Control of residual vibrations in the space shuttle remote manipulator systems

摘要

This paper presents a control algorithm for eliminating flexible-structure residual vibrations. The so-called Pulse Active Damping (PAD) algorithm is developed and applied to the Space Shuttle Remote Manipulator System (RMS), which is probably the best existing example of a practical flexible manipulator. The proposed control algorithm is activated at the end of an RMS maneuver in order to damp out the end-effector vibrations in a fast manner. Basically, this is achieved by injecting torque pulses at the shoulder yaw and shoulder pitch joints so that associated cancelling oscillations are excited at the end-effector to "cancel" out the observed in-plane and out-of-plane end-effector vibrations. Robustness of this algorithm to uncertainty in the estimated natural frequency of the system is addressed and improved by a two-pulse control scheme. It is shown that large oscillations can be eliminated efficiently by PAD.