Cascaded Design for Robust Path Following Control of an Underactuatd Surface Vehicle

This paper concerns the cascaded design for path-following control of an underactuated surface vehicle. Different from the traditional way in construction of the Lyapunov function for the overall system iteratively. By constructing the equivalent control for the kinematics, the path-following error dynamics can be transformed into a novel cascaded form, which can be viewed as a self-stable nominal system that is perturbed by a perturbing system through the interconnection and remove the persistent excitation condition constraint on yaw angle. The control of the overall system can be equivalent to stabilization of the perturbing system and analysis the properties of the interconnection function. Since the states in the perturbing system can be actuated directly, the sliding mode control (SMC) is employed to stabilize the perturbing system in the present of model uncertainties, the verification for the stability of the cascaded system is carried out the make sure the sufficient conditions are satisfied to guarantee the global asymptotic stable for all signals in the closed-loop. Finally, the simulation results are provided to illustrate the effectiveness of the proposed method.