Adaptive UKF Based Tracking Control for Unmanned Trimaran Vehicles

Trimaran which is constructed by a main centre hull and two small outer hulls has clear advantages over the normal single-hull surface vehicle. Main difficulty in the control design of Unmanned Trimaran Vehicles(UTV) is how to reject the hydrodynamic uncertainty and environmental disturbances. In this paper, a control scheme involving online parameter/disturbance estimation is proposed in order to reject the hydrodynamic uncertainty and environmental disturbances. Within the control structure, a novel adaptive Unscented Kalman Filter (A UKF) is constructed based on the master-slave structure. This intends to release the dependence of normal UKF on the priori knowledge of noise distribution, which is difficult to obtain in real systems. An AUKF-enhanced exponential tracking controller is further developed to realize the robustness with respect to the time-varying parameters and disturbances. Simulations conducted on the dynamics of a home-developed UTV test-bed demonstrate the performance of both the A UKF and the controller.