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Chapter 8 Task/Customer FAST Diagram

8.1 I n t r o d u c t i o n

Two k inds o f FAST diagrams a re w ide l y used. We have a l ready discussed the techn i ca l FAST i n Chapter 4. This chapter w i l l descr ibe user, customer, o r task o r i en ted FAST diagramming. l a r k o r i en ted FAST d i a g r a m i n g r e a l l y s t a r t e d w i t h the second generat ion o f p r a c t i t i o n e r s i n the f i e l d o f va lue engineer ing. This approach emphasizes the f a c t t h a t success cannot be achieved unless users/owners' needs and des i res a re recognized, understood and f u l f i l l e d . The Task FAST mandates t h a t the user o r customer p l a y a key r o l e i n e s t a b l i s h i n g value. As discussed i n Chapter 4, t echn i ca l FAST almost always represents a p o r t i o n o f a t o t a l sub jec t , such as a product , process, e t c . I t u s u a l l y has one basic f u n c t i o n t h a t then i s expanded i n t o a c r i t i c a l path. The Task o r i en ted FAST diagram i s l ook ing a t a t o t a l product , serv lce , e tc . , and we can expect a number o f in terdependent bas ic f unc t i ons which a re necessary t o per form the task requ i red by the user/customer.

Thomas Snodgrass and Theodore Fowler, Fel lows o f t he Soc ie ty o f Amerlcan Value Engineers, developed the user/customer o r i en ted FAST diagram. F igu re 8.1 shows a schematic layout o f the user/customer Task o r i en ted FAST diagram. There a re f o u r p a r t s t o t h i s diagram:

1. Scope L ine - 2. Task - >..-

3. Basic f unc t i ons -Primary -Secondary

4. Suppor t ing Funct ions -Primary -Secondary

8.2 Task Or iented FAST D i a g r a m i n g

As i n Tech FAST, there a re s p e c i f i c steps i n developing a Task FAST diagram. Step 1, i d e n t l f y i n g the func t i ons o f the p r o j e c t , i s s i m i l a r t o t he procedure o u t l i n e d i n Chapter 4 under "Funct ion - What Does I t Do?"

The second s tep i s t o separate t he i d e n t i f i e d func t i ons i n t o bas ic and suppor t ing func t i ons . To do t h i s , I t i s necessary t o d e f i n e these two types o f f unc t i ons . Basic f unc t i ons a re those which a re e s s e n t i a l t o the performance o f t he Task. Without the baslc f unc t i on , t he product , system, e t c . w i l l n o t work. Primary basic f unc t i ons a r e those which a re connected d i r e c t l y t o t he r l g h t o f the scope l i n e , and secondary basic f unc t i ons a re those which branch o f f o f t he pr imary. Suppor t ing func t i ons , though no t e s s e n t i a l , a r e extremely impor tan t i n b u i l d i n g customer acceptance and i n s e l l i n g the product o r serv ice . There a re f o u r pr imary suppor t ing func t i ons : assure convenience, assure dependab i l i t y , s a t i s f y user, and a t t r a c t user .

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FUNCTION ANALYSIS SYSTEMS TECHNIQUE Customer-Oriented Fast

HOW?

Basic Functions Secondary I

TASK

Basic Primary

m Baslc

Supporting Functions

Convenience

-i Assure Dependabliity k

WHY?

Primary Functions

FIGURE 8.1

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The t h i r d s t e p i n v o l v e s de te rm in i ng t h e p r ima ry bas i c f u n c t i o n s o r those t h a t a r e d i r e c t l y t o t h e r i g h t of t h e scope l i n e and t h e Task. The Task I n la'sk FAST i s d e f i n e d as t h e need o f t h e customer. I t i s t h e reason t h a t t h e - produc t o r s e r v i c e e x i s t s , and t h e customer must a n t i c i p a t e o r understand t h i s need i n o rder f o r t h e p roduc t o r se r v i ce , e t c . t o have va lue . The "How-Why" ques t ions must work f o r t h e se lec ted Task and t h e p r ima ry bas i c f u n c t i o n s . These p r imary bas i c f u n c t i o n s a r e in te rdependent and, again , a r e e s s e n t i a l t o t h e performance o f t h e Task. Once t h e p r ima ry bas i c f u n c t i o n s have been i d e n t i f i e d , t h e "How?" ques t i on can be asked o f each o f t he prtrnary bas ic f u n c t i o n s . Of ten, candidates which answer t h e "How* ques t i on w i l l be found i n t h e expanding branches. These a r e t h e secondary bas i c f u n c t i o n s . There must be two o r more secondary bas i c f u n c t i o n s t o j u s t i f y branching f r om t h e p r imary f u n c t l o n . Th i s r u l e a l s o a f f e c t s f u r t h e r b ranch ing o f f t o t h e t h i r d l e v e l . Usua l l y t h e t h i r d l e v e l completes t h e b ranch ing i n bas i c f u n c t i o n s . F i gu re 8.2. i l l u s t r a t e s t h i s branching. The a c t u a l f i n a l b ranch ing i s determined when o n l y hardware i s t h e noun requi rement o f t h e f u n c t t o n .

