7/28/2019 dfx.pdf

1/5

81. DFX

81.1. DEFINITION

DFX, or design for X , can be defined as a knowledge-based approach that

attempts to design products that maximize all desirable characteristicssuch

as high quality, reliability, serviceability, safety, user friendliness,

environmental friendliness, and short time-to-marketin a product design

while at the same time minimizing lifetime costs, including manufacturing

costs.

Historically, designers have tended to underemphasize or overlook the

preceding factors and have concentrated their efforts on only three factors:

the function (performance), features, and appearanceof the product that

they develop. They have tended to neglect the downstream considerations

that affect the usability and cost of the product during its lifetime.

AT&T Bell Laboratories recognized the need to satisfy these objectives and

used the term DFX to designate designing for all desired factors. DFX was

described as a design procedure in which the objective broadly covers cost-

effective downstream operations: distribution, installation, service, and

customer use. Reliability, safety, conformance to environmental regulations,

and liability prevention are also objectives. These are in addition to low

manufacturing costs. DFX is the process where the full life-cycle needs of

the product are addressed during the products design. AT&T made note of

the value of incorporating DFX knowledge into CAE/CAD (computeraided

engineering/computer aided design). Education was stated to be essential.

2

3

DFX

http://accessengineeringlibrary.com/http://accessengineeringlibrary.com/http://accessengineeringlibrary.com/http://accessengineeringlibrary.com/http://accessengineeringlibrary.com/browse/design-for-manufacturability-handbook-second-edition/p2000af109979_25001?UserEmailParamInPdfDownloadController=rameshsmit@gmail.com#p2000af108999_27003http://accessengineeringlibrary.com/browse/design-for-manufacturability-handbook-second-edition/p2000af109979_25001?UserEmailParamInPdfDownloadController=rameshsmit@gmail.com#p2000af108999_27002http://accessengineeringlibrary.com/browse/design-for-manufacturability-handbook-second-edition/p2000af109979_25001?UserEmailParamInPdfDownloadController=rameshsmit@gmail.com#p13n-login-panelhttp://accessengineeringlibrary.com/

7/28/2019 dfx.pdf

2/5

81.2. THE ATTRIBUTES OFA GOOD DESIGN

The following design objectives have been recommended as being most

important.

81.2.1. Function and Performance

These are still vital. The product must perform the task for which it is

designed.

81.2.2. Safety

Those involved in the manufacture, sale, and use of the product and other

persons must be protected from physical injury and illness. A sound design

from the safety standpoint is one whose manufacturing process does not

involve hazards to workers; it is one whose operation poses the minimum

risks to the user and those in the vicinity; it is one which, when the product is

discarded after its useful life, does not entail hazardous waste.

81.2.3. Long-Term Quality

That is, quality, reliability, and durability (the customer tends to group these

objectives together; the designer should also). Will the product continue to

provide its desired function over a period of time? Will it retain its

appearance, its accuracy, its ease of use, etc.? Quality and reliability result

from care and attention at a number of stages, but perhaps the most

important stage is the design stage. Quality and reliability cannot be built in

if the basic design is not conducive to them.

81.2.4. Manufacturability

This includes testability, shipability, etc.all the objectives of DFM.

81.2.5. Environmental Friendliness

This is closely related to safety but affects all living creatures and plant life.

Will the product, its manufacturing process, its use, and its disposal avoid the

release of pollutants and other environmental hazards? The manufacturing

process should be one that generates minimal pollution. The product itself

7/28/2019 dfx.pdf

3/5

should be nonpolluting and, as noted above, nonhazardous in its operation

and disposal. Even if nonhazardous, are its components configured so that

they can be recycled easily? Design for the environment (DFE) has been

used as a term to describe this approach. Designfor disassembly is the name

given to the system of product design that emphasizes recyclability of

components. Primarily, this involves designs that ensure that recyclable

components can be separated easily from the rest of the product.

81.2.6. Serviceability (Maintainability and Repairability)

This involves the ease with which the product can be returned to use after

some failure has occurred, or the ease with which it can be attended to to

avoid future failures. This objective is closely related to reliability. Easy

serviceability may compensate for what otherwise would be a reliability

problem.

81.2.7. User Friendliness, or Ergonomics

This involves how well the product fits its human users, how easy it is to use.

(Human factors engineering was a previously common term for the discipline

that this involves.) Is the product easy for the user to install and operate?

Are all functions and controls clear? User unfriendliness can lead to safety

and reliability problems as well as make the product less functional.

81.2.8. Appearance (or Aesthetics)

This is the attractiveness of the product, which may be a very important

factor in its salability, particularly with many consumer products.

81.2.9. Features

The accessories, attachments, and peripheral functions, like the stereo, air-

conditioning, and cruise control in an automobile, may be more important to

the buyer than its basic function, i.e., in the case of an automobile,

transportation.

81.2.10. Short Tlme-to-Market

This is how suitable the design is for short lead-time production. This

7/28/2019 dfx.pdf

4/5

Copyright McGraw-Hill Education. All rights reserved.

Customer Privacy Notice. Any use is subject to the Terms of Use, Privacy Notice and

copyright information.

For further information about this site, contact us.

Designed and built using Scolaris by Semantico.

normally means whether the design is one that requires unique long lead-

time tooling for some of its components. Short time-to-market has important

implications in the current era where product designs change rapidly and

where commercial success often hinges on being the first supplier to market

a product with particular features. The company that puts an innovation on

the market first often reaps ongoing benefits in the form of increased market

share for its product.

Other objectives such as installability, testability, shipability, upgradeability,

easy customizing, etc., also may be important in many cases.

REFERENCES

[3.] James G. Bralla, Designfor Excellence, DFX, McGraw-Hill, New York, 1996.

[2] David A. Gatenby, Design for X (DFX): Key to Efficient, Profitable

Product Realization, in J. A. Edosomwan and A. Ballakur (eds.), Productivity

and Quality Improvement in Electronics Assembly, McGraw-Hill, New York,

1989, Chap. 45.

[3] R. A. Layendecker and B. Suing Kim, From DFMA to DFX: An AT&T

Example,paper presented at the 1993 DFM Conference at the National

Design Engineering Conference, Chicago, March 1993.

Citation

James G.Bralla: Design for Manufacturability Handbook, Second Edition. DFX,

Chapter (McGraw-Hill Professional, 1999, 1986), AccessEngineering

EXPORT

http://www.semantico.com/http://accessengineeringlibrary.com/contacthttp://accessengineeringlibrary.com/privacy-noticehttp://accessengineeringlibrary.com/terms-and-conditionshttp://accessengineeringlibrary.com/ris/design-for-manufacturability-handbook-second-edition/p2000af109979_25001http://accessengineeringlibrary.com/browse/design-for-manufacturability-handbook-second-edition/p2000af109979_25001

7/28/2019 dfx.pdf

5/5