S-Model Speed Planning of NURBS Curve Based on Uniaxial Performance Limitation

As more complex curves are used in current productions, curve speed planning has become a key technique to overcome the bottleneck of high-speed and high-precision computerized numerical control (CNC) systems. This paper first establishes the model of particle velocity, acceleration, and jerks in the Cartesian coordinate system, and then improves the uniaxial performance limit algorithm. We set up a real-time speed planning process of spline curves, design an S-model look-ahead algorithm, simplify the S-model speed planning algorithm, and achieve real-time non-uniform rational B-splines (NUBRS) curve S-model speed planning based on uniaxial performance limitation. The simulation results show that all the actual interpolation velocity, acceleration, and jerk under the proposed method meet the preset single-axis limit. The experimental results show that the tracking performance under the proposed method has been significantly improved compared with that under the small line segments method. Compared with the NUBRS curve trapezoidal model speed planning, the vibration spikes during machining can be eliminated.