FUNCTION ANALYSIS SYSTEMS TECHNIQUE Customer-Oriented Fast

HOW? WHY?

Baslc Functions

Prlmary Baslc SCOPE LINE Baslc

Secondary

FIGURE 8.2

The f o u r t h and f i n a l s t e p i s t o group t h e remain ing f u n c t i o n s i n t o t h e f o u r p r ima ry suppo r t i ng f u n c t i o n groups. Each o f these f u n c t i o n s has s p e c i f i c ca tego r i es ass igned t o i t .

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Support ing func t i ons p lay an impor tan t r o l e i n products or , i n t h i s case, a b u i l d i n g . S t r u c t u r a l engineers, f o r instance, concentrate p r i m a r i l y on t h e basic func t ions , w i t h heavy emphasis on t h e pr imary suppor t ing func t i on , Assure Dependabi l i ty . Mechanical engineers and e l e c t r i c a l engineers pay more a t t e n t i o n t o t he suppor t ing func t i on , Assure Convenience, w h i l e a r c h i t e c t s ' ideas s a t i s f y both t he bas ic f u n c t i o n and t h e suppor t ing func t ions , A t t r a c t User and S a t i s f y User. - Assure Convenience

Any f u n c t i o n t h a t

C1. con t r i bu tes t o s p a t i a l arrangements.

C2. f a c i l i t a t e s maintenance and repa i r s .

C3. f u rn i shes i n s t r u c t i o n s and d i r e c t i o n s t o user.

Assure Dependabi l i ty

Any f u n c t i o n t h a t

D l . makes a p roduc t / s t ruc tu re s t ronger i n t he op in ion o f t h e designer and a p p l i c a b l e codes.

02. makes i t sa fer t o use - p r o t e c t s t h e user.

D3. lengthens t h e l i f e o f t h e s t ruc tu re /p roduc t a cos t .

D4. ensures the r e l i a b i l i t y o f opera t ion .

D5. p r o t e c t s t he environment.

S a t i s f y User

Any f u n c t i o n t h a t

S1. mod i f ies the bas ic f u n c t i o n ... f a s t e r , smal ler , l i g h t e r ... e tc .

S2. o f f e r s phys i ca l comfor t .

S3. i s des i red o r wanted by owner/user.

S4. makes i t easy t o use.

S5. makes use r ' s l i f e a l i t t l e more p leasant , i .e . minimizes no ise .

A t t r a c t User

Any f u n c t i o n t h a t

A l . emphasizes the v i s u a l aspect ( s i g h t ) .

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A2. p r o j e c t s a f a v o r a b l e image (5 .e . t r a d e marks o r endorsement by p u b l i c f i g u r e ) .

A3. f u l f i l l s t h e v i s u a l e x p e c t a t i o n s o f t h e owner /user .

A4. makes t h e p r o d u c t / s t r u c t u r e appear s t r o n g e r i n t h e o p i n i o n o f t h e user /customer , b u t n o t n e c e s s a r i l y i n t h e o p i n i o n o f t h e d e s i g n e r . (Sometimes these o p i n i o n s w i l l be r e f l e c t e d i n t h e s tandards and s p e c i f i c a t i o n s o f a p a r t i c u l a r agency/owner.)

A5. u t i l i z e s a m a t e r i a l o r method t h a t t h e owner o r user p r e f e r s ( i . e . , d e s i g n i n g a b u i l d i n g f o r U n i t e d S t a t e s S t e e l C o r p o r a t i o n - a s t r u c t u r a l s t e e l b u i l d i n g ) .

The secondary s u p p o r t i n g f u n c t i o n s branch t o t h e r i g h t f r o m t h e p r i m a r y s u p p o r t i n g f u n c t i o n s when t h e "How" q u e s t i o n i s a p p l i e d . Again t h e r e must be two o r more secondary f u n c t i o n s t o j u s t i f y b ranch ing . Sometimes t h e r e a r e as many as f o u r l e v e l s b r a n c h i n g f r o m t h e p r i m a r y s u p p o r t i n g f u n c t i o n .

