Creating random structural descriptions of CAD models and determining object classes

Addresses two problems related to organizing CAD models represented as random parametric structural descriptions (RPSDs). First, the authors present a method to estimate the probability information for RPSDs from CAD models. The randomness arising from viewpoint variation is captured in the random variables corresponding to the attributes of the primitives and the relationship tuples. Next, and more significantly, they present a method to subdivide a large, heterogeneous set of models into smaller, structurally homogeneous subsets based on the distribution of the eigenvalues of property matrices derived from 2½ descriptions of the CAD models. Once this is done, each sublibrary of RPSDs can be hierarchically organized