Accurate control of ball screw drives using pole-placement vibration damping and a novel trajectory prefilter

摘要

This paper presents a pole-placement technique to achieve active vibration damping, as well as high bandwidth disturbance rejection and positioning, in ball screw drives. The pole-placement approach is simple and effective, with an intuitive physical interpretation, which makes the tuning process straight-forward in comparison to existing controllers which actively compensate for structural vibrations. The tracking performance of the drive is improved through feedforward control using inverted plant dynamics and a novel trajectory prefilter. The prefilter is designed to remove tracking error artifacts correlated to the velocity, acceleration, jerk and snap (fourth derivative) of the commanded trajectory. By applying the least-squares method to the data from a single tracking experiment, the prefilter can be tuned quickly and reliably. The proposed controller has been compared to the P-PI position-velocity cascade controller commonly used in industry. The controller design, stability analysis and experimental results are discussed in the paper.