In formulating the model, the system used t o i n t e r r e l a t e data i s called Functional Analysis or Value Engineering, plan through which data a r e collected. I t consists of a step-by-step job
A verb noun language, o r function
language, i s developed t o precisely describe what the product does; cost, energy and user a t t i t u d e s are allocated t o these functions; a function comparison i s made; c r e a t i v i t y by function can be carried out; and f i n a l l y a Value Standard design i s developed. Functions consist of three types. need of the product. The f i r s t focuses on the one overall The
This function i s called the T S of the product. AK
second type of functions a r e those which a r e essential t o the performance of the T S and these are called BASIC FUNCTIONS. AK Finally, functions must be
added t o make the product convenient t o use, dependable, satisfying and a t t r a c tive. These a r e called SUPPORTING FUNCTIONS. As functions are i d e n t i f i e d , there must be a means to determine higher order o r PRIMARY FUNCTIONS from lower order o r SECONDARY. Lunctional Analysis Systems Technique (F.A.S.T.) i s t h e means by which t h i s i s accomplished. The
format in Figure 1 indicates a scope 1ine, the "how"/"why" questions checking the logic, and the four PRIMARY SUPPORTING FUNCTIONS which must be expanded to cover user/customer wants. * I
For the f i r s t step in developing a F.A.S.T. diagram f o r the vacuum cleaner in the model, a group of 25 individuals from a consumer product organization asked of themselves the question, "What does a cannister vacuum cleaner with a power head do?" After some struggle they agreed on the TASK ''Clean Surfacen. They then asked "how" in terms of PRIMARY BASIC FUNCTIONS, and identified four: Provide Power Move Air Remove Dirt Store Dirt
FUNCTION ANALYSIS SYSTf MS TECHNIQUE
SUPPORTING F U N C ? IONS
(PRIMARY FUNCTIONS) FIGURE 1 \
The "howtt/"why" questions were asked to determine the lower level. i l l u s t r a t e s lower levels of the four PRIMARY BASIC FUNCTIONS. The PRIMARY SUPPORTING FUNCTIONS are: Assure Convenience Assure Dependability S a t i s f y User Attract User
The same "h~w'~/"why" questions asked of the BASIC FUNCTIONS are applied t o the SUPPORTING FUNCTIONS w i t h one difference. acceptance t o the task" i s always in mind.
An inferred clause "to achieve high
As an example, "How does the can-
n i s t e r vacuum cleaner Assure Convenience to achieve high acceptance t o the TASK--Clean Surface?" The group selected 7 S C N A Y SUPPORTING FUNCTIONS EODR
t h a t answer t h i s question: Supply Directions F a c i l i t a t e Upkeep Minimize Storage Simplify Operations Aid Service Enhance Portability Extend Reach "H~w"/~~why" questions were again asked of the 7 SECONDARY SUPPORTING FUNCTIONS t o determine a lower order. shown in Figure 3 . Each subsequent PRIMARY SUPPORTING FUNCTION has been developed in the same manner. The functions a r e next numbered and entered in a computer program The F.A.S.T. diagram f o r the T S AK The F.A.S.T. diagram f o r Assure Convenience i s
t o be used for the allocation of the data.
Clean Surface i s then rearranged (Figure 4 ) so as to be used t o obtain function cost (PART 111), function energy (PART IV) , and the function a t t i t u d e comparison (PART V ) .
Su i-i"lr f a c e
SCOPE L lM E
CANNISTER ILXXUH (U 3 S WR
TASK: C l e a n Surface
m L ~ a...