Abstract: Aiming at the corner and residual problem in Contour-Parallel Offset (CPO) tool path,a three clothiod curves blending method was used to make transition optimization.The skeleton extraction method was taken to compute the corner residual region.Based on residual region,the controlled points and initial connected points were selected as feature points.The clothoid and lines were connected on the constraint of feature points,which were able to keep the transition up to C2 continuous.The experimental results showed that this method could not only clean the residual region and achieve a smooth transition machining effectively,but also minimize the machining time and improve the machining quality.

Key words: contour-parallel offset corner, tool path planning, residual region, clothoid transition, numerical control system

摘要： 针对环切刀轨中存在的拐角及残区问题,提出采用三段式Clothiod曲线光滑拼接的方法进行过渡优化。首先,借鉴骨架线提取的原理判断拐角残区并提取出残区步长|然后,在残区步长的基础上,选取过渡控制点和初始插入点作为曲线过渡的特征点|最后,在特征点的约束下,将曲线和直线进行过渡连接,并保证过渡曲线的C2阶连续。仿真加工测试结果表明,该方法能有效切除环切拐角残余并实现刀轨的平稳过渡,同时能很好地缩短加工时间和提高整体的加工质量。

关键词: 环切拐角, 轨迹规划, 残区识别, clothoid过渡, 数控系统