During the early stages of design exploration, designers and architects tend to treat freehand sketching as a mirror of their minds. The spontaneity of conventional sketching is undoubtedly important for the designer’s thinking process. CAD systems and their contrived interfaces do not offer the advantages that sketching does. But, can modern technology offer a tool that the designers would readily accept for their creative explorations?

The research is based on a visualisation of a hypothetical system in which the designer creates a representation of three-dimensional shapes of reasonable complexity while sitting in front of a terminal. Using his gestures and limited speech, he inputs into the computer an online representation of shape. This feedback is available to the designer live on his monitor. The experiments reported here test this hypothetical system using simulation.

Gestures involve spatial movements, and they could be more convenient tools for the designers to express spatial ideas. This paper aims to identify the potentials and limitations of natural gestures as a source of shape information by focusing on shape modelling in the computer during the design process.