Robust Propulsion Control for a Class of X-rudder Autonomous Underwater Vehicle

In this paper, a robust propulsion control design for a class of X-rudder Autonomous underwater vehicles (AUVs) is proposed. Two cases for nonlinear equations of motion of X-rudder AUV in heading and longitudinal planes are considered in this work. In the first case, a state feedback controller based on traditional nonlinear Sliding Mode Control (SMC) is designed which stabilizes the states of the closed-loop system and tracks a constant (desired) steering and pitch angle. Then, for the same case, in the presence of parametric variations, a robust stabilization control based on Integral Sliding Mode Control (ISMC) is evaluated. Moreover, a proper X-rudder angles allocation method is designed which converts control inputs into respective rudders commands. Furthermore, the performance of the proposed controllers is evaluated and demonstrated with the help of numerical simulations.