基于曲率加权累加的动态速度前瞻控制

针对在高速加工、快速检测等高速进给条件下,传统速度控制方法容易导致工件过切、机床抖动等问题,提出了基于离散衔接点曲率加权累加的速度前瞻程序段数动态选择的方法。首先,分析了基于5次样条曲线拟合离散衔接点方法,然后推导了到各衔接点的曲率表达式,最后根据各点曲率加权累加值进行动态速度前瞻程序段控制,并进行了仿真验证。仿真结果表明,动态速度前瞻避免了前瞻路径过短不能完成减速要求和前瞻段数过多占用系统资源,一定程度上解决了速度和精度的冲突问题,提高了系统的性能和加工效率。

Dynamic velocity look-ahead control based on weighted accumulation of curvature

As the problems of workpiece over-cut and machine chopping easily caused by conventional speed control under high speed feeding conditions as high speed machining and rapid detection,a dynamic selection method of velocity look-ahead block number was proposed based on curvature weighted accumulation of discrete points.First,the fitting of discrete joint point method was analyzed based on quintic splines.Then,curvature expressions to various discrete joint points were derived.At last,dynamic blocks of look-ahead velocity control were carried out based on curvature weighted accumulation of discrete point,and the simulation verification was conducted.The simulation result shows that the dynamic velocity look-ahead can avoid the speed reduction requirement could not complete due to over-short of the look-ahead path and the system resource is occupied due to too much number of look-ahead blocks,solving the conflict problem of speed and accuracy at some extent,and improving system performance and processing efficiency.