Optimal grasping pose for dual-arm space robot cooperative manipulation based on global manipulability

This paper presents an approach to determine optimal grasping poses for dual-arm space robot cooperatively grasping an uncooperative satellite. Aiming at better manipulating the satellite after capture, it is necessary to plan properly grasping poses on the satellite for dual-arm end-effectors to maximize the manipulability of space robot. In this paper, global manipulability based on capability map is applied as the quality index to seek optimal grasping poses. First, the technique to generate cooperative workspace for a closed chain system is introduced fusing the workspace of each single-arm with self-collision avoidance. Second, several general manipulability indices, such as dexterity, manipulability measure and task compatibility, are extended to the entire cooperative workspace to construct capability maps. Next, global manipulability is evaluated for dual-arm space robot cooperative manipulation based on the capability maps. Following this, the optimal grasping poses among all feasible grasping poses on the satellite are obtained by the global manipulability. Finally, a simulation study is carried out to verify the feasibility of the proposed approach based on a redundant dual-arm space robotic system.