Generation of offset surface for tool path in NC machining through level set methods

摘要

Surface offset is always necessary for ball-end milling during computer-aided manufacturing period. Self-intersection may occur in offsetting complex surfaces. Many solutions for surface self-intersection are always complicated with algorithms for approximation, and they are always based on surfaces which are represented by special mathematical expressions. This paper proposes level set methods in the surface offsetting progress. The surface offset problem is regarded as the generation of a new interface from a dynamic initial surface with constant normal speed. Numerical computing results demonstrate that accurate solutions can be obtained through the level set methods with an appropriate numerical flux. The self-intersections are naturally eliminated while topology stability is kept. Keywords Offset surface - Tool path - Level set - Self-intersection This project is supported by the National Natural Science Foundation of China (no. 50675199) and the Science and Technology Project of Zhejiang Province (no. 2006C11067), China