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 (AUKF) 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 AUKF and the controller.