论文部分内容阅读
针对复杂曲面的数控加工,提出一种基于Bézier曲线的刀具轨迹数据压缩算法.根据连续小线段的几何特征来筛选适用于被压缩的区域,将各个区域内的形值点转化为特殊的3阶Bézier曲线,选用最小二乘法拟合形值点,通过调整参数曲线控制点和插入过渡曲线,使得加工路径光顺并保证G2连续性,采用2阶Taylor展开来估计误差和控制拟合精度.结果表明:所提出的算法无迭代、实时性好,算法数据的压缩比高;采用Taylor展开估计的误差与真实误差很接近,可以有效控制拟合精度.
Aiming at the NC machining of complex surface, a tool data compression algorithm based on Bézier curve is proposed.According to the geometric features of continuous small line segment, the suitable compressing area is selected, and the value points in each area are transformed into special 3-order Bézier curve, the least square method was used to fit the shape value points, and by adjusting the parameter curve control points and inserting the transition curves, the processing path was smoothed and the G2 continuity was guaranteed. The second order Taylor expansion was used to estimate the error and the control fitting accuracy. It shows that the proposed algorithm has no iteration, good real-time performance and high compression ratio of the algorithm data. The error estimated by Taylor expansion estimation is very close to the true error, which can effectively control the fitting accuracy.