Digital Adaptive Control of Space Manipulator : 2nd Report, Validity of Simplifying a Generalized Jacobian Matrix

Abstract

This paper deals with a digital adaptive control method for a manipulator mounted on a space robot after it captures an unknown object. Most of the previous control methods are based on the supposition that all physical parameters of the space robot system are known. However, if the end-effector catches an unknown object, the physical parameters of the robot are changed, and the control performance deteriorates. In this work, we propose two types of digital adaptive control algorithm in which a discretized kinematic equation is used. One is for discrete time Resolved Motion Rate Control (RMRC) with adaptive control and state feedback, and the other is for discrete time RMRC using a simplified Generalized Jacobian Matrix (GJM) with adaptive control and state feedback. Experimental results show that the control performance can be enhanced by use of the two proposed methods, and we conclude that simplifying a GJM is valid for the adaptive control system proposed in this paper.