Understanding Design Iteration: Representations from an Empirical Study

Design is a cornerstone of the engineering profession and a prominent feature in how we educate engineers and accredit engineering programs. Design problems are often ambiguous, ill-structured, and may have multiple solutions. As a result, a designer’s understanding of the problem or possible solutions evolves through a process of iteration. Iteration is a symbolic feature in design models that represents a process of revisiting and resolving design conflicts. Although iteration is considered an integral part of design activity and a natural attribute of design competency, there is little research that explicitly operationalizes or represents iterative activity. The purpose of this paper is to provide and discuss theoretically meaningful representations of iteration in engineering design. Representations were generated from empirical data from a comprehensive study of cognitive processes in iterative design activity. The utility of these representations is evidenced in their ability to emphasize empirical findings, highlight qualitative trends and patterns of behavior, and distinguish differences in design success and levels of engineering experience. In addition, these representations may be useful pedagogical tools for engaging design students and design educators in discussions about effective iterative behaviors.