曲面五轴加工3D刀补的奇异点检测与处理

Singularity detection and treatment of 3D tool compensation in five-axis surface machining

曲面五轴端铣加工过程中通常应用空间刀具补偿功能来简化NC编程,但在补偿过程中刀轴矢量易出现奇异解,使机床的运动轴在该奇异位置附近发生运动突变。应用刀轴矢量投影法来检测曲面五轴端铣加工过程中的奇异点,将刀轴矢量投影在二维平面上,根据投影的长度及夹角来判断奇异点,减少了计算量,提高了检测的准确度,可快速准确地检测出空间刀具补偿过程中的奇异点。通过对奇异区域内NC程序段进行进给速度限制,实现稳速通过奇异点,可以有效地避免机床运动轴突变,提高曲面加工精度,保证机床安全运行。

In the process of five-axis end milling of curved surfaces,the space tool compensation function is usually used to simplify NC programming.However,the tool axis vector is prone to singular solutions during the compensation process,which makes the motion axis of the machine tool move suddenly near the singular position.Projection method is used to detect the singular points in the five-axis end milling process of the curved surface,the tool axis vector is projected on the two-dimensional plane,and the singular points are judged according to the projection length and included angle,which reduces the amount of calculation and improves the accuracy of detection It can quickly and accurately detect the singularity in the process of spatial tool compensation.By restricting the feed rate of the NC program segment in the singular area,the stable speed through the singular point can be realized,which can effectively avoid the sudden change of the machine tool motion axis,improve the surface processing accuracy,and ensure the safe operation of the machine tool.