Abstract: To avoid dynamic singularities, a Cartesian trajectory planning method for a free-floating space robot is developed in this paper. Combining the trapezoidal programming and sine functions, the position and attitude of the end-effector are parameterized. Based on the damped least-squares (DLS), this paper proposes a method to determine whether the singularities occur during the movement of the manipulators. It can guarantee that the space robot cannot meet the singularities with the method. Moreover, considering the base attitude disturbance and the moving time, a cost function is obtained. Therefore, the trajectory planning issue is transferred to an optimization issue. The chaos particle swarm optimization (CPSO) algorithm for mixed integer programming is implemented to find the optimal solution. Compared with particle swarm optimization (PSO), it can improve the premature. The numerical simulations have demonstrated that the designed method can avoid dynamic singularities, and minimize the base attitude disturbance and the moving time effectively.

Key words: Space robot, Trajectory planning, Dynamic singularities, Base attitude disturbance, Moving time, Chaos particle swarm optimization (CPSO)