An i n d u s t r i a l p r o d u c t and a c o n s t r u c t i o n p r o j e c t a r e used i n t h i s c h a p t e r t o e x p l a i n t h e s teps o f a FAST diagram. To s i m p l i f y t h e e x p l o r a t i o n , t h e s teps a r e n o t p resen ted i n t h e o r d e r i n wh ich they a r e developed. As p r e v i o u s l y e x p l a i n e d , b a s i c f u n c t i o n s and s u p p o r t i n g f u n c t i o n s a r e grouped and t h e Task i s de te rm ined a f t e r a l l f u n c t i o n s a r e deve loped.

8.3 Example 1 : Prod C a n i s t e r Vacuum Cleaner ( F i g . 8.4)

"What does a c a n i s t e r vacuum c l e a n e r do?"

The answer t o t h i s q u e s t i o n i s a s e t o f verb-noun f u n c t i o n s . One d i s t i n c t i v e f u n c t i o n among a l l t h e f u n c t i o n s shou ld be t h e main reason t h a t a customer buys t h i s p r o d u c t . I n t h i s case, we w i l l ag ree t h a t t h e main reason a customer buys a vacuum c l e a n e r i s t o c l e a n t h e s u r f a c e . By d e f i n i t i o n , Clean S u r f a c e i s t h e Task o f t h e vacuum c l e a n e r ( F i g . 8 . 3 ) .

W H Y B A S I C F U N C T I O N S

( T A S K )

C L E A N 1 S I I R F A L L I

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FIGURE 8.4

11 4

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8.4 Primary Basic Functions

llHow does a vacuum c leaner c lean sur face?"

I t creates vacuum o r a negat ive pressure underneath the vacuum c leaner causing a i r t o move. As the a i r moves, i t removes the d i r t f rom the sur face and c a r r i e s the d i r t w i t h i t . The vacuum c leaner t raps t h i s d i r t be fore l e t t i n g out the a i r . Move A i r , Remove Dirt and Store Dirt a re the th ree func t i ons t h a t a re performed t o s a t i s f y t he Task, Clean Surface.

They a re the pr imary basic f unc t i ons o f the vacuum c leaner (F ig . 8 . 4 ) .

8.5 Primary and Secondary Funct ions

The bas ic func t ions l i s t e d i n F igure 8.4 are t h e pr imary l e v e l bas ic func t ions . These func t i ons can be expanded by asking the quest ion, "How does i t ( i n s e r t f u n c t i o n ) ? "

I1How does i t remove d i r t ? I 1

I t Loosens Dirt, Ent ra ins Dirt and Conveys Dirt. F igure 8.5 i s expanded t o i nc lude secondary l e v e l bas ic func t ions .

H O W fm 4 W H Y BASIC FUNCSIONS

RECEIVE AIR I MOVE

ACCELERATE AIR

(TASK) LOOSLN DIRT

REMOVE DIRr ENTRAIN DIRT

CONVtY DIRT I

S rORE ENTRAP DIRT I

DIRT CoLLEcr D I R T

8.6 Support ing Functions - Needs, Wants, Desires and Requirements

A t y p i c a l customer looks f o r a product t h a t i s dependable, convenient t o use, and a t t r a c t i v e . A market researcher prepared the f o l l o w i n g requirements f o r a vacuum c leaner:

1. I t should be smal l enough t o s to re .

2. I t should p i c k up d i r t w i thou t much e f f o r t on my p a r t .

3. I t should be maintenance-free.

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4. D i r e c t i o n s should be e x p l i c i t and s imple.

5. It should warn me when t h e bag i s f u l l .

6. It should n o t be t o o no i sy .

7. It s h o u l d n ' t r e q u i r e f r equen t bag changes.

8. I t s h o u l d n ' t be t o o d i f f i c u l t t o change bags.

9. It should be mobi le , b u t i f i t bumps i n t o f u r n i t u r e , i t should n o t cause damage.

10. I t should be a p o r t a b l e , l i g h t and compact u n i t .

11. Some customers p r e f e r a smal l r e c t a n g u l a r vacuum c leaner i n s t e a d o f c i r c u l a r - t y p e u n i t s .

