Dynamic coupling analysis of multi-arm space robot

Abstract

The base pose of a free-floating space robot can be disturbed by the motion of its manipulators. When a multi-arm space robot captures a space target, a closed-loop system will be formed, and the dynamic coupling between the base and manipulators or the target are more complex. This paper analyzes the dynamic coupling effect of the open-loop multi-arm space robot and the closed-loop system. According to the momentum conservation equation, the velocity correlation matrices between the base and the joints or end-effectors in the open-loop free-floating space robot, and those between the base and the joints or target in the closed-loop system are derived. On this basis, the dynamic coupling factors and coupling ellipsoids are proposed as two tools to measure the coupling degree. The coupling factors proposed in this paper are based on the singular values of the correlation matrices to expand the scope of application. The two tools are applied to analyze the coupling of a dual-arm space robot and its composite body with the captured target, where the influences of dynamic parameters, link lengths and joint variables are mainly studied.