Trajectory Tracking Control for Nonholonomic Wheeled Mobile Robots with External Disturbances and Parameter Uncertainties

Aiming at the trajectory tracking problem of nonholonomic wheeled mobile robots (WMR) with bounded external disturbances and parameter uncertainties, a dual-loop attitude tracking robust controller is proposed for WMR. Firstly, a kinematic controller is designed to generate the virtual velocity based on the kinematic error model. Secondly, the sliding mode control with a modified reaching law is adopted to ensure the actual velocity can converge to the virtual velocity in finite time based on the dynamic model. Finally, the stability of the controller is verified through the Lyapunov function. Numerical simulation shows the robustness and effectiveness of the proposed dual-loop tracking controller.