12. Other customers p r e f e r c i r c u l a r u n i t s because they can be s to red i n t i g h t co rners .

13. E x t r a power t o do work f a s t e r and b e t t e r i s d e s i r a b l e .

14. Co lo r and s t y l e a r e two impo r tan t f a c t o r s .

15. I t should be equipped t o e a s i l y c l ean c rev i ces , d rape r i es , and f u r n i t u r e .

16. Opera t ing a vacuum c l eane r should be simp1 n c l u d i n g changing accessor ies .

17. I t should be a s e l f - p r o p e l l e d u n i t .

18. I t should be easy t o a d j u s t h e i g h t s o f t h e c l eane r so t h a t i t doesn ' t r u i n t h e c a r p e t .

19. Var ied s u c t i o n power i s d e s i r a b l e .

20. I t should n o t r e q u i r e much s to rage space.

21. It should p r o j e c t an image o f q u a l i t y , s t u rd i ness and r e l i a b i l i t y .

8.6.1 Secondary Leve l Suppor t ing Func t ions

These requi rements can be cons idered secondary l e v e l suppo r t i ng f u n c t i o n s :

M in im ize Storage 1 . I t should be smal l enough t o s t o r e .

M in im ize E f f o r t 2. I t should p i c k up d i r t w i t h o u t much e f f o r t on my p a r t .

A i d Se rv i ce 3. It should be maintenance-free.

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S i m p l i f y D i r e c t i o n s 4. D i r e c t i o n s should be e x p l i c i t and simple.

S igna l (Bag) Change 5. I t should warn me when the bag i s f u l l .

Reduce Noise 6. I t should no t be too no isy .

Dispose Dirt 7. I t should no t r e q u i r e f requent bag changes.

S t y l e Product 8. Some customers p r e f e r a smal l rec tangu la r vacuum c leaner , i ns tead of t h e t y p i c a l c i r c u l a r - t y p e u n i t s .

S t y l e Product 9. Other customers p r e f e r c i r c u l a r u n i t s because they can be s to red i n t i g h t corners.

Simp1 i f y Operat ion 10. I t shou ldn ' t be t o o d i f f i c u l t t o change bags.

P ro tec t F u r n i t u r e 11. It should be mobi le, bu t i f i t bumps i n t o f u r n i t u r e , i t should n o t cause damage.

Minimize Weight 12. I t should be a por tab le , l i g h t and compact u n i t . Minimize E f f o r t

Add Power 13. Ex t ra power t o do t h e work f a s t e r i s des i rab le .

Add Color 14. Color and s t y l e a re two impor tan t f a c t o r s . S t y l e Product

Clean Crevices 15. I t should be equipped t o e a s i l y c lean c rev ices , Clean Draperies draper ies, and f u r n i t u r e . Clean F u r n i t u r e

S i m p l i f y Operat ion 16. Operat ing a vacuum c leaner should be simple, i n c l u d i n g changing accessories.

Propel U n i t 1 7 . I t should be a s e l f - p r o p e l l e d u n i t .

Regulate Height 18. I t should be easy t o a d j u s t he igh ts o f t he c leaner so t h a t i t doesn ' t r u i n t h e carpe t .

Contro l Flow 19. Varied suc t i on power i s des i rab le .

Minimize Storage 20. I t should no t r e q u i r e much storage space.

P r o j e c t Q u a l i t y 21. I t should p r o j e c t an image o f q u a l i t y , s tu rd iness and r e l i a b i l i t y .

Note t h a t t h e comments and func t ions shown f o r a c a n i s t e r vacuum c leaner a re no t complete. A few f u n c t i o n examples were used t o i l l u s t r a t e t he methodology o f developing a FAST diagram.

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8.6.2 Secondary Level Support ing Functions

I t i s h e l p f u l t o d i v i d e support ing func t ions i n t o two groups--very general func t ions t h a t descr ibe the requirements o f the customer and s p e c i f i c d e t a i l e d func t ions t h a t descr ibe the a c t i o n o f an element o f the machine o r a very s p e c i f i c need o f the customer.

General S p e c i f i c

M i n imi ze Storage Reduce Noise Minimize E f f o r t Pro tec t F u r n i t u r e S i m p l i f y D i rec t i ons P ro jec t Q u a l i t y S t y l e Product Regulate Suct ion Enhance Shape Regulate Height S i m p l i f y Operat ion Signal (Bag) Change Minimize E f f o r t Minimize Weight

I n most cases, func t ions t h a t a re grouped as "General Funct ions" a re h igher order func t ions and those t h a t a re grouped as "Spec i f i c Funct ionsu a re lower order func t ions . By asking a "Why" quest ion t o s p e c i f i c func t ions , the general f unc t i ons can be developed. S i m i l a r l y by ask ing a "How11 quest ion t o a general func t ion , the secondary func t ions can be developed.

