- Email: [email protected]
FMS-Design from the Point of View of Implementation – Results of a Case Study
COl" rig ht © I F.-\( : \[ "n- \!achillt· S\st e rns. 0"1,, . Finland . I \IHH
TR.-\I:\I:\C A:\O WORK O[SIG:-.J - CASE S fT[)I[S
FMS-DESIGN FROM THE POINT OF VIEW OF IMPLEMENTATION - RESULTS OF A CASE STUDY L. Norros, K. Toikka and R. Hyotylainen Tfchll ira / RpsfIlrch CI'II/IP of Fill/a lid. E/I'C/rira / ElIgillt'frillg Labora/ory. Oraiwari I B. SF-U2 150 Espo(l. Fill/om/
Abstract A technological
change
in tooth gear production from traditional
to
FMS-production was studied. The implementation of the FMS was followed up intensively and analyzed from the point of view of design and operation.
Regarding
the
FMS-design
it
could be
shown that
implementation
includes genuine design demands which the users responded to.
If the
spontaneous distribution of design activities is supported by a theoretically oriented training process both design and operation activities can be improved to meet the functionality requirements of FMS-production. Simultaneously prerequisites for an expanded design oriented user activity are created. Keywords Flexible manufacturing, qualitative modelling.
user centered design,
experimental
training,
INTRODUCTION It has been argued that the full exploita-
Integrating
tion of the functional benefits of the FMS - high availability, flexibility and
development, on the other hand, towards use-oriented design by system designers
quali ty - demands new kinds of design and operation practices (Jaikumar 1986; Kohler & Schultz-Wild 1985). Instead of traditional division of labour between design and operation activities, the
and, on the other hand, towards designoriented or developmental way of working by system users. These developments were
functioning of the FMS seems to require their mutual interaction and integration.
manufacturing in a
The
necessity
integration
of
has
the been
design
and
operation
means
examined as a part of a study concerning the implementation of FMS in tooth gear Finnish factory
(see
To ikka 1986) . In this paper, two results of the study are presented and discussed:
design-operationshown
by
(1)
Nathan
a
contribution of
the FMS-users
in
Rosenberg (1982). According to him, the functional properties and the economy of
compensating shortcomings of the "topdown" planning with "bottom-up " develop-
complex production systems
mental activi ties;
can never be
fully anticipated in design . The knowledge concerning
optimal
functioning
( 2) experimental training as a method of
and,
user participation in FMS-design.
consequently, the optimal design of a system is more or less a result of 'learning by ysing", by which the users have much to give to the planners .
285
286
L. :'Iiorros. K. T o ikka a nd R. H\'iitd J in e n
(1) There are considerable design demands
BOTTOM-UP DESIGN BY USERS
during the implementation phase. The into
limits
of
top-down
FMS-design
came
sight
in
system
disturbances
and
developmental
measures
during
implemen-
be
seen
table,
34
% of
disturbances
are
caused
by
incomplete
the
design . In a more comprehensive data from manufacturing
corresponding
figure
industry
was
even
the
higher,
Data that include the system disturbances
over 40 % (see Kuivanen et al . 1988) .
and the users'
Thus,
developmental and design
design
and
operation
activities were collected with logbooks,
strictly sequential
kept on each cell by the users
functions.
(six in
can
the
Finnish
tation and operation of the system.
As
in
but
are
not
partly parallel
two shifts) themselves. Time span of the data is 15 months (from September 1986 to
(2)
November 1987) . This means that - due to
remarkable. From table 1 we can see that
a significant delay of the implementation
users design measures are either caused
process
-
it only consists of events on
by
Users
contribution
disturbances
or
three cells (turning and scraping sell as
and
well as tempering plant) .
design/disturbance
The last cell
they
optimizing
to
design
are
is
preventive
activities. ratio
The
expresses
the
(milling) and the central control system
rate
were
disturbances were tackled. As can be seen
installed
follow-up
just
period.
at
Of
the
end
course,
of
the
this
has
to
different
which
the users
types
of
cover the design deficiencies
effects on our data. These will be discus-
most effectively. According to this data
sed later.
users'
operation activities are expanded
towards
design
During the time of recording there occurred
the
110 novel disturbances (see also Kuivanen
regarding
et al.
and operation.
