Pre-impact Trajectory Planning of Nonredundant Free-Floating Space Manipulator

The joint motion of the space manipulator and the collision between the end-effector and target may cause the attitude disturbance of the base. To minimize these two kinds of disturbances simultaneously, a pre-impact trajectory planning method for a nonredundant Free-Floating Space Manipulator (FFSM) system is proposed. Firstly, using the momentum conservation and nonholonomic characteristics, a transitional state between the initial state and the final capture state is added. This state can achieve the correct capture pose of the end-effector. Thereafter, the particle swarm optimization (PSO) algorithm is employed to optimize the transitional state and parameterized joint trajectory to minimize the base disturbance caused by joint motion and collision pulses. Finally, the proposed method is applied to a 6-DOF FFSM system. The results show that this method can realize the optimal pre-impact trajectory planning, and verify its effectiveness.