Abstract
Features are meaningful abstractions of geometry that engineers use to reason about components, products, and processes. For design activity, features are design primitives, serve as the basis for product representations, and can incorporate information relevant to life-cycle activities such as manufacturing. Research on feature-based design has matured to the point that results are being incorporated into commercial CAD systems. The intent here is to classify feature-based design literature to provide a solid historical basis for present research and to identify promising research directions that will affect computer-based design tools within the next few years. Applications of feature-based design and technologies of feature representations are reviewed. Open research issues are identified and put in the context of past and current work. Four hypotheses are proposed as challenges for future research: two on the existence of fundamental sub-feature elements and relationships for features, one that presents a new definition of design features, and one that argues for the successful development of concurrent engineering languages. Evidence for these hypotheses is provided from recent research results and from speculation about the future of feature-based design.