Passivity Active Disturbance Rejection Collision Avoidance Compliant Control of Dual-arm Space Robot Capture Spacecraft

The collision avoidance compliant control of dual-arm space robot on-orbit capture of non-cooperative spacecraft is studied. For this reason, a spring class buffer device composed of Rotary Series Elastic Actuator (RSEA) is mounted between the joint motor and manipulator, which functions are as follows. First, the deformation of its buffer spring can absorb the impact energy of the contact and collision phase. Second, combining the reasonable collision avoidance compliant control scheme to ensure that the impact torque of the joints during motion stabilization phase can be limited to a safe range. The dynamic models of the open chain dual-arm space robot with RSEA and the spacecraft before capture are obtained by using the Lagrange approach and Newton-Euler method. Then, based on the impulse theorem, the geometrical and kinematic conditions of closed chain, the integrated dynamic model of the hybrid system is derived. Finally, considering the post-capture unstable closed-chain hybrid system which is caused by the impact effect, a passivity active disturbance rejection collision avoidance compliant control is proposed for the stabilization control. In addition, the joint torques are distributed by the minimum weighted norm theory to ensure the coordinated operation of the manipulators. Numerical simulation verifies the impact resistance performance of the buffer device and the effectiveness of the proposed strategy.