD-010205A-0001

Ford Requirements collected in SDS, stored in SetK, assessed using DVM, compliance tracked in

eFDVS, DVP&R

Parameters collected in Excel, stored in eRoom/TMT, assessed in CAD, compliance

tracked in CAD/TMT

DR’s collected in Excel , stored in eRoom, assessed in

CAD/manually, compliance tracked in Excel

Requirements Cascade (Part)Requirements Cascade (Part)

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Body Engineering: Hood Sub-system

DFMEA: Hood Assy

Item/Function: Jury evaluation, Fail. Mode: Squeak & Rattle, Causal Mech: Hood components rubbing

Functional requirement: Hood System Cycle Durability (HD-0018)

DVM: Hood System Key Life Durability (DVM-0033-HD)

What

Design Rules:

HowHood inner panel will maintain 20mm clearance to engine bay components

HD-010205A-0033

(ref. HD-0004)

Parameter: Hood Inner Clearance = 20 mm min

Geometric Checks: Hood outer to x > 20mmHood outer to y > 20 mm

CompliantFord Geometric checks

collected in Excel, stored in VVT, assessed in VIS/CAD compliance tracked in VVT

Requirements Cascade (Vehicle)Requirements Cascade (Vehicle)

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Requirements Stored in TCeRequirements Stored in TCe

RequirementsStored in program context at System

level in Excel

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Change ManagementChange Management

• The Product Lifecycle Manager (PLM)• Route Geometric Changes to Appropriate set

of Approvers for Digital Verification• Track all changes to the Product Structure

– Positional– Variant– Effectivity– Quantity– Part Number Supersedures

• Reports on health of program generated from changes tracked against usages

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Change ManagementChange ManagementFord (TCe Workflow)Ford (TCe Workflow)

Change Manages(BOM Changes)

(Effectivity)(Sign Offs)

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Manufacturing StructureManufacturing Structure

• Tooling moved to product location for combined manufacturing and product context

• This context can be launched to appropriate CAD system real time updates to fulfill geometric/functional requirements

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Manufacturing StructureManufacturing StructureFord (TCe)Ford (TCe)

Manufacturing Process in Design

Position

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Plant StructurePlant Structure

• Tooling and product moved to plant for production simulation

• Ergonomics studies can also be performed

• Can drive or fly through plant to see if any major space shortages are apparent

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Plant StructurePlant StructureFord (TCe)Ford (TCe)

Plant Layout Stations moved to

Plant Context

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ReportsReports

• The PLM system (TCe) will be used to store the product structure and design context with geometric change management authority verification sign-off

• The geometric non-compliance issues will be documented on each usage in the product structure

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Reports Reports (cont.)(cont.)

• The report will combine all non compliant issues that cross systems that can not be solves by a single system team

• The report can be parsed by system issues or individual usage issues

• The report will be scrutinized more often as major milestones are being approached– Ford uses Global Product Development Process

(GPDS) to define the Milestones.

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Correct Report to Correct PersonCorrect Report to Correct Person

Process

Deliverables

Metrics

Consumer Types

Validate Product

Verify Product

Create Product

Define Program

•Assumptions•PDL•BOM

•BOM•Clay•Geometry•CAE•Tools

•MFG Feasibility•DPA Compatibility•CAE validation•100% CAD/BOM•Attribute Validation

•Prototype Builds•Physical Testing

In Process Confidence True Measure of Exit Criteria

•CAD Completion•BOM Completion•Digital Evaluation

•Purpose ->

•Who can Fix Issue•Who Depend on the Data

•Functional Managers•Engineers •Supervisors•BLE

•Managers + -> VP•Program Management•Decision Makers

•Directors/VPs•Process Engineers

•Churn Metrics•Release Metrics•Build Performance•Total Cost

Process Capability/Efficiency

•BOM Verification•Digital Verification•Styling Status•PDPD Compliance

Progress to Plan How done am I

Design Done

BAD ChurnPlanned Churn

Desired PD Process

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HeuristicsHeuristics

• Why wait till the end to find issues, verify along the design process

• Enter once and use many

• Share info early and often

• CAD is your friend

• Prototypes are very efficient in finding issues after the money has been spent

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HeuristicsHeuristics

• Map your digital strategy and your design approach with respect to design requirements

• The percent of issues found after digital validation is proportional to the percent of errors found during physical validation

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ReferencesReferences

• Siemens. [Online] Available http://www.plm.automation.siemens.com/en_us/products/teamcenter/solutions_by_product/index.shtml, December 5, 2007.

• Ford Motor Company. [Intranet] http://www.methods.ford.com, December 5, 2007

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ReferencesReferences

• Patel, Naresh. “DPA Guidelines for Requirements”, 2006.

• Seippel, Steve. “Requirements Management”, 2007.