Configuration Design

ConfigurationDesign

ConfigurationDesign

Special Purpose Parts: Features Arrangements Relative dimensions Attribute list (variables)Standard Parts: Type Attribute list (variables)

Abstract embodiment Physical principles Material Geometry

Architecture

Product or Part

Product configuration = “architecture” Part configuration

Start with the big picture.... i.e. Product architecture

Configuration design

ConfigurePart(s)

Configure Product

Analyzeand

Refine

Iterate

Re-examine EDS Research sourcesConfiguration requirements sketch

Best concept(s)

Design for FunctionDesign for AssemblyDesign for Manufacture

Bestconfiguration(s)

Pugh’s MethodWeighted Rating MethodEvaluate

Product architecture Integral / modular Standard / special purpose

Product First… Use component decomposition diagrams

              

penlight

bulb 

battery 

body 

spring

screw cap

glass lensfilamentbase

anodecathodeelectrolyteplastic cover

switch

case

elements are arranged into “physical building blocks”

Generalized component decomposition

Product

Subassembly AStandardPart

Standard part

Special purpose part

Special purposePart

Subassembly B 

Special purpose part

Subassembly B1

Standard part

Special purpose part

a. type, number, arrangement of componentsb. standard or special purpose (make or buy)

Product architecture …like house architecture

Architecture style Scheme

colonialdining, living rooms 1st floorbedrooms on 2nd floor

ranch all rooms on ground floor

Rooms are arranged according to a logical “scheme.”

Before the details of all the house are designed we determine the general layout or “architecture.”

Product Architecture (Ullrich & Eppinger)

def – the scheme by which the functional elements of a product are arranged into physical building blocks (components,

subsystems or subassemblies) that interact with each other to perform the overall function of the product.

Product architectures can be “modular” or “integral”

Modular architecture

Product examplesFlashlight

RefrigeratorAutomobile

Personal computer

Modular components Batteries, bulbsMotors, compressor, switchesTires, radios, seats, pumps enginesDrives, keyboards, mice, modems

• chunks implement one or a few functions, • interactions between chunks are well defined (standard interfaces / connections)

Integral Architecture

Product examples BMW Motorcycle

enginePrinter case

Shaft Beverage cup

Integrating aspectsengine/frameintegral snap-fastenersmachined bearing race integrated handle

• a single chunk implements many functions • interaction is ill defined• physical element “shares” functions

Printer Example

Cluster elements into logical chunks

Sketch rough geometric layout

Sketch interaction diagram

Part configuration design

ConfigurePart(s)

Configure Product

Analyzeand

Refine

Iterate

Re-examine EDS Research sourcesConfiguration requirements sketch

Best concept(s)

Design for FunctionDesign for AssemblyDesign for Manufacture

Bestconfiguration(s)

Pugh’s MethodWeighted Rating MethodEvaluate

Product architecture Integral / modular Standard / special purpose

What is a part configuration?

For example:Design problem: support vertical load ---- Concept: wall bracket

What are some possible “configurations” for a wall bracket?

geometry & materialPhysical principle

0

mEquilibriuForce

F

Part configuration design

geometric features include:

walls rounds cubes notches

ribs bosses spheres chamfers

projections

cylinders holes grooves

fillets tubes slots

How can we “generate” alternative part configurations?

different features

alternativearrangements

differentrelative dimensions

Abstractembodiment

Recall bracket configurations

Configuration decisions

Change one or more of these…How do we create different configurations?

Obtaining the “best” configuration

To be selective, we need a selection!

To choose the “best” alternative….

Implies that we have a number of feasible alternatives!

Configuration design - analysis

ConfigurePart(s)

Configure Product

Analyzeand

Refine

Iterate

Re-examine EDS Research sourcesConfiguration requirements sketch

Best concept(s)

Design for FunctionDesign for AssemblyDesign for Manufacture

Bestconfiguration(s)

Pugh’s MethodWeighted Rating MethodEvaluate

Product architecture Integral / modular Standard / special purpose

Continue on Tuesday

To analyze configurations, we ask…

Will it likely function?

Will it likely assemble?

Will it be likely manufacturable?

Design for function

1.  Strong2.  Stiff or flexible3.  Buckle4.  Thermal expansion5.  Vibrate6.  Quiet / Noise7.  Heat transfer8.  Fluids transport / storage9.  Energy efficient10. Stable

11. Reliable 12. Human factors/ergonomics13. Safe14. Easy to use15. Maintain 16. Repairable17. Durable (wear, corrosion)18. Life-cycle costs19. Styling/aesthetics

Will the part or product perform its function(s)?

Use knowledge from math, eng’g and sciences…

Will it assemble?

Assembly - a process of handling components

to bring them together (inserting) and then

fastening them.

What do we mean by assemble?

DFA

Design for Assembly - a set of design practices which reduce the manpower time required to

handle, insert and fasten components of a product.

1. Design Guidelines (written and graphical) 2. Cost estimating methods

DFA Graphical 1

Design for Assembly Guidelines from SME

• minimize part count • minimize levels of assembly (number of assemblies)• encourage modular assembly• use standard parts • stack sub-assemblies from the bottom up• design parts with self-fastening features (snap-fits, press-fits)• facilitate parts handling (grasp, orient, move)• design parts with self-locating features (e.g. chamfers, aligning recesses/dimples)• eliminate reorientation (i.e. insertion from 2 or more directions)• eliminate (electric) cables

DFM

Deign for Manufacture (manufacturability) - A set of practices that aim to improve the fabrication of individual parts

1. Design Guidelines (written and graphical) 2. Cost estimating methods

DFM – Injection molding / casting

• avoid designing parts with thick walls or heavy sections• design parts without undercuts • choose polymer for minimum total part cost (i.e. tooling, processing, material)• design external threads to lie on parting plane/surface• add ribs for stiffening

DFM – Sheet metalworking

avoid designing parts with narrow cutouts or projections

minimize manufactured scrap (cut-off versus blanking) reduce number of bend planes keep side-action features to a minimum or avoid

completely

DFM – Machining

employ standard features

(e.g. holes, slots, chamfers, fillets, rounds) use raw material available in standard forms

(e.g. sheet, roll, bar, plate) avoid sharp internal corners on turned parts specify liberal tolerances and surface

finishes

Configuration design - evaluation

ConfigurePart(s)

Configure Product

Analyzeand

Refine

Iterate

Re-examine EDS Research sourcesConfiguration requirements sketch

Best concept(s)

Design for FunctionDesign for AssemblyDesign for Manufacture

Bestconfiguration(s)

Pugh’s MethodWeighted Rating MethodEvaluate

Product architecture Integral / modular Standard / special purpose

Graphics during Configuration Design

Sketches are used a lot in configuration design Sketches assist creativity Sketches are not typically used to “document”

the “design”

CAD Drawings need sizes (e.g. H, W, L, D) CAD Takes time

But, some CAD may be useful

Configuration design summary

ConfigurePart(s)

Configure Product

Analyzeand

Refine

Iterate

Re-examine EDS Research sourcesConfiguration requirements sketch

Best concept(s)

Design for FunctionDesign for AssemblyDesign for Manufacture

Bestconfiguration(s)

Pugh’s MethodWeighted Rating MethodEvaluate

Product architecture Integral / modular Standard / special purpose

Configuration Design

ConfigurationDesign

ConfigurationDesign

Special Purpose Parts: Features Arrangements Relative dimensions Attribute list (variables)Standard Parts: Type Attribute list (variables)

Abstract embodiment Physical principles Material Geometry

Architecture