Abstract: The polyhedral model is widely used in aerospace, automotive, shipbuilding, mould and die industries. However, apart from the iso-planar method, the tool path generation methods for polyhedral machining are very limited. In such a case, the given tool paths are no longer boundary-conformed or efficient. In order to reduce the number of interruptions and rapid traversals during high-speed machining (HSM) process, a constant scallop tool path generation method is proposed. A parametric surface is firstly used to approximate the local neighborhood of a vertex and an algorithm for offset of curve on Triangular surface is developed. On this basis, an accurate tool path is generated by means of the contour offset on triangular surface. Results demonstrate that the proposed method is boundary-confirmed, and can significantly improve the machining efficiency and precision.

Key words: Curve offset, Tool path, Triangular surface, Corrosion, Modulation ratio, Multilayer, Salt spray, Tribology, Diamond-like carbon