Trajectory control of a flexible space manipulator utilizing a macro-micro architecture

A macro-micro manipulator system, which is composed of a long flexible-link manipulator as a macro manipulator and a relatively smaller rigid manipulator attached to the tip of the macro one as a micro manipulator, is employed to improve the motion precision of a flexible space manipulator. At the same time the macro-micro manipulator system preserves the capabilities of large work volume, high operation speed and low energy consumption of the flexible space manipulator. In this study, using the forward/inverse kinematics and a perturbation principle, an error compensation approach is proposed to eliminate as far as possible the endpoint errors of a flexible system through the fast and fine adjustment of the motion of the micro manipulator. A feedback model-based control scheme is proposed to realize the endpoint trajectory tracking of the flexible macro-micro manipulator system. Experimental results on a planar flexible 2-DOF macro/2-DOF micro manipulator system are presented herein to show the effectiveness of the proposed methods.