A sketch support system based on behavior of designers

We have developed a design-support system which enhances design ideas by activating divergent thinking and convergent thinking of a designer, and offers a natural user interface that does not interrupt the thinking of a designer using the faculty of a computer. The system is composed of three user interfaces (UI)-a historical-view UI which analyzes partitions and branches of a design process automatically and displays them in the form of a tree structure, a spatial-view UI with which a designer can freely arrange past sketches in two-dimensional space, and a time-line and partial undo/redo UI which provides free undoing/redoing in units finer than a stroke-based on the results of analysis of a typical design process (i.e., designing a car), behavior analysis on several designers participating in a drawing experiment, and previous research. The effectiveness of this system was confirmed by the results of evaluation experiments with professional designers.