1988; repeated disturbances could
which
traditional the
is
challence to
a
division
main
of
functions
labour
of
design
not be presented because of their unsystematic registration) and 29 users' design
(3) The design demands remain during the
measures which where either direct system
whole implementation period but the weight
developments or detailed suggestions for
of
such. These were classified according to
disturbance oriented to preventie measures.
their causing. A summary of this data
the
design
activities
shifts
from
is
presented in table 1. The main results are:
It
is
often
that
claimed
users '
developmental activities may occur during implementation the
~
Disturbance n %
Design measure n % des / dist
Cause
they disappear after
period
is
over,
routinization of activities.
due
to
In figure 1
cumulative frequencies of different types of novel disturbances and design measures
Disturbance
design failure component failure user error external factor undefined
but
transition
are given at certain points of analysis 37 34 22 8 9
34 31 20 7 8
10 5 2
34 18 7
0.27 0.15 0.09
(3, 10 and 15 months). According to figure 1 most failure rates were decreasing over the 15 months period. However, the failure rates did not approach
Optimizing/ Prevention Total
12
41
to
zero
which
indicates
that
there
is
continuous design demand in the system. 110 100
29 100
The
operators
disturbances: Table L Distribution of novel disturbances and users' design measures according to their cause.
disturbances
react As
the
prevail
sensitively component during
the
to
the
caused first
period so do also the c orresponding design measures.
In the next phase we observe a
FMS.Design from th e Point of View of Impleme ntatio n
strong increase of design failures and accordingly increasing operator activity to tackle these disturbances. During the last period of registration a shift from reacting to disturbances towards preventive by the users is and optmizing measures observed.
4S
design failure c:mp::nent failure
user error
10 IS
prevention and optlmizin<) design failure caused
{O
~t
o
failure caused
user error caused
2
4.
,
,
{O
11 14 "
m::nths
Fi gure 1 . Disturbances ( - ) and users' design treasures (- - - ) after 3, 10 and 15 rn::nths of reco.rding .
We conclude: bottom-up controlled redistribution The of design and operation functions is initiateded by the system disturbances to which the users react. The developmental attitude towards disturbances is (or can be) transformed into preventive and optimizing activities the role of which should grow as the system level is reached in the implementation and as the complexity of the system rises. However, this spontaneous bottom-up extension of users' activities may easily extinguish as a function of the general decrease of failure rates. Thus, particular means and insitutionalized forms are needed for promoting the developmental attitudes and activities of the users during normal work . Designer-user joint experimental model training could serve this function.
287
material technology and control of tempering, but they were also offered a s.c. system training designed and carried out by the researchers . System training was the first conscious measure in trying to meet the challenge of constituting the new designer-user subject and system level activity. Our assumption was that this training should contribute both to forming user qualifications and to FMS design . The results of the training experiments are analyzed here in the light of the latter aspect. We start with a brief description of the basic context and didactic principles of the training. We came to the conclusion that an adequate mastery of the system requires not only the control over the normal operation but also includes the disturbance handling and continuous optimization of the system. In order to form such qualifications in training a three level model hierarchy becomes necessary. (1) The first level is comprised of performance models i.e. algorithms for different operative situations. Essential is that the models are consciously formed. Thus it is possible to create and change procedures flexibly according to the needs of different situations. ( 2 ) In order to achieve the above goal the second level models become necessary. These are the system models. These characterize the system elements and their e. g . material f lows and interactions
manufacturing phases, control system). With the help of these, typically graphical models it was possible to study the functional principles of the system . The simulation carried out with the help of system models was a major tool in producing performance
models.
