Zero-Disturbance Control of Free-Floating Space Manipulators Using Integral-Type Sliding Mode Control

Abstract

A free-floating space manipulator is an underactuated system, of which the spacecraft is permitted to rotate freely in response to the manipulator motions. The dynamic coupling property between the spacecraft and the manipulator makes motion control of such systems a significant challenge. In the paper, a zero-disturbance control method for free-floating space manipulators operating in task space is presented. An explicit direct relationship between the spacecraft attitude quaternions and the manipulator joint variables is established using nonholonomic constraints of the angular momentum conservation. By this means the kinematic redundancy of the system is used to adjust the spacecraft attitude. An integral-type sliding mode controller with adaptive switching gains is developed for coordinated motion control of the spacecraft and the manipulator. Simulations on three-link planar model show that the spacecraft remains undisturbed during the whole process of manipulations, which confirms the effectiveness of the proposed method.

Path Planning for a Space-Based Manipulator System Based on Quantum Genetic Algorithm

“…In other words, for the same joint configuration, different joint paths correspond to different poses. The authors of [4,5] studied the course of the development and the status of nonholonomic systems as well as their principles of dynamics and control methods. Rathee and Pathak [6] present path planning of dual arm free flying space robot using smooth functions of time.…”