product design and development

Product Design and Development

A Generic Development Process

Concept developm

ent

System design Detail

design

Testing and

refinement

Production ramp

up

Identifying Customer Needs (Screw driver)

Define the scope of the effort

• Define description of products– A hand-held, power-assisted device for installing threaded

fasteners

• Key business goal– Product introduction in the first quarter of 2000

• Target market for the product– Do-it-yourself consumer, light-duty professional

• Assumptions that constrain the development effort– Hand-held, power-assisted, nickel-metal-hydride

rechargeable battery technology

Gather raw data from customers

• Interviews -- preferred• Focus group• Observing the product in use• Written survey is not adequate for initial

efforts

Gather raw data from customers

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10

Number of Interviews or Groups

Perc

ent N

eeds

Iden

tified

One-on-one intervew (1 hour)

Focus group (2 hours)

Gather raw data from customers

• “Lead users”: customers who experience needs months or years ahead of the majority of the marketplace– they are often able to articulate their emerging

needs, because they have had to struggle with the inadequacies of existing products

– they may have invented solutions to meet their need

Interpret raw data in terms of customer needs

Customer Statement

I like the pistol grip; it feels the best

I like the magnetized tip

Can’t drive screws into hard wood

Interpreted Statement

SD is comfortable to grip

SD tip retains the screw before it is driven

SD can screws into hardwood

Organize The Needs Into A Hierarchy

• Write each need statement on a separate card

• Eliminate redundant statements• Group the cards• For each group. Choose a label• Consider creating “super groups” • Review

The House of Quality (Quality Function Deployment - QFD)

• It is a systematic process of translating customers’ desire (voice of customers) into engineering specifications (designers’ language)

• Invented by Mitsubishi, and expanded by Toyota

• Now also used in products like swimming pool, library, construction equipment, agricultural engines

What do customers want?

• Customer attributes (CAs) -- these are customer requirements

• Typical application would have 30 to 100 CAs• List of attributes are collected via formal market

research, focus group• CAs are often grouped into bundles of attributes

that represent an overall customer concern• CAs are generally reproduced in the customers’

own word

Customer attributes and bundles of CAs

Primary

Good operations and use

Good appearance

Secondary- Easy to open/close door- Isolation- Arm rest

- Interior trim- Clean- Fit

Customer attributes and bundles of CAs

SecondaryEasy to open /close door

Tertiary- Easy to close from outside- Stay open on a hill- Easy to open from outside- Don’t kick back- Easy to close from inside- Easy to open from inside

Are all preferences equally important?

SecondaryEasy to open /close door

Isolation

Tertiary- Easy to close

from outside- Stay open on a

hill

Doesn't leak in rainNo road noise

Relative Importance

7 5

3 2

A complete list total 100%

QFD Example: Car Door Design

Easy to close 7 Doesn’t leak in rain 3

Our car

Car A

Perception

1 2 3 4 5

Customer Attributes

QFD Example: Car Door Design

Easy to close 7 Doesn’t leak in rain 3

Our car

Car A

Perception

1 2 3 4 5

Ene

rgy

to c

lose

doo

r

Doo

r se

al r

esis

tanc

e Engineering Characteristics

QFD Example: Car Door Design

Easy to close 7 Doesn’t leak in rain 3

Our car

Car A

Perception

1 2 3 4 5

Ene

rgy

to c

lose

doo

r

Doo

r se

al r

esis

tanc

e Engineering Characteristics

QFD Example: Car Door Design

Easy to close 7 Doesn’t leak in rain 3

Our car

Car A

Perception

1 2 3 4 5

Ene

rgy

to c

lose

doo

r

Doo

r se

al r

esis

tanc

e

11 ft.lb.. 3 lb./ftTarget measure

A’s car 9 ft.lb. 2 lb./ft

Relationship

Positive Negative

The House of Quality (Quality Function Deployment - QFD)

Correlation matrix

Engineering Characteristics

Customerattributes

Competitiveassessment

Relationshipmatrix

Specificationsor

target values

Customer Requirements

Importance to Cust.

Easy to close

Stays open on a hill

Easy to open

Doesn’t leak in rain

No road noise

Importance weighting

Engineering Characteristics

Ene

rgy

need

ed

to c

lose

doo

r

Che

ck f

orce

on

leve

l gr

ound

Ene

rgy

need

ed

to o

pen

door

Wat

er r

esis

tanc

e

10 6 6 9 2 3

7

5

3

3

2

X

X

X

X

X

Correlation:Strong positive

Positive

NegativeStrong negative

X*

Competitive evaluation

X = UsA = Comp. AB = Comp. B(5 is best)

1 2 3 4 5

X AB

X AB

XAB

A X B

X A B

Relationships:

Strong = 9

Medium = 3

Small = 1Target values

Red

uce

ener

gy

leve

l to

7.5

ft/lb

Red

uce

forc

eto

9 lb

.

Red

uce

ener

gy to

7.5

ft/l

b.

Mai

ntai

ncu

rren

t lev

el

Technical evaluation(5 is best)

54321

B

A

X

BAX B

A

X

B

X

A

BXABA

X

Doo

r se

al

resi

stan

ce

Acc

oust

. Tra

ns.

Win

dow

Mai

ntai

ncu

rren

t lev

el

Mai

ntai

ncu

rren

t lev

el

House of Quality Example

Linked houses from customer’s voice to manufacturing

Engineering Characteristics

Customerattributes

I

Parts Characteristics

Engineering characteristics II

Production requirement

Parts characteristics III

Customer attributes

Engineering Characteristics

Engineering Characteristics

Parts Characteristics

Production Requirement

Parts Characteristics