Feedrate Optimization for Spline Interpolation In High Speed Machine Tools

A feedrate optimization technique has been developed for minimizing the cycle time in machining spline toolpaths. Axis velocity, torque and jerk limits are considered throughout the motion in order to ensure smooth and linear operation of the servo drives with minimal tracking error. Feed modulation is achieved by manipulating segment durations which define the overall minimum jerk feed profile. Long toolpaths are handled by applying a windowing technique. The optimized feed profile allows nonzero acceleration and jerk values at segment connections, resulting in continuous and smooth motion within the velocity, torque, and jerk limits of the drives. The cycle time reduction obtained with the proposed technique is demonstrated in high speed contouring experiments.