A practice on parametric curve interpolator based on NURBS

In this paper, some improvements in parametric curve interpolation algorithm for non-uniform rational B-spline (NURBS) is proposed, the new algorithm can generate smooth and jerk-limited acceleration/deceleration feedrate profile. In order to avoid sudden change of velocity and achieve high machining quality around the corners with large curvature, velocity will be reduced before arriving the corners, where the chord errors are larger than limited value. More importantly, the computation of the length of NURBS curve in off-line process or real-time machining will be discarded, which is considered as an indispensable procedure in NURBS interpolation algorithm. Also some improvements are given in this paper to estimate the values of u. Simulation results demonstrate the effectiveness of the proposed interpolator for machine curved paths.