Automatic Detection of Manufacturing Issues in CAD Parts for DFM Analysis

This paper discusses some computational principles behind automatic manufacturability tests for CAD models of machined parts. The presented approach is a combination of automatic feature recognition supplemented with ray casting for accessibility, thickness and clearance checks. Most of the discussed approaches are applicable for different production methods, such as milling and turning (lathing) as they are purely geometric in nature. We distinguish between meshless and mesh-based methods for the analysis of manufacturing issues in a CAD part. For the mesh-based methods, two types of surface triangulation are employed: a sparse non-uniform triangulation having a relatively small number of triangles representing the geometric boundary of a part, and a dense grid covering the input part with uniform triangulation. The latter kind of mesh is constructed using quadtree-based subdivision of the UV spaces of the corresponding curvilinear trimmed surfaces.