EXPERIMENTAL TRAINING AND DESIGN The progressive personnel strategy adopted
(3) Because system models corresponding to the users' needs did not exist, and
in the plant became apparent in user training . Not only did the users have highly extensive on-site and off-site in Ne-manufacturing and in training
because it was our aim to teach the users to create the models they require in operation, a third level of models became necessary. Thus, the training was started
288
L. Norros, K. Toikka and R. H ybtylainen
wi th "constructing" the FMS through following the historical development of manufacturing. This developmental history can be devided into particular phases which are materialized in the FMS itself as its system levels (machine, Ne , FMS). Through analyzing the essential changes in the economy, technology and social organization of work during the different phases it was possible to explain the elements of FMS and the complex interactions between them. In their previous tasks the users were not used to conceptual theoretically oriented working. Thus, learning was organized according to the following didactic principles: (1) The collective production of the models. For forming a genuine learning activity the models are not given as ready-made results but the trainees create them in group work and collective discussions on the basis of the preparatory work of the researchers and other experts. (2) The functional and logical connection between the models. The models are produced by ascending from simple and abstract to concrete and complex models. Models produced earlier are used as tools for creating new ones . (3) The practicability of the models. The models have to be externalized as tools of real problem solving. System training was initiated before implementation, and 9 one day training sessions were carried out. The research data collected during the training sessions include the training programmes, complete protocols of group work and discussions, and results of the modelling tasks. A detailed analysis of the data is in preparation .
system in controlling gear production. On the basis of the analysis of the actual implementation situation and the design specifications of the central control system, the researchers prepared a training session comprising three main sections: In the first the manufacturing processes and material flows of the system were analyzed and explained. In the second a functionally oriented detailed model (30 pages) of the the central control was presented and discussed. In the third section the users were asked to solve a simulation task (using the lay-out model of the system and the model of the central control) to find optimal operating strategies in a rather typical production situation with three simultaneous batches. The users had had the first experiences of the central control in operating the system the previous day . Besides the users, also the system engineer, two designers of the central control and the researchers attended the training session. After working on the simulation task the three user groups presented their solutions of optimal operation . It became evident that different groups weighted optimality criteria differently or did not always consider all the criteria. When discussing these questions it occurred that the strategy that appeared optimal (maximizing system load, minimizing transportation of palets, minimizing settings) caused a system disturbance due to a particular specification in the central control regarding the handling of empty palets in the system. In the discussion that followed the cause
The results of the last training session demonstrate most clearly how the common
of this evident deficiency was analyzed . It was found out that in an earlier phase of design the question was considered as a technical detail among others, and that the system engineer did not not see the significance of that detail for system functionali ty . This is very natural and in accordance with our assumptions of the unpredictabili ty of the innovation process .
conceptual tools can be created in training and how they affect the design process. This session was aimed at teaching the users the functions of the central control
particularly significant in this case is the fact that the deficiency in the control system could be diagnosed in the very
289
FMS-Design from th e Point o f View o f Impleme nt ati on
first functional simulation of the system. Two possible solutions were also suggested: A complete elimination of the problem by changing major principles of handling the palets or a partial solution that would leave some restrictions to be taken into account in operation. As the latter would require less resources at this stage of design it appeared the more likely to be put into effect .
This case demonstrates first that considering the design solutions from the point of view of operation reveals solutions that have to be reconsidered. Secondly, it shows that the later this interaction between design and operation is takes place the more restricted are the solutions that can be adopted. Thirdly it becomes evident that preventive consideration of design failures, i.e. enhancing the functionality of design by operative knowledge, requires new conceptual tools. The training session, the functional modelling of the control system and the simulation were all consciously created means and as such necessary for discovering this particular deficiency. Our claim is that such new means are not only needed for making the designers' results understandable for the users but they also challenge the methods used in design.
