Collision-free motion planning algorithm for redundant space manipulators during coarse target capturing

The existing collision-free motion planning algorithms based on configuration space(C-Space) need to find the boundaries of C-space obstacles by solving C-space, which will cost much computation and memories for redundant manipulators with larger degrees of freedom(DOF). A novel algorithm was proposed to find the collision-free path in C-space by testing motion directions without solving C-space. This algorithm contained four sub-algorithms: the collision detection algorithm, the collision-free target configuration solver, the collision-free path-searching algorithm and the path-smoothing algorithm. Given the desired position and attitude of the end-effector, the target configuration solver calculated a collision-free target configuration. Then the path-searching algorithm found a collision-free path with C-space obstacle boundaries unknown. Finally, the path-smoothing algorithm smoothed the obtained path. To verify the effectiveness of the algorithm, two numerical examples were carried out. And the results indicate that the algorithm is efficient and can be used in fast motion planning for redundant manipulators in space applications.