부산대학교 도서관

In this article, a prescribed time output feedback 3-D stabilization control scheme is proposed for unmanned underwater vehicles. Considering the problem of unmeasurable velocities, unknown hydrodynamic parameters, and external underwater perturbations, we construct a prescribed time extended state observer (PTESO) for the unmanned underwater vehicles based on a time-varying scaling function that can estimate the linear and angular velocities as well as unknown nonlinearities within a preset time. Then, a novel prescribed time output feedback controller is developed for the unmanned underwater vehicles with the aid of PTESO, which exhibits a simplified structure and allows for advance specification of the prescribed time. By using Lyapunov stability theory, it is strictly proven that the stabilization error converges to zero within a prescribed time. Finally, an experimental test is carried out on an open-frame unmanned underwater vehicle to verify the effectiveness of the proposed scheme.