This paper presents an adaptive robust tracking control method for a mobile manipulator during trajectory tracking. The parameters of the mobile manipulator dynamics are updated online. The design of the controller is based on two cascaded subsystems: a minimum norm kinematic controller with command saturation, and an adaptive controller that compensates the dynamics of the mobile manipulator system. Robot commands are defined in terms of reference velocities. Stability and robustness are proved by using Lyapunov's method. Experimental results show a good performance of the proposed controller as proved by the theoretical design.