An adaptive control design for dynamic positioning (DP) of unmanned surface vessels is addressed in this study. The control design is realized by taking actuator dynamics into account for obtaining a DP system where distribution of generalized forces to the actuators is considered. Owing to this approach DP system is made suitable for unmanned surface vessels having actuators equal to or more than number of generalized forces. All parameters of the surface vessel's body and actuator dynamics except thrust configuration matrix are assumed to be uncertain for the proposed control design. The parametric uncertainties are coped with adaptive compensation rules while the designed controller is equipped with a term that provides the robustness of the designed controller against disturbances including internal and external unmodeled effects. Backstepping control design approach is preferred for the control design process by considering the appropriateness of this approach for the system model of unmanned surface vessels include actuator dynamics. Theoretical proof of the designed controller is realized via Lyapunov–based arguments. Simulation studies where the efficiency of the designed controller is observed for both of aforementioned cases are conducted for the performance demonstration of the designed controller.
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