Global output feedback control of dynamically positioned surface vessels: an adaptive control approach

In this paper, we consider the output feedback control problem for dynamically positioned surface vessels when uncertainties related to the system parameters are present. Specifically, by applying Lyapunov techniques, we design a nonlinear model based adaptive output feedback controller that achieves global asymptotic tracking and compensates for the parametric uncertainties associated with nonlinear ship dynamics despite the lack of velocity measurements. Simulation results are included to illustrate the performance of the proposed control law