Abstract
This paper describes a robust and efficient method for interference calculation between polyhedral solids. The method treats geometrical elements as incident each other when their intersection is ambiguous because of numerical errors. After the incident information is generated as topological constraints from minimal geometrical judgements, it is modified to hold consistent relations and utilized to generate a topological structure of an output solid. A cluster, which is a set of coincident intersection points, is deduced from the constraints for points, and a local structure at the intersection is determined symbolically with the face sequence around the cluster. Further, high-precision arithmetic is used partially not to cause larger errors than the tolerance. Using these algorithms, consistent results are shown to be always obtained efficiently.
