基于经线划分的非圆截面环形刀具刀位优化算法

目前环形刀具的刀位算法均未考虑圆刀片安装时存在的俯仰角和偏转角,因而在理论上存在较大的编程误差。针对实际使用刀具为非圆截面环形刀具的情况,通过对环形刀具的截面曲线进行分析,提出了一种基于经线划分的非圆截面环形刀具刀位优化算法。首先利用经线法求解出刀具表面和工件曲面之间的误差分布,然后根据此误差分布来调整刀具位置和姿态,使刀具表面与设计曲面在不发生干涉的情况下实现密切接触,从而得到刀具在指定定位点处的最优刀位。仿真结果表明,传统的五坐标刀位算法会产生较大的加工误差,而本文提出的算法消除了圆刀片安装时存在的俯仰角和偏转角所引起的加工误差,可有效提高复杂曲面的加工精度并获得满足给定编程公差的优化刀位。

A Tool Positioning Algorithm Through Longitude Separation Approach for a Cutter with Non-circle Generatrix

Currently,most five-axis tool positioning algorithms with a torus cutter do not consider the mounting inclination of the round inserts.This will thus lead to large programming errors in theory.In practice,the actual torus cutter is often non-circle generatrix.To solve the problem,the section curve of the cutter is analyzed,and a tool positioning algorithm through longitude separation approach for a cutter with non-circle generatrix is presented in this article.First of all,the tool surface is discretized into insert sections to obtain the error distribution between the tool and the design surface.Then,the tool position and orientation are adjusted according to the above-mentioned error distribution in order to make the tool contact the theoretical workpiece surface as closely as possible without gouging.Thus the optimal tool position is achieved.Simulation results show that the traditional five-axis tool positioning algorithms produce large machining errors,while the proposed algorithm can eliminate machining errors resulting from the mounting inclination of the round inserts,improve the sudace machining accuracy,and generate the optimal tool position under given programming tolerance.