关键词: 非均匀有理B样条, 参数曲线插补, 进给速度规划, 预处理曲线, 数控系统

Abstract: In Non-Uniform Rational B-Splines (NURBS) direct interpolation algorithm,to improve real-time performance of interpolation and to overcome the shortcomings of look-ahead algorithm,the feedrate planning method was proposed based on feedrate preprocessing curve.Before interpolation,the feedrate preprocessing curves were established to substitute look-ahead algorithm of interpolation feedrate planning.To prevent the acceleration and the jerk from exceeding the machine tool's capability,a method of point to point computing was used to plan the feedrate of every parameter point in the larger changes region of curvature.MATLAB simulation result showed that the proposed method could achieve higher machining precision,smoother feedrate contours and higher real-time performance.

Key words: non-uniform rational B-splines, parametric curves interpolation, feedrate planning, preprocessing curve, numerical control systems