基于S型曲线加减速的数控加工刀具运动优化控制

CNC Machining tool Motion Control Optimization Based on S-curve Acceleration/Deceleration Method

数控机床加工折线时,存在因进给系统反复骤停而加工效率低、加工冲击大等问题.提出折线光滑转接加工优化控制算法,在指定加工误差的条件下,通过引入转接段降低实际转接点附近轨迹精度,从而实现了转接时的速度连续,并给出了转接速度的约束控制条件,对锐角、钝角转接进行了误差分析,验证了控制算法的有效性.针对由直线段和圆弧段组成的连续曲线整体加工控制问题,建立基于S型曲线加减速的加工控制模型,分析了圆弧半径对算法效率的影响.最后针对S型曲线加减速算法中加加速度存在阶跃变化的缺陷,提出了一种加加速度连续的改进算法,从而提高了加工质量.

Due to repeated arrests of CNC feed system,it brings several problems as low processing efficiency and high processing impacts when CNC machining workpieces with segment trajectory.In this paper,a broken line smooth transferring optimization control algorithm is put forward which realize the continuity of velocity in transferring points by introducing a transfer segment to reduce the trajectory accuracy around real transferring point at specified processing error,the constraint control conditions of transfer velocity is also derived,moreover,the error analysis of acute angle and obtuse angle are done respectively and the effectiveness of this control method is verified.For the machine control problem of continuous curve which consisted of straight line and circular arc,a processing control model is established on the basis of S-curve acceleration/deceleration method,and the efficiency of the algorithm by the change of radius is also analyzed.Finally,an improved algorithm is proposed for the defect that it exist step changes of jerk in the S-curve acceleration/deceleration method which improves the processing quality.