数控系统小线段高速加工中的“拐点问题”

在数控系统的连续小线段高速插补中，由于线段终点速度不为零及插补的离散特征，线段最后插补点与终点不能自然重合，若强行把终点作为最后插补点，可能带来速度冲击．为解决这一问题，本文提出了一种全新的处理方法，在确保没有速度冲击的前提下，允许插补点不通过线段终点，简化了插补算法．该方法产生的最大轮廓误差仅取决于最大加速度及插补周期，在实际系统中进行误差控制十分方便．

Inflexion Problem in High-Speed Machining of Small Line Blocks

In order to improve machining speed of small line blocks, the feed rate at the end of a line would be nonzero according to CNC interpolation algorithm. Because interpolation is a discrete process, the end point of the line cannot be used as an interpolation point exactly. If the end point was defined as an interpolation point compulsively, there may be a speed impact. Therefore, a new method was presented in this paper to solve the problem, which made the end point no more an interpolation point and simplified the algorithm. The maximum contour error from this method only depends on the maximum acceleration and the interpolation period. Consequently, the contour error can be controlled easily in real CNC system.