In this paper, a smooth robust control method is developed to stabilize asymptotically ship roll, of which fins are used to provide the active moment again that caused by waves. The control scheme is able to derive the roll angle, roll rate and roll acceleration to converge asymptotically to zero in a finite time while wave disturbances act continuously on the ship. The useful nonlinearities of restoring forces and damping are taken into account to provide a simple and effective controller. The stability analysis is based on Barbashin and Krasovkii theorem and mean valued theorem. The Lyapunov function like puts penalty on roll angle, roll rate and roll acceleration.
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