Fuzzy cognitive modeling with users for design system analysis

Abstract

This paper outlines a fuzzy cognitive mapping (FCM) approach for engaging users in constructing a model for engineering design system analysis. The model’s scope is drawn in reference to a socio-technical system and demonstrated with an assembly production system (a socio-technical system archetype). In particular, this paper focuses on modeling an existing assembly production system that needs to be re-designed, then analyzing the system models to inform the re-design task. The modeling approach engages users as participants (18 in this research) in observation and interviews, and these data are coded into adjacency matrices and fuzzy cognitive maps separately then integrated. The ability to model multiple users and technical entities together in breadth and detail, qualitatively and quantitatively, enables designers to zoom in to see the detail and zoom out to see a holistic perspective. The models are analyzed for overall cause, effect, and central variables. Through the FCM analysis of these variables, the elements of the existing design solution are made explicit, including inputs, external and boundary constraints, design principles, outcomes and outputs, function, and operations and structure. This is particularly useful in re-design, as demonstrated in the industrial re-design project here, where the FCM models make the current system design explicit and their analyses inform re-design intent by being synthesized into re-design foci and tasks.

Appendices

Appendix A: Transcript excerpt and FCM coding

Interviewer: How would you describe the current assembly process?

Participant: Umm… simplified.

Interviewer: Ok

Participant: You know, we’ve, over the years we’ve gone from doing a few hundred now to probably [XX] …so, and, um, we’re currently struggling with space and personnel. So we’ve, it’s grown into its own type of department within a department now and we’re struggling to staff it accordingly and be efficient at it. Now that we don’t have a lot of room in our building we’re unable to bring everything down and lay it all out ahead of the run. Usually what you’d like to do is bring everything down, let’s say you are going to do 200 [assemblies], you want to bring every piece of that [assembly]…all the [X], all the [Y], all the componentry, bring it down, make sure it’s all accurate, check it over, sign off on it, and then say “ok… let’s build.” That’s the efficient way. Now, we currently have to bring it in pieces, so at multiple times our material handlers are going to gather the pieces rather than doing it once due to our lack of space…. [interview continues]

See Table 11.

Table 11 Interview excerpt sample coding

Appendix B: Integrated interview plots (interviews 1, 2 and 3)

See Figs. 15 and 16.

Fig. 15

FCM plot for interviews 2 and 3

Fig. 16

FCM plot for integrated interviews 1, 2, and 3

Appendix C: Codes from participant interviews

See Table 12.

Table 12 Interview codes