For example:

"Why does the machine have t o P ro tec t F u r n i t u r e and P ro tec t Surface?

ENVIRONMENT PROTECT SURFACE I

"How does the machine Minimize E f f o r t ?

The answer i s :

Propel U n i t Reduce Size Minimi ze Weight

- -

I ---/-PROPEL UNIT , -- - -- - - - -

MINIMIZE EFFORT REDUCE S I Z E 1 - - - - i-I-

8.7 Support ing Funct ions - C l a s s i f i c a t i o n

Using the c r i t e r i a f o r each category o f support ing func t i ons found i n F igure 8.2, the support ing func t i ons can be grouped i n t o f o u r categor ies and then i n t o secondary l e v e l support ing func t ions .

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Assure Convenience

C r i t e r i a C1: /Makes i t Easy t o Use)

Minimize Storage S i m p l i f y D i r ec t l ons Signal Bag Change

C r i t e r i a C2: S i m p l i f i e s Maintenance and Serv ice - -.

Aid Service F a c i l i t a t e Upkeep S i m p l i f y Operation

Assure Dependab i l i t y

C r i t e r i a D2: Makes i t Safer t o Use

Pro tec t Fu rn i t u re Pro tec t User Pro tec t Surface

S a t i s f y User

C r i t e r i a S2: U t i l i z e any Method t h a t User Pre fers

- - = Clean Crevices Clean Draperies Clean F u r n i t u r e

C r i t e r i a S3: (Desired by User) Make I t Eas ierh lo re E f f e c t i v e t o Use

Increase Power Regulate Height Regulate Suct ion

C r i t e r i a S4: Easy t o Use

Propel U n i t Minimize E f f o r t

C r i t e r i a S5: L i f e More Pleasant

Reduce Noise

A t t r a c t User

C r i t e r i a A1 : Visual

S t y l e Product Add Color

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C r i t e r i a A2: Pro jec ts Favorable Image

Connote Status P ro jec t Q u a l i t y

S i m i l a r func t ions were developed and c l a s s i f i e d . F igure 8.6 shows the support ing func t ions on a p a r t i a l FAST diagram o f a can is te r vacuum c leaner.

8.8 Example: Construct ion P ro jec t

Maintenance o f T r a f f i c During Reconstruct ion o f a Highway (F ig . 8.7)

Const ruc t ion o f a temporary road along the e x i s t i n g highway was proposed t o detour t r a f f i c du r ing the recons t ruc t i on o f the highway.

"What does a temporary road do?"

The b u i l d e r , user and designer des i re a temporary road f o r one reason--to main ta in t r a f f i c du r ing cons t ruc t ion . Therefore, the task o f a temporary road i s t o Main ta in T r a f f i c .

8.9 Basic Functions

"How does a temporary road main ta in t r a f f i c ? "

The temporary road detours the t r a f f i c away from the ons t ruc t i on zone so t h a t the cons t ruc t i on w i l l n o t a f f e c t the f l o w o f t r a f f i 46 --Detour T r a f f i c i s the basic f u n c t i o n t h a t s a t i s f i e s the Task, Ma in ta in T r a f f i c .

"How does the temporary road detour t r a f f i c ? "

I t should f i r s t D i v e r t the T r a f f i c away from the designated lanes and then Channel T r a f f i c through temporary lanes away f rom the cons t ruc t i on zone. A t the end o f the cons t ruc t i on zone, the temporary road should Merge the T r a f f i c i n t o the main highway. The bas ic func t ions can be summarized as:

now iB- W H Y B A S I C F U N L C I O N S

( T A S K ) D I J t R T T S A F F I C ---- r / M A I N I A I N b/ D L r O d l I t - ! ! 7

i i 7 A F F I C T R A F F I C C H A N N t L T S A F F I C 1 I I I

' '----I X E R C L i l A F l l C 1

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H O W

(TASK)

