BUS606: Operations and Supply Chain Management

Some models decompose the design process into abstract steps independently of a mathematical formalism or analysis of inference types. One such model is the Function–Behaviour–Structure (FBS) framework. This is based on the idea that all designs can be represented in terms of: functions, which describe what the design is for; behaviours, which describe what it does; and structures, which describe what it is. FBS considers that designing occurs through eight transitions between these domains, defining the following processes: (1) formulating a problem, in which required functions are transformed into behaviours a design solution should exhibit; (2) solving the problem, through an iterative cycle in which desired behaviours are considered to create a structure representing the design, which is analysed to determine its actual behaviours, which are compared to the desired behaviours leading to design improvements "focus shifts, lateral thinking, and emergent ideas" which arise while considering the design's structure; and (4) documenting the solution. Gero and Kannengiesser extend this model to include the situated nature of design activity. They contend that design insights are generated not only from interactions within the designer's mind, as per item (3) above, but also by reinterpretation triggered when design ideas interact with the emerging design representation. To incorporate these ideas, Situated FBS decomposes designing into 20 transformation processes that transition among FBS domains in the external world, the designer's interpretation of it with respect to their emerging design, and the world they expect to produce with that design. These processes are shown in Fig. 4. Overall, Gero and Kannengiesser contend that their models differ from most others in "explicitly" representing the steps of reformulating the design and/or problem as new information is generated. Gero and Kannengeiser write that FBS and Situated FBS offer conceptual tools for understanding designing and provide bases for uniform coding of design protocols, allowing design activity to be studied independently of domain. The FBS framework and its underlying product model mentioned at the start of this paragraph have also been widely adopted to structure conceptual, computational, and empirical studies.

Other micro-level abstract models conceptualise the design process as an evolutionary system. For example, Hybs and Gero propose that the solutions considered during design can each be conceptualised as a genome, in which individual genes represent subsolutions. These authors develop a variant of FBS which illustrates that design can be viewed in terms of two genetic operators iteratively applied to a population of potential solutions: crossover, in which subsolutions are transplanted across designs, and mutation, in which subsolutions within one solution are changed by redesign. Maher and Poon apply a similar evolutionary perspective with a focus on exploration in design. In this context, exploration refers to the process by which designers come to understand more about a problem as they consider potential solution concepts. In their model, Maher and Poon propose that problem and solution can be conceptualised as evolving genomes that influence the fitness function for each other. This is described as a coevolutionary process which proceeds until problem and solution definitions are both acceptable and compatible with one another.