CONCLUDING REMARKS In this paper we have analyzed the implementation of an FM-system as an indicator of the functionality of the design. Our results suggest two general conclusions: First it was demonstrated that the traditional interpretation of implementation as a mere execution of the designed result is not valid in the case of creating large integrated systems characterized by high functionality demands. Instead, implementation is essentially a phase in the design itself during which many largely unpredictable operative demands can be taken into account and solved. This became evident in the analysis of the system disturbances and the users' measures of solving them.
Second we developed an experimental training concept and designed a concrete context for the manufacturing production. Our training experiment showed that the users were able to produce and use conceptual means in analyzing the production process and that these means support and systemize the design activities of the users. During the follow-up we observed the emergence of a previously not existent design oriented user activity and the corresponding subject . This "bottom-up" development was an answer to the construction demands of the new production, and it was supported by the "top-down" creation of theoretical tools. The significance of the conscious development of user design is not restricted to the implementation. It also affects the operation and design activities .
The above view on implementation also has implications for the whole design proce~s. As pointed out before implementation should be considered as part of design and should be provided resources and organized accordingly. The conceptual tools created during the training form a mediating link between the designers and users, between design and operation. It seems plausible to assume that the methods used in creating this cooperation could also contribute to developing adequate methods and practices for man-machine system design . The design activity as such was not studied in our case but on the basis of our research it appears to be a very studies.
important
object
of
further
REFERENCES Engestrom, Y. 1987 . Learning by expanding . activity-theoretical approach to developmental research. Orienta-konsulAn
tit, Jyvaskyla. Jaikumar, R . 1986. Postindustrial manufacturing. Harvard Business Review, NovemberDecember, 69-76.
L. ;\l orros. K. Toikka and R. H yo tylainen
290 Kuivanen, R., Tiusanen, R.
& Lepisto, J.
1988 . Availibility performance and safety of
flexible
manufacturing
systems
and
cells (in Finnish). To be published. Kohler,
Ch.
& Schultz-Wildt,
R.
1985.
Flexible manufacturing systems - manpower problems and policies. facturing
Systems,
Vol.
Journal of Manu4,
No.
2,
135-
146. Norros, L., Toikka, K. & Hyotylainen, R. 1988 .
Implementation of FMS:
results of
a case study (in Finnish) . To be published. Rosenberg, N. 1982. Inside the black box: technology
and
economics.
Cambridge
University Press, Cambridge. Toikka,
K.
1986.
Development of work in
FMS - case study of new manpower strategy. In: Brodner, P . (ed . ) . Skill based automated manufacturing. IFAC Workshop, Kar1sruhe, FRG, September 3-5, 1986, 7-12.
TR.-\I:\I:\C A:\O WORK O[SIG:-.J - CASE S fT[)I[S
FMS-DESIGN FROM THE POINT OF VIEW OF IMPLEMENTATION - RESULTS OF A CASE STUDY L. Norros, K. Toikka and R. Hyotylainen Tfchll ira / RpsfIlrch CI'II/IP of Fill/a lid. E/I'C/rira / ElIgillt'frillg Labora/ory. Oraiwari I B. SF-U2 150 Espo(l. Fill/om/
Abstract A technological
change
in tooth gear production from traditional
to
FMS-production was studied. The implementation of the FMS was followed up intensively and analyzed from the point of view of design and operation.
Regarding
the
FMS-design
it
could be
shown that
implementation
includes genuine design demands which the users responded to.
