Concurrency in product design and manufacturing process planning is supported in a recently developed sheet metal design system that incorporates preliminary process design at the detail product design stage. This new ``design with features'' approach represents the evolving part form to the designer in multiple process domains and at multiple stages of a sequential process. Each set of part form representations define the conceptualized process that transforms it from one to the other. At this modeling level, processes are reversible so that design activity can take place in any of the domains and be transformed to the others. We have fully implemented this concept in a sheet metal design/manufacturing system in which preliminary process design occurs concurrently with product design and the normal representational ambiguities of wireframe and flat panel models are eliminated.
Keywords: CAD, design with features, process design, sheet metal design