Contact force minimization strategy for space floating manipulator

Abstract

When a space manipulator captures an object in orbit, the excess contact force during collision causes the uncontrollable vibration of the manipulator and object. To devise a strategy for reducing this vibration, this paper leverages the multiple configurations of a redundant manipulator and seeks to identify the optimal configuration and contact direction based on the effective mass method. In this paper, a collision model is first established between the end effector and the object based on the continuous contact force method. Then, the peak force, maximum compression, and contact duration between the two bodies during the collision are obtained. For a certain task, the magnitude of the contact force only depends on the effective mass of the space manipulator. Hence, the mapping relationship between the effective mass and the configuration and contact direction of the space manipulator is established, and an ellipsoid is used to describe it. Accordingly, a contact force minimization strategy is designed. The optimal manipulator configuration and collision direction corresponding to the minimum contact force are obtained, and the correctness and effectiveness of the calculations are verified using MATLAB and Adams simulations.