Abstract
Vibration suppression is important for high-precision motion control because positioning accuracy is an essential figure of merit for a servo system. The paper presents a vibration-suppression method that is based on adaptive optimal arbitrary-time-delay (AOAT) input shaping. First, analyzing a conventional optimal-arbitrary-time-delay (OAT) input shaper yields an OAT input shaper with five pulses that completely suppresses two-mode vibrations when the natural frequency and damping ratio are exactly known. Next, embedding an adaptive algorithm in the shaper gives an AOAT that handles unknown natural frequencies and damping ratios. Note that this shaper contains five pulses that have to be updated, but the delay times of the pulses are prescribed. Then, extending the symmetry of pulse amplitudes for zero damping ratio to a nonzero case reduces the number of pulses to three. A recursive-least-squares algorithm is devised to update these parameters. This shaper features the smallest number of parameters and high robust performance. Finally, comparisons with other input-shaping methods show the effectiveness and superiority of the developed method over others.