CLEAN 1 SURFACE 1

PUPPOK'TINL FUNCTIONS

- SIYPLIFY DIRECTIONS

CLEAN LXCERIOR

CLEAN FILTER I FACILITATE 2PKEEP 1

I ' DISPOSt DIRT 1 , 1 1 , 4 SIGNAL BAG LHANLt MINIMIZE SlORACL

sroat UNIT

FURNISH HANDLtS ENHANLL POKTABILITY /

REDUCt WLICHTS

I

CJSHION PACKACL 1 I

--- PRG'TEC I FURNITURE P3OTELI ENJIRON*LNl 1

PROSEL1 SJRFACt 1

CLEAN LRLVICbS 1 -- 7

CLtAN DRAPLRIES I - ( AI3S JERSATILITY / L

CLLAN FJRNITUHE 1 CLEAN tDGL5 1

PROPLL UNIT

REDUCL 51Zt 1 YINIMIZE WLICHT I

-- ~

MINIMIZL VIBRATION MINI.IZL ANNOYANCL \-(I

REDJCt NOISL

USER ADD COLOR PROJELT QUALITY 1

-{ CONNOTE STATUS 1

P R O J E L ~ VALUL

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8.10 Functions

The p r o j e c t coord ina tor of the highway recons t ruc t i on p r o j e c t summarized the needs and requirements o f the p r o j e c t based on h i s meeting w i t h var ious s ta te , c i t y and fede ra l o f f i c i a l s and the p u b l i c :

1. C i t y p re fe rs t h a t t r a f f i c should be maintained even du r ing cons t ruc t ion .

2. Federal o f f i c i a l s suggested t h a t t r a f f i c can be r e s t r i c t e d t o one lane each way du r ing cons t ruc t ion .

3 . There i s a major concern about any plans t h a t w i l l detour t r a f f i c through l o c a l s t r e e t s .

4. Speed should be reduced t o 20 MPH on a l l detours.

5 . Frequent change o f t r a f f i c pa t te rns du r ing the per iod o f cons t ruc t i on i s n o t des i rab le .

6. Numerous sharp curves i n a detour a r e n o t des i rab le .

7. Truck t r a f f i c through l o c a l s t r e e t s should be p roh ib i t ed . I t i s too no1 sy .

8. The idea o f 'temporary rou te along the cons t ruc t i on area should be considered.

9 . Construct ion o f a temporary road may increase cons t ruc t i on t ime.

10. Can the p u b l i c t o l e r a t e less inconvenience f o r a longer per iod o r more inconvenience f o r a shor te r per iod?

11. Increased t r a f f i c i n neighborhood s t r e e t s may cause more accidents. People a re concerned about t h e i r p roper ty and l i v e s .

12. D r i ve rs should a l s o be considered. I t i s n o t des i rab le t o increase the t r a v e l d is tance and subsequent t r a v e l t ime. I t wastes energy.

13. Adverse t r a v e l pa t te rns should be avojded. D r i ve rs shou ldn ' t be expected t o make too many tu rns through neighborhood s t r e e t s or deal w l t h numerous stop s igns.

14. This i s a p u b l i c undertaking. Everyth ing poss ib le should be done t o minimize cons t ruc t i on costs. Some inconvenience should be to le ra ted .

15. Necessary signs t o cau t i on d r i v e r s should be posted, and personnel should be a v a i l a b l e t o d i r e c t t r a f f i c .

16. Close the highway f o r a few weeks, expedi te cons t ruc t i ah and complete the j o b qu i ck l y .

17. Since l i m i t e d funds are ava i l ab le , cons t ruc t i on costs f o r the temporary road should be minimized.

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These needs and requi rements can be ca tego r i zed as f u n c t i o n s .

Funct ions ,

Mai n t a i n T r a f f i c

R e s t r i c t T r a f f i c

M in im ize (Neighbor- hood) D is tu rbance

Reduce Speed

Min im ize ( T r a f f i c ) Change

Avoid (Adverse) T rave l

Reduce Noise

Cons t ruc t (Temporary) Route

M in im ize ( C o n s t r u c t i o n ) Time

Min im ize Time, M in im ize Inconvenience

P r o t e c t P roper ty Safeguard Res idents

Minimze ( T r a v e l ) D is tance,

1 . C i t y p r e f e r s t h a t t r a f f i c should be ma in ta ined even d u r i n g c o n s t r u c t i o n .

2. Federa l o f f i c i a l s suggest t h a t t r a f f i c can be recons t ruc ted t o one l ane each way d u r i n g c o n s t r u c t i o n .

3. There i s a major concern about any p l ans t h a t w i l l de tour th rough l o c a l s t r e e t s .

4. Speed should be reduced t o 20 MPH on a l l de tou rs .

5. Frequent change o f t r a f f i c p a t t e r n s d u r i n g t h e p e r i o d o f c o n s t r u c t i o n i s n o t d e s i r a b l e .

6. Numerous sharp curves i n a de tour a r e n o t d e s i r a b l e .

7. Truck t r a f f i c th rough l o c a l s t r e e t s should be p r o h i b i t e d . I t i s t o o no i sy .

8. The i dea o f a temporary r o u t e a l o n g t h e c o n s t r u c t i o n a rea should be cons idered.

- 9 . Cons t ruc t i on o f a tempo y road may i nc rease

c o n s t r u c t i o n t ime .

