A new sliding mode variable structure controller is proposed. First, aiming at improving the convergence speed, a new nonlinear sliding mode surface is proposed. Then, the initial error speed is designed to make the initial state of the system to be just on the sliding mode surface which is to impair the chattering and improve the robustness of the controller. Finally, a mobile manipulator with two arms is taken as an example to simulate the trajectory tracking with the proposed controller. It is found that system shows high convergence speed and strong robustness against disturbance. The chattering is also impaired greatly.