A New Perspective for Risk Management: A Study of the Design of Generic Technology with a Matroid Model in C-K Theory - Principia Designae: Pre-Design, Design, and Post-Design - page 190

(see Aximatic Design (AD) (Suh 1990 ) , General Design Theory (GDT)
(Yoshikawa 1981 )). And the methods and theories deal with robustness by
supporting the design of a solution that bot fit with the functional require-
ments and can support variations around this target. The design deals with a
form of local invariance.
- On the other hand, the issue to “identify” the set of requirements that should
be addressed by design. Some theories will focus on the way to identify this
set. In Coupled Design Process (GDT) (Braha and Reich 2003 ), the set of
“requirements” is built during the process, since at each stage, the closure
space of the tentative design leads to integrate new functions in the design.
AD and GDT, can also be re-interpreted in this perspective: since the theories
actually propose ways to address a given set of functions, as long as the
design space follows some properties (Hausdorff space by GDT; axiom of
independence between Functional Requirements (FR) and Design Parameters
(DP) by AD), it means more generally that these theories offer ways to
deal with complete functional spaces that follow these properties. In this
case, robustness can be understood as the capacity to design a solution for
large functional spaces, that follow specific properties. Or: if the “context”
follows certain structural properties, then a design is possible. For instance in
AD: if the “context” can be described a set of FR and if the FR and the DP
follow the “independence” axiom, then a design is possible. The same
for GDT: if the entity space is structured like a Hausdorff space, then a
design is possible. This perspective explains that if the “invariant”—ie the
context, like FR-DP and their relationship in AD- follows a certain structure,
then the design is possible. This also holds for CDP and Infused Design
(ID) (Shai and Reich 2004a ; Shai and Reich 2004b ) : CDP explains the effect
of closure on the design; ID explain how to design by making use of
structures in multiple domains.
To summarize: design theories and methods deal with robustness in two
ways: either they address the issue of local invariance or they help to address
global invariance by adding specific conditions on the structure of invariance;
but they hardly study the interaction between varied structures of invariance
and the design space, ie the effect of certain structures of invariance on the
design and conversely the sensitivity of design to certain structures of
invariance.
Note that C-K theory can accept an invariance in K (see in particular
(Hatchuel and Weil 2007 )) and, contrary to other theories, does not make any
hypothesis on the structure of invariance. This explains why it was possible to
use C-K theory to study how the notion of “face force” emerged from an
original “infused design” process in which the structures of two design
domains didn't correspond exactly, the “hole” in the two invariant structure
being the wellspring of an innovative design process. Hence it seems interest-
ing to use C-K theory to study the consequence of certain invariance structures
on design.