10. Can t h e p u b l i c t o l e r a t e l e s s inconvenience f o r a l onge r p e r i o d o r more inconvenience f o r a s h o r t e r p e r i o d o f t ime?

11. Increased t r a f f i c i n neighborhood s t r e e t s may cause more acc i den t s . People a r e concerned about t h e i r p r o p e r t y and l i v e s .

12. D r i v e r s should a l s o be cons idered. I t i s n o t d e s i r a b l e t o i nc rease t h e t r a v e l d i s t a n c e and

Min im lze ( T r a v e l ) Time, subsequent t r a v e l t ime . I t wastes energy. Conserve Energy

Avoid (Adverse) T rave l , 13. Adverse t r a v e l p a t t e r n s should be avoided. D r i v e r s M i n im i ze Turns, s h o u l d n ' t be expected t o make numerous t u r n s M in im ize Stops th rough neighborhood s t r e e t s o r dea l w i t h numerous

s top s igns .

M i n im i ze 14. Th i s i s a p u b l i c under tak ing . Eve ry th i ng p o s s i b l e ( C o n s t r u c t i o n ) Cost should be done t o m in im i ze c o n s t r u c t i o n c o s t s .

Some inconvenience should be t o l e r a t e d .

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Caution Dr i ve r 15. Necessary signs t o caut ion d r i v e r s should be D i r e c t T r a f f i c posted, and personnel should be a v a i l a b l e t o

d i r e c t t r a f f i c .

Close T r a f f i c 16. Close the highway f o r a few weeks, expedi te cons t ruc t i on and complete the j o b q u i c k l y .

Minimize (Temporary) Construct ion

17. Since l i m i t e d funds a r e ava i l ab le , cons t ruc t i on cos ts f o r the temporary road should be minimized.

When a l l f unc t i ons a r e developed, func t ions t h a t c o n t r a d i c t each o ther should be i d e n t i f i e d . The f u n c t i o n which i s desi red by the user/owner should be selected as the Task.

Ma in ta in T r a f f i c , R e s t r i c t T r a f f i c , and Close T r a f f i c a re th ree func t i ons t h a t c o n t r a d i c t each other . Only one o f these th ree func t i ons can be s a t i s f i e d . A t t he beginning o f t h i s study, i t was agreed t h a t t r a f f i c should be maintained du r ing the cons t ruc t i on o f the highway. Therefore, Ma in ta in T r a f f i c was selected as the Task, and R e s t r i c t T r a f f i c and Close T r a f f i c were d l scarded.

8.11 Secondary Level Support ine Functions

The remaining f u n c t can be grouped i n t o general (p r imary) and s p e c i f i c secondary func t ions 1 o f these func t ions a re support ing func t ions .

General S p e c i f i c

Minimize (Neighborhood) Disturbance Reduce Noise Pro tec t Property Reduce Speed Safeguard Residents Minimize ( T r a f f i c ) Change Avoid (Adverse) Travel Construct (Temporary) Route Expedite Construct ion Minimize Turns

M i n imi ze Stops Caution Dr i ve r D i r e c t T ra f f i c Minimize (Temporary) Construct ion

I n most cases, general f unc t i ons can be c l a s s i f i e d as secondary support ing func t ions . Functions which a r e very s p e c i f i c a r e t h i r d l e v e l func t ions . By asking a iiHowli quest ion t o a secondary func t i on , i t s t h i r d l e v e l f unc t i ons can be developed.

IfHow does the proposed scheme Pro tec t Property?I1

I t does t h i s through the func t ions , Caution Dr i ve r , Reduce Speed, and R e s t r i c t T r a f f i c . now B- WHY

CAUTION DRIVER

R E D U C t SPEED I RES rRICT TRAFFIC

125+

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How does t h e through t h e f Construct ion.

proposed p lan Reduce (Const ruc t ion) Cost? I t achieves t h i s unct ions, S i m p l i f y Cons t ruc t ion and Min imize (Temporary)

H O W im- 4 W H Y

SIMPLIFY CONSTRULTION [ REDUCL CONS TR . LOSS I I

MIN TEMP. CONSTN

I n some cases a "How" ques t ion o f a general f u n c t i o n may be answered by another genera l f u n c t i o n and/or s p e c i f i c f u n c t i o n . The f o l l o w i n g se t o f f unc t i ons i l l u s t r a t e s t h i s s i t u a t i o n .

i-1 REDUCL NOISE 1

MINIMIZE DISTURBANLL EXPEDITE CONSTN .

