Abstract:

Focusing on the obstacle avoidance planning and control problem of a free floating space robot (FFSR), an FFSR obstacle avoidance planning-tracking integrated control method is proposed. Firstly, based on the obstacle pseudo-distance technique, the FFSR inverse geometric model is used to solve the pseudo-distance estimation at the desired position and attitude of the FFSR’s effector. Then, the FFSR obstacle avoidance trajectory is obtained by solving the nonlinear optimization problem. Secondly, based on discrete state dependent Riccati equation (DSDRE) control method, the FFSR obstacle avoidance planning-tracking integration control can be achieved by the combination of the global trajectory planning and the local online obstacle avoidance. Finally, the effectiveness of the proposed method is verified by the 6R space robot model. The simulation results show that the obstacle avoidance control of FFSR can be realized by the proposed method, which can effectively overcome the problem of the separation of the trajectory planning and control in the traditional FFSR control and improve the environmental adaptability of the FFSR.

Key words: Space robot, Integrated control, Obstacle avoidance planning, Discrete state dependent Riccati equation (DSDRE)