Robust nonlinear controller for underwater vehicle-manipulator systems

In this paper, a robust nonlinear controller is proposed for trajectory tracking of underwater vehicle-manipulator systems (UVMS). The controller is non-adaptive and of sliding mode type, and is designed based on the decentralized form of the dynamics of UVMS. It has the advantages of simplicity, robustness, precise performance, and ease of implementation. In order to demonstrate the effectiveness of the controller, several simulations using a five degrees of freedom UVMS are conducted. The results show that the proposed controller provides high performance of trajectory tracking in the presence of uncertainties about the dynamics and hydrodynamic disturbances