Port-Compatibility and Connectability Based Assembly Design

Abstract

In Computer-Aided Design, when creating the solid model of a part, the designer knows how the part will interface with other parts, however this information is not stored with the part model. For catalog parts, it would be useful to be able to embed this assembly information into the part model in order to automate the process of applying mating constraints, to reduce the assembly designer’s effort or to allow for automated exploration of alternative configurations. This research evaluates and compares different schemes for capturing the attributes of assembly interfaces and appending that information to solid models. To evaluate the various schemes, this research work introduces the concept of assembly ports, which are defined as a group of one or more low-level geometric entities that undergo mating constraints in order to join parts in a CAD assembly. The schemes studied involve (i) different combinations of ways to constitute ports and include labeling, (ii) different bases for determining port compatibility with respect to design intent, and (iii) different ways of evaluating connectability with respect to part geometry. The scheme that we conclude is best minimizes the number of ways the system will try to put parts together at the expense of effort from the solid model designer to provide more information.