关键词: 二阶泰勒逼近算法, 复杂曲面, 公差约束, 环形刀, 宽行加工

Abstract: To improve the efficiency of complex surfaces machining with toroidal tools, an approach about the tool path planning of strip-maximization machining is proposed by combining with the design tolerance zone. According to second-order Taylor approximation method, the strip width within the entire tool path is calculated, and then its adjustability is assessed based on the predefined strip-width-ratio threshold. For these adjustable tool path, the cutting contact points(CCPs) which decrease the strip width are analyzed. Each point of them is transformed into another actual CCP with a reasonable translation distance along the normal vector on the corresponding surface, where the value is in the constraints of tolerance zone. Thus the optimal strip-width is obtained. The influence analysis of strip-width from surface characteristic indicates that the theory based on the tolerance constraints is versatile. Example shows that the strip-width calculated by the proposed method is significantly expanded by 26.5%, comparing to second-order Taylor approximation method. Meanwhile, the length of the CCPs path is shortened by 22.7%. Therefore, the simulation result verifies the effectiveness in the complex surface machining with toroidal cutters.

Key words: Sculpture surface, Second-order Taylor approximation method, Strip-maximization machining, Tolerance constraints, Toroidal tool