Analysis of cognitive processes of a designer as the foundation for support tools

Abstract. Drawing sketches while designing plays an essential role in crystallising design ideas. Past literature has revealed important aspects of sketching that facilitate design processes. There has been no empirical study, however, to reveal how sketches are involved in the very process in which the structures of designers ' actions are dynamically formed. We have devised a general scheme to code designers ' actions belonging to different cognitive levels. Based on the scheme, we analyzed the process of a practicing architect. We found evidence that suggests the following insights. First, the role of sketching is mostly to leave ideas on paper for later inspection and thus perception, rather than to give simultaneous incentives for perception. Second, the role of perception is to stimulate functional thoughts, especially in the phase of detailed exploration. Third, therefore, design behaviors are situated in the physical setting in which designers draw and perceive. Based on these insights, we have proposed the concept of a set of different types of design support tools. They should assist designers ' actions to draw and perceive while maintaining the situatedness of design behaviors. 1