Rethinking Design Theory

This article reviews a concept borrowed from psychology that has given perspectives on product development. Much progress has been made in new areas opened by the systems-level approach to engineering design. Among them are advancements in our understanding of decision-making, ideation, collaboration, modularity, requirements modeling, lifecycle considerations, robust design, green design, and various other "design for x" strategies. The rethinking of design that is needed now is a conceptual basis that allows engineers to better describe and solve problems at the system level, problems that involve user interaction. The concept we propose to deal with these problems is affordance, a term borrowed from perceptual psychology and popularized by the psychologist Donald Norman is his book The Design of Everyday Things. As the theoretical tenets of design are brought up to date with the increasing demands of systems-level design, systems integration, global marketplaces, new materials, new processes, and other recent demands, we anticipate continued growth and advancement in the field of design theory that will benefit all engineers and designers.