Computer-based sketching and the productivity of the conceptual stage of design
Mustafa, Janan Abdulsattar
Many designers find computer-based tools are not as effective during the early stages of design as manual sketching. However, to abandon the computer in these conceptual stages denies designers the computer‟s capability to translate and supplement imaginative design thinking. Recent design studies address conceptual design. What is the impact of computer-based drawing and sketching on designers‟ cognition and productive reasoning? This research focuses on the relationship between the characteristics of sketching using the drawing environment of the computer and the productivity of the conceptual design phase. I provide a theoretical framework that identifies and clarifies both sketching and productivity. Previous specialized studies are selective and sometimes only descriptive in defining this relationship. A review of these studies reveals a gap in our understanding of those aspects of sketching that relate to visualization, imagination and the generation of design ideas. The thesis addresses three objectives: (i) to build a comprehensive theoretical framework that on one hand defines the characteristics of sketching that might affect the generation of design ideas, and on the other hand defines the productivity of conceptual design and its indicators; (ii) to apply this framework in a practical study; and (iii) to extract implications for the relationship. To address the problem of computer-based sketching, I indentify the continuity within the dynamic field of images usually generated while designers sketch as the most effective characteristic of the computer sketching process. I establish a measure of continuity defined by (i) the degree of ease in projecting design images, (ii) the degree of continuity of displaying images due to changing the status of the design objects and due to navigation around the objects, (iii) the degree of provision of a holistic view (i.e., the total view of the design objects on the computer screen). Then I define productivity within this framework in terms of the cognitive operations of dialogical reinterpretation. When sketching, designers seem to perform key operations such as interpreting, reframing and restructuring. I present the case that a process rich with these cognitive operations is productive. The study makes use of the fields of free hand sketching, literature, cognitive psychology and Gestalt theory. Four indicators emerge from this study: the occurrence of pattern discovery, conceptual reinterpretation, alternation of thinking, and restructuring. I identify key variables that define the degree of continuity of the dynamic field of images which relate to designer‟s performance to verify their relationship with productivity. I study ten design participants who are given a design task that involves sketching with various CAD systems. The study involves 21 hours of recorded video analyzed using a method adapted from Goldschmidt's “linkography” tool for representing design protocols. I identify where patterns of relationships between variables exist, and where they do not apply. Not all the selected variables of continuity of the dynamic field of images, nor all the indicators of productivity in the conceptual design phase, support these patterns of relationships. This indicates that there is a special group of characteristics of sketching that maintain the pace of continuity within the dynamic field of images can improve the productivity in the conceptual phase.