Three-Axis NC Cutter Path Generation for Subdivision Surface with Z-Map

In this paper we propose methodologies and algorithms of NC cutter path generation for subdivision surfaces. We select Loop surface as the subdivision surfaces. A path plan including rough cut and finish-cut is developed based on the LoD (Level of Detail) property of subdivision surface. We generate a coarse mesh that covers the limit surface to implement the rough cut. For finish-cut we use ball-end mills and offset cutter contact data to generate cutter location data. In these two steps we use a Z-map model and a collision detection/correction method is presented for the interference-free of these two steps. We implement our methods and present machining results. All of these two kinds of cutter paths are computed rapidly and automatically.