关键词: 前瞻算法, 非均匀有理B样条, 插补器, 加加速度控制

Abstract: An effective Non-Uniform Rational B-Spline (NURBS) interpolator with smooth acceleration curve was designed according to the practical performance in Computer Numerical Control (CNC) system and the geometric characteristics of NURBS curve. The interpolator simulated the real machining process by using fast computation to find the points where acceleration was not continuous firstly. Then, the deceleration points were computed inversely by S-shape acceleration and deceleration algorithm. The feedrate and acceleration were constrained to predict the start point of the third stage in S-shape acceleration and deceleration algorithm. By this way, not only the accuracy of deceleration points was improved, but also a smooth profile of acceleration at deceleration points was obtained. Simulation results show that the interpolator could get a smooth acceleration profile effectively while ensuring the machining accuracy.

Key words: look-ahead algorithm, non-uniform rational b-spline, interpolator, Jerk-limited