Impedance control with force signal compensation on space manipulator-assisted docking mission

Aiming at the task demands for space manipulator docking massive module, this paper studies the problem that docking mechanism cannot achieve docking due to the low precision of manipulator pose caused by factors such as flexibility of big wingspan manipulator, control error, mechanism error. First, this paper analyzes the docking mechanism in the docking mission, finds out that there is uniformity between the direction of force applied in the docking mechanism and the direction of centralization pose error of peg and hole decreased, and verifies the feasibility of impedance control algorithm. Then, because 6-D force sensor is installed far from docking mechanism and massive docking module leads to big inertia force, impedance control algorithm cannot get the force signals that reflect the actual situation of docking mechanism. For this matter, this paper proposes a 6-D force signals compensation algorithm to guarantee the correctness of impedance control calculation. Simulation experiment results indicate that impedance control algorithm with force signals compensation can both docking successfully and reducing the contact force effectively.