If the
spontaneous distribution of design activities is supported by a theoretically oriented training process both design and operation activities can be improved to meet the functionality requirements of FMS-production. Simultaneously prerequisites for an expanded design oriented user activity are created. Keywords Flexible manufacturing, qualitative modelling.
user centered design,
experimental
training,
INTRODUCTION It has been argued that the full exploita-
Integrating
tion of the functional benefits of the FMS - high availability, flexibility and
development, on the other hand, towards use-oriented design by system designers
quali ty - demands new kinds of design and operation practices (Jaikumar 1986; Kohler & Schultz-Wild 1985). Instead of traditional division of labour between design and operation activities, the
and, on the other hand, towards designoriented or developmental way of working by system users. These developments were
functioning of the FMS seems to require their mutual interaction and integration.
manufacturing in a
The
necessity
integration
of
has
the been
design
and
operation
means
examined as a part of a study concerning the implementation of FMS in tooth gear Finnish factory
(see
To ikka 1986) . In this paper, two results of the study are presented and discussed:
design-operationshown
by
(1)
Nathan
a
contribution of
the FMS-users
in
Rosenberg (1982). According to him, the functional properties and the economy of
compensating shortcomings of the "topdown" planning with "bottom-up " develop-
complex production systems
mental activi ties;
can never be
fully anticipated in design . The knowledge concerning
optimal
functioning
( 2) experimental training as a method of
and,
user participation in FMS-design.
consequently, the optimal design of a system is more or less a result of 'learning by ysing", by which the users have much to give to the planners .
285
286
L. :'Iiorros. K. T o ikka a nd R. H\'iitd J in e n
(1) There are considerable design demands
BOTTOM-UP DESIGN BY USERS
during the implementation phase. The into
limits
of
top-down
FMS-design
came
sight
in
system
disturbances
and
developmental
measures
during
implemen-
be
seen
table,
34
% of
disturbances
are
caused
by
incomplete
the
design . In a more comprehensive data from manufacturing
corresponding
figure
industry
was
even
the
higher,
Data that include the system disturbances
over 40 % (see Kuivanen et al . 1988) .
and the users'
Thus,
developmental and design
design
and
operation
activities were collected with logbooks,
strictly sequential
kept on each cell by the users
functions.
(six in
can
the
Finnish
tation and operation of the system.
As
in
but
are
not
partly parallel
two shifts) themselves. Time span of the data is 15 months (from September 1986 to
(2)
November 1987) . This means that - due to
remarkable. From table 1 we can see that
a significant delay of the implementation
users design measures are either caused
process
-
it only consists of events on
by
Users
contribution
disturbances
or
three cells (turning and scraping sell as
and
well as tempering plant) .
design/disturbance
The last cell
they
optimizing
to
design
are
is
preventive
activities. ratio
The
expresses
the
(milling) and the central control system
rate
were
disturbances were tackled. As can be seen
installed
follow-up
just
period.
at
Of
the
end
course,
of
the
this
has
to
different
which
the users
types
of
cover the design deficiencies
effects on our data. These will be discus-
most effectively. According to this data
sed later.
users'
operation activities are expanded
towards
design
During the time of recording there occurred
the
110 novel disturbances (see also Kuivanen
regarding
et al.
and operation.
1988; repeated disturbances could
which
traditional the
is
challence to
a
division
main
of
functions
labour
of
design
not be presented because of their unsystematic registration) and 29 users' design
(3) The design demands remain during the
measures which where either direct system
whole implementation period but the weight
developments or detailed suggestions for
of
such. These were classified according to
disturbance oriented to preventie measures.
their causing. A summary of this data
the
design
activities
shifts
from
is
presented in table 1. The main results are:
It
is
often
that
claimed
users '
developmental activities may occur during implementation the
~
Disturbance n %
Design measure n % des / dist
Cause
they disappear after
period
is
over,
routinization of activities.
due
to
In figure 1
cumulative frequencies of different types of novel disturbances and design measures
Disturbance
design failure component failure user error external factor undefined
but
transition
are given at certain points of analysis 37 34 22 8 9
34 31 20 7 8
10 5 2
34 18 7
0.27 0.15 0.09
(3, 10 and 15 months). According to figure 1 most failure rates were decreasing over the 15 months period. However, the failure rates did not approach
Optimizing/ Prevention Total
12
41
to
zero
which
indicates
that
there
is
continuous design demand in the system. 110 100
29 100
The
operators
disturbances: Table L Distribution of novel disturbances and users' design measures according to their cause.
disturbances
react As
the
prevail
sensitively component during
the
to
the
caused first
period so do also the c orresponding design measures.
