Exploratory making: Shape, structure and motion

•In design exploration, generative rules can both construct and alter physical models.•Shape rules can modify both rigid parts and their connections in kinematic designs.•Manipulating physical models of kinematic designs affords an appreciation of motions.•Exploratory making to systematically alter designs can help to explain how they work.•Unsuccessful changes promote the discovery of allowable limits for design variation.

Exploratory making activities can support the reasoning processes through which new designs are developed. With a focus on physical model-making of kinematic designs, this paper considers how these activities and processes can be articulated using formal generative rules. For kinematic designs where connections between parts afford relative motions, rule-based descriptions defining variable spatial relationships can both construct and transform models. Through modifying both shape and structure, spatial relations essential for achieving the motion characteristics of a kinematic design are identified. Unsuccessful modifications support discovery of limits to design changes, illuminate how designs work, and inform the generation of new design variations. The need for active manipulation of physical models, both to examine motions and to implement design changes, is highlighted.