The cooperative motion planning of nonholonomic wheeled mobile manipulators （WMM） with kinematic redundaney in the constrained workspace was studied. A trajectory planning method combining the probabilistic planning and the solving of inverse kinematic equations was presented. First, the probabilistie planning method was used to determine the guide configurations; then the switching objective function was defined and the path of the end-effector was constructed based on these guide configurations ; finally, the inverse kinematic equations of the WMM were solved using the gradient projection method, and the obstacle avoidance trajectory for joints of the WMM was obtained. Simulation results were given to demonstrate the effectiveness of the proposed method.