In the next phase we observe a
FMS.Design from th e Point of View of Impleme ntatio n
strong increase of design failures and accordingly increasing operator activity to tackle these disturbances. During the last period of registration a shift from reacting to disturbances towards preventive by the users is and optmizing measures observed.
4S
design failure c:mp::nent failure
user error
10 IS
prevention and optlmizin<) design failure caused
{O
~t
o
failure caused
user error caused
2
4.
,
,
{O
11 14 "
m::nths
Fi gure 1 . Disturbances ( - ) and users' design treasures (- - - ) after 3, 10 and 15 rn::nths of reco.rding .
We conclude: bottom-up controlled redistribution The of design and operation functions is initiateded by the system disturbances to which the users react. The developmental attitude towards disturbances is (or can be) transformed into preventive and optimizing activities the role of which should grow as the system level is reached in the implementation and as the complexity of the system rises. However, this spontaneous bottom-up extension of users' activities may easily extinguish as a function of the general decrease of failure rates. Thus, particular means and insitutionalized forms are needed for promoting the developmental attitudes and activities of the users during normal work . Designer-user joint experimental model training could serve this function.
287
material technology and control of tempering, but they were also offered a s.c. system training designed and carried out by the researchers . System training was the first conscious measure in trying to meet the challenge of constituting the new designer-user subject and system level activity. Our assumption was that this training should contribute both to forming user qualifications and to FMS design . The results of the training experiments are analyzed here in the light of the latter aspect. We start with a brief description of the basic context and didactic principles of the training. We came to the conclusion that an adequate mastery of the system requires not only the control over the normal operation but also includes the disturbance handling and continuous optimization of the system. In order to form such qualifications in training a three level model hierarchy becomes necessary. (1) The first level is comprised of performance models i.e. algorithms for different operative situations. Essential is that the models are consciously formed. Thus it is possible to create and change procedures flexibly according to the needs of different situations. ( 2 ) In order to achieve the above goal the second level models become necessary. These are the system models. These characterize the system elements and their e. g . material f lows and interactions
manufacturing phases, control system). With the help of these, typically graphical models it was possible to study the functional principles of the system . The simulation carried out with the help of system models was a major tool in producing performance
models.
EXPERIMENTAL TRAINING AND DESIGN The progressive personnel strategy adopted
(3) Because system models corresponding to the users' needs did not exist, and
in the plant became apparent in user training . Not only did the users have highly extensive on-site and off-site in Ne-manufacturing and in training
because it was our aim to teach the users to create the models they require in operation, a third level of models became necessary. Thus, the training was started
288
L. Norros, K. Toikka and R. H ybtylainen
wi th "constructing" the FMS through following the historical development of manufacturing. This developmental history can be devided into particular phases which are materialized in the FMS itself as its system levels (machine, Ne , FMS). Through analyzing the essential changes in the economy, technology and social organization of work during the different phases it was possible to explain the elements of FMS and the complex interactions between them. In their previous tasks the users were not used to conceptual theoretically oriented working. Thus, learning was organized according to the following didactic principles: (1) The collective production of the models. For forming a genuine learning activity the models are not given as ready-made results but the trainees create them in group work and collective discussions on the basis of the preparatory work of the researchers and other experts. (2) The functional and logical connection between the models. The models are produced by ascending from simple and abstract to concrete and complex models. Models produced earlier are used as tools for creating new ones . (3) The practicability of the models. The models have to be externalized as tools of real problem solving. System training was initiated before implementation, and 9 one day training sessions were carried out. The research data collected during the training sessions include the training programmes, complete protocols of group work and discussions, and results of the modelling tasks. A detailed analysis of the data is in preparation .
