Performance-guaranteed control of an autonomous underwater vehicle subject to time-varying disturbances

This paper present a control design technique of asymptotic trajectory tracking with guaranteed transient performance for an autonomous underwater vehicle (AUV) subject to external time-varying disturbances. To achieve the asymptotic convergence of output tracking errors, the robust integral of the sign of the error (RISE) feedback method is employed to compensate for the effect of the external disturbances. In the previous RISE-based control scheme, the upper bounds of the external disturbances and their derivatives are often required to be known a priori, while this requirement is relaxed by adaptive tuning gain of the error sign term. To further provide the transient performance of the tracking errors, the prescribed performance control technique is introduced to guarantee that the convergence rate of the tracking error is faster than a prescribed speed and the overshoot of the tracking error is less than a predefined value. Based on backstepping procedure, prescribed performance control, and Lyapunov synthesis, a RISE-based controller is designed to achieve asymptotic convergence of the tracking errors with guaranteed prescribed performance. The effectiveness of the proposed control strategy is demonstrated through numerical simulation.