8.12 Suppor t ing Funct ions - C l a s s i f i c a t i o n

Using t h e c r i t e r i a f o r each category o f suppor t ing func t i ons (Sec t ion 8.2) the suppor t ing func t i ons o f t he detour t r a f f i c scheme c be grouped i n t o f o u r ca tegor ies and then i n t o secondary l e v e l supporting: %- nc t ions .

Assure Convenience

C r i t e r i a C4: Easy t o Use

Avoid (Adverse) Trave l Min imize Congestion Assure (Loca l ) Access

Assure Dependab i l i t y

C r i t e r i a D2: Safer t o Use

P ro tec t Proper ty P ro tec t D r i v e r P ro tec t Resident

S a t i s f y User/Owner

Funct ions t h a t a re des i red by user/owner

Minimize (Neighborhood) Disturbance Cont ro l (Cons t ruc t ion) Dust Conserve Energy

F igu re 8.8 shows a p a r t i a l FAST diagram o f a detour o f a highway.

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H O W

( T A S K )

B A S L C FUNC'I 'IONS

MERGE T R A F F I C

I S i J P F O R T I N G F U N C T I O N S

M I N I M I Z E C O N G E S T I O N

A S S U R E L O C A L A C C E S S

C O N V E N I E N C L

A V O I D A D V E R S L T R A V E L

M I N I M I Z E S f O P S

R E S T R I C C T R A F F I C

C O N S L R V E E N E R G Y

C O N T R O L D U S t

I H P L I F Y C O N S f R U C T I O N

R E D U C L C O N S T 1 . C O S T H I N S E H P . L O N S r N

R E D U C L N O I S L

-+ M I N I N I Z E D I S T U R a A N C E

Page 20: FAST - Application

8.13 Functions - Thedr Role I n a Study

Why should these func t ions be def ined and c l a s s i f i e d ? Developing the func t ions 'of a p ro jec t /p roduct helps the designer t o p i n p o i n t unnecessary cost and reduce the cos t o f the p r o j e c t . Funct ion i d e n t i f i c a t i o n a l s o ensures t h a t the designer inc ludes func t ions t h a t a re important t o the ownerhser which, w h i l e adding cost , may increase the value o r acceptance o f the p r o j e c t .

I n the example, the owner/residents were very concerned about d is turbance t o the neighborhood i f the t r a f f i c was detoured through l o c a l s t r e e t s . I n one case, t he designers proposed an expensive temporary detour t o keep the t r a f f i c along the e x i s t i n g road. This p lan would increase the cons t ruc t i on cos t by $450,000 and cons t ruc t i on t ime by s i x months. The func t i on , E l im ina te Disturbance ( t o neighborhood), would cos t $450,000 and inconvenience d r i v e r s because o f prolonged const ruc t ion .

When the cos t was i s o l a t e d and a l l o c a t e d t o t h i s func t ion , c i t y o f f i c i a l s d i d n ' t h e s i t a t e t o make a dec is ion . They concluded t h a t the func t ions , Minimi ze ( cons t ruc t i on ) Cost and ~ i n i m i ze ( cons t ruc t i on1 Time, were more important than E l im inate (neishborhood) Disturbance. However, they se t c e r t a i n r e s t r i c t i o n s f o r the use o f l o c a l roads and a l l o c a t e d some money t o r e p a i r the l o c a l s t r e e t s a f t e r t he cons t ruc t i on o f t he main highway. This approach changed the func t ion , E l im ina te Disturbance, t o Minimize Disturbance. Was t h i s what the user r e a l l y wanted? Only a p rec i se verb-noun func t i on , i d e n t i f i e d through communication between t h e user and designer, can guarantee t h a t the c o r r e c t f u n c t i o n i s se lected.

8.14 Conclusion

Es tab l i sh ing func t ions and t h e i r r e l a t i o n s h i p s l ays the foundat ion f o r any so lu t i on . Functions, when p rope r l y de f ined and c l a s s i f i e d , lead the user i n the r i g h t d i r e c t i o n t o analyze, speculate and evaluate. The nex t chapters w i l l i l l u s t r a t e how expensive func t i ons can be modi f ied; how unnecessary func t ions can be i d e n t i f i e d and e l iminated; and how c r i t i c a l f unc t i ons can be emphasized and enhanced. This w i l l r e s u l t i n reduced cost ; improved o v e r a l l performance o f the p r o j e c t o r product; and the bes t va lue t o the user. The user o r customer i s the pr imary focus o f Task Or iented D iagraming.


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