system in controlling gear production. On the basis of the analysis of the actual implementation situation and the design specifications of the central control system, the researchers prepared a training session comprising three main sections: In the first the manufacturing processes and material flows of the system were analyzed and explained. In the second a functionally oriented detailed model (30 pages) of the the central control was presented and discussed. In the third section the users were asked to solve a simulation task (using the lay-out model of the system and the model of the central control) to find optimal operating strategies in a rather typical production situation with three simultaneous batches. The users had had the first experiences of the central control in operating the system the previous day . Besides the users, also the system engineer, two designers of the central control and the researchers attended the training session. After working on the simulation task the three user groups presented their solutions of optimal operation . It became evident that different groups weighted optimality criteria differently or did not always consider all the criteria. When discussing these questions it occurred that the strategy that appeared optimal (maximizing system load, minimizing transportation of palets, minimizing settings) caused a system disturbance due to a particular specification in the central control regarding the handling of empty palets in the system. In the discussion that followed the cause
The results of the last training session demonstrate most clearly how the common
of this evident deficiency was analyzed . It was found out that in an earlier phase of design the question was considered as a technical detail among others, and that the system engineer did not not see the significance of that detail for system functionali ty . This is very natural and in accordance with our assumptions of the unpredictabili ty of the innovation process .
conceptual tools can be created in training and how they affect the design process. This session was aimed at teaching the users the functions of the central control
particularly significant in this case is the fact that the deficiency in the control system could be diagnosed in the very
289
FMS-Design from th e Point o f View o f Impleme nt ati on
first functional simulation of the system. Two possible solutions were also suggested: A complete elimination of the problem by changing major principles of handling the palets or a partial solution that would leave some restrictions to be taken into account in operation. As the latter would require less resources at this stage of design it appeared the more likely to be put into effect .
This case demonstrates first that considering the design solutions from the point of view of operation reveals solutions that have to be reconsidered. Secondly, it shows that the later this interaction between design and operation is takes place the more restricted are the solutions that can be adopted. Thirdly it becomes evident that preventive consideration of design failures, i.e. enhancing the functionality of design by operative knowledge, requires new conceptual tools. The training session, the functional modelling of the control system and the simulation were all consciously created means and as such necessary for discovering this particular deficiency. Our claim is that such new means are not only needed for making the designers' results understandable for the users but they also challenge the methods used in design.
CONCLUDING REMARKS In this paper we have analyzed the implementation of an FM-system as an indicator of the functionality of the design. Our results suggest two general conclusions: First it was demonstrated that the traditional interpretation of implementation as a mere execution of the designed result is not valid in the case of creating large integrated systems characterized by high functionality demands. Instead, implementation is essentially a phase in the design itself during which many largely unpredictable operative demands can be taken into account and solved. This became evident in the analysis of the system disturbances and the users' measures of solving them.
Second we developed an experimental training concept and designed a concrete context for the manufacturing production. Our training experiment showed that the users were able to produce and use conceptual means in analyzing the production process and that these means support and systemize the design activities of the users. During the follow-up we observed the emergence of a previously not existent design oriented user activity and the corresponding subject . This "bottom-up" development was an answer to the construction demands of the new production, and it was supported by the "top-down" creation of theoretical tools. The significance of the conscious development of user design is not restricted to the implementation. It also affects the operation and design activities .
The above view on implementation also has implications for the whole design proce~s. As pointed out before implementation should be considered as part of design and should be provided resources and organized accordingly. The conceptual tools created during the training form a mediating link between the designers and users, between design and operation. It seems plausible to assume that the methods used in creating this cooperation could also contribute to developing adequate methods and practices for man-machine system design . The design activity as such was not studied in our case but on the basis of our research it appears to be a very studies.
important
object
of
further
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