High-level product representation for automatic design reasoning

A high-level product representation has been developed and implemented, using features for part description and mating conditions between features for the relationship among parts. The underlying ideas are that features are necessary for effective design representation; that spatial and functional relationships among parts of an assembly are best expressed through mating conditions; that assembly features of a part may, at times, be different from its manufacturing features; and that a good representation should be natural, intelligent, comprehensive, and integrated with a visual display. Some new mating conditions have been defined and classified. Several problems concerning the use of features with mating conditions are discussed.