Abstract: The idea of strict dissipation is introduced into the straight-line tracking control system for underactuated ships.The robust dissipative control for the system with bounded exogenous disturbances is studied. Based on the dissipative inequality, a globally robust state feedback controller is developed so that the resulting closed-loop system is both strictly dissipative and asymptotically stable.Furthermore, the proposed algorithm is able to enable an underactuated ship to be globally and ultimately stabilized on a prescribed straight line under external disturbances.Numerical simulation results are presented to validate the effectiveness and transient performance of the proposed controller.

Key words: underactuated vessels, straight-line trajectory, robust dissipative control, backstepping design