Chapter 2 continued

Quality Function Deployment

What is Quality Function Deployment (QFD)?

• QFD is a tool that translates customer requirements into the engineering characteristics

Customer Requirements

Engineering Characteristics

GFD requires that customers requirements be expressed as measurable design targets in terms of engineering parameters.

Statistics on QFD• 71% of US companies adopted QFD (based on 150 US

companies surveyed)• 83% Surveyed believed using QFD had increased

customer satisfaction with their products• 76% felt it facilitates rational design decisions• QFD is a time consuming process and requires

considerable commitment of time and effort.• Most companies however, report that the time spent in

QFD saves time later in design, especially in minimizing changes caused by poorly understanding the problem.

House of quality format for QFD.

4Engineering Characteristics

1Customer

Requirement

2CompetitiveAssessment

3

7 Absolute Importance8 Relative Importance

9 Technical Competitive assessment

10 Technical difficulty

Impo

rtan

ce R

atin

g

5Correlation Matrix

6Relationship Matrix

11 Target Value

Product Design Specification (PDS)

• PDS is a document which contain all of the facts related to the outcome of the product development.

• It should contain realistic constraints that are imposed on the design.

• Creating the PDS finalizes the process of establishing the customer needs and wants, prioritizing them, and beginning to cast them into a technical framework so that design concepts can be established.

Elements found in a PDS

• In-Use Purposes and Market:– Product title, product function, predictable

unintended uses the product may be put to, special features of the product, what types of products will the product compete against and who makes them, what is intended market?, relationship of the product to other company products, anticipated market demand, target company selling price and estimated retail price

Elements Found in PDS cont’d

• Functional Requirements– Functional performance-flow of energy, information,

materials; operational steps; efficiency; accuracy– Physical requirements-size, weight, shape, surface finish– Service environment-temp., pressure, humidity– Life cycle issues-useful life, reliability, robustness,

maintainability, diagnosability, testability,repairability, installability, retairement from service and recyclability, cost of operation.

– Human factors- Aesthetics, man-machine interface, ergonomics, user training.

Elements Found in PDS cont’d

• Corporate constraints– Time to market– Manufacturing requirements– Supplies– Trademark– Financial performance– Corporate ethics

Elements Found in PDS cont’d

• Social, Political, and Legal Requirements– Safety and environmental regulations– Standards– Safety and product liability– Patents and intellectual property