Welcome to Engineering Design

• What is engineering design, really?

• Function to form• Design process• Phases of design• Product realization process • Roles for engineers• Concurrent engineering• Teamwork• Summary

(Mechanical) Engineering Design

machines sketch / draw customer desires mechanisms predict behavior company constraints motion test / experiment synthesize alternatives energy conversion materials analyze manufacturing evaluate

Activities integrated with topics

Activities Topics

Design Manufacturing Engineering & Materials Graphics Lectures Labs Design Project

What is Design, really?

Which of the following is design and which is analysis?

A. Given that the customer wishes to fasten together two steel plates, select appropriate sizes for the bolt, nut and washer.

B. Given the cross-section geometry of a new airplane wing we determine the lift it produces by conducting wind tunnel experiments.

Design Analysis

 Form is the solution to a design problem.

How are Function and Form related

Design

controlholdmoveprotectstore 

decision making processes

shapeconfigurationsizematerialsmanufacturing processes

Function

Form

Form Ever Follows FunctionLuis Sullivan

 

 

 Form Ever Follows Function.

Design – definition

Set of decision making processes and activities

to determine the form of an object,

given the customer’s desired function.

Making Decisions? Use the design process

Establish functional requirementsDetermine constraintsSet performance targets

GeneratingAlternatives

FormulatingProblem

AnalyzingAlternatives

EvaluatingAlternatives

Create alternative forms(shape, configuration, size, materials, manufacturing processes)

all alternatives

feasible alternatives

Redesigniteration

Design specifications

best alternative design candidateManufacturing specifications

Are there “phases” of design?

How do design decisions change over time?

Is there a logical grouping of decisions?

Example design problem - Stop a spinning shaft

(8 inch diameter, 1000 lbs, steel, 3000 rpm)

•Decide upon a satisfactory rate of deceleration •Determine the length of the shaft•Determine where it is supported•Determine what actuating energy is available•Decide to reverse engineer an existing product•Choose to research brakes in the library

“Formulation” Phase

Early in the design process, we decide upon the specifics of the function to be performed:

Decisions relating to concept?

•1. surface friction (e.g. drum brake, disk/caliper)•2. opposing magnetic fields (e.g. inverse motor)•3. air friction (e.g. fan blades) Assume we decide on surface friction

Decide physical principles that will perform the function

“Concept Design Phase”

Decisions on configuring products and new components?

Product configuration: disk/caliper, or drum, or band brake

location on shaft (right. left, middle) (Assume we decide on a disk/caliper brake) Part configuration:

relative size of hub to diskrelative size of rotor thickness to diameter

“Configuration Design” Phase

Decide upon product components & how they are arrangedDecide upon part features & how they are arranged

1. rotor diameter (outer)2. rotor thickness3. brake pad width4. pad material5. hydraulic pressure on piston

Values for Parameters?

Decide upon specific values for design variables

“Parametric Design” Phase

•machined rotor tolerances•pad bonding resin•assembly/testing procedure

Completing the details

“Detail Design” Phase

Decide upon the remaining manufacturing specifications

Function ---- stop a spinning shaft

Final “Form” is the solution to a design problem

Form•rotor: 10 inch diameter, steel, 3/8-inch thick, cooling passages•forged steel caliper/housing •brake pads, 2 opposing, 4 sq. in., metal particles/epoxy matrix•steel piston,1-inch diameter, with elastomeric seals•100 psi hydraulic piston pressure

Design Phases

Formulation

Detail

Parametric

Configuration

Concept

Embodiment Design

Preliminary Design

Design versus the Product Realization Process?

Industrial Design

Engineering Design

Production Design

Manufacturing(Production)

Distribution

Service Disposal

CustomerNeed

RealizedProduct

Sales / Marketing

Phases in the life of a product

Manufacture

Retire

Design

Use

establish functiondetermine form

fabricateassembledistribute

set upoperatemaintainrepair take down disassemble recycledispose

To satisfy the consumer…We must consider all the phases in the life of a product

Income

Investment

Introduction Growth Maturity Saturation Decline

Sales

Time

Product Development

Product realization begins the Product Life Cycle

How do we, as engineers, fit into the PRP?

  (U.S. Department of Labor, 2000).

Manufacturing 

732 50

Engineering Services 

401 27

Government (Federal, State & Local) 179 12

Self-employed 

43 3

Other   

110 8

Total   

1465 100

Employer

 Thousands %

Where do engineers work?

Engineering Roles in Design & Manufacturing Job Title Description Sales & Marketing

Sales Engineer Meets customers, determines needs, presents product offerings

Applications Engineer Assists sales & marketing solving technical issues with respect to the use of product

Field Service Engineer Installs, maintains and repairs equipment at customers’ sites

Research & Development

Industrial Designer Establishes essential product appearance, human factors

Design Engineer Decides part or product form including: shape, size, configuration, materials, and manufacturing processes

Materials Engineer Investigates and develops improved materials

Test Engineer Designs and conducts performance and safety tests

Engineering Roles in Design & Mfg

Manufacturing Industrial Engineer Designs fabrication, assembly and warehousing systems

Manufacturing Engineer

Develops manufacturing tools and fixtures

Quality Control Engineer

Establishes and maintains raw materials and finished goods quality controls

Processing / Operations

Plant Engineer Designs and maintains processing plant facilities

Project Engineer Coordinates project work tasks, budgets and schedules

typical manufacturing company

 

“Functional” organization chart

P u rc h a s ingE stim a tingE x p e d iting

P u rc h a s ing

P ro d u c tio n O p e ra tio nsQ u a lity C ontrolInd u s tria l E ngine e ringM a nu fa ctu ring E ng ine e ringP ro d u c tion P la nningT o o ling

M a nu fa c tu ring

D e s ig n Eng ine e ringInd u stria l D e s ignP ro to ty p ingT e s tingM a te ria ls R e se a rch

R e se a rc h & D e v e lo p m e nt

S a le sC u s to m er S e rv iceM a rk e tingA d v ertis ing

S a le s & M a rk e ting

A c co u ntingB u d g e tingP la nning

F ina nce

P re s id e nt

B o a rd o f D ire c to rs

S to c k h o ld e rs

Design Engineering

Mfg. Engineering

 Production

SalesMarketing

ProductManager

Industrial Design

Industrial Engineering

 Purchasing

Concurrent engineering design team

No more“over the wall”

Teamwork is a professional team sport!

Professional Team Industry

Competitors Companies

Team owners Investors

Coaches Managers

Referees, umpires Lawyers, judges

Communication Coordination

Fumbles, injuries Mistakes, losses

Individual skills Specialized jobs

Team skills “People” skills

Summary

• Design is “decision” making• Product realization process includes engineering

design• Design process requires formulating, generating,

analyzing, evaluating, refining• Form follows function• Product realization is a professional team sport