Filtered Back-Stepping Based Integrated Control for Rudder and Fin

A rudder and fin integrated control method was employed in this paper to keep the course and reduce the rolling of a ship in ocean waves. To deal with the characteristics of multi-variable and non-linearity in the 4-DOF ship model, a filtered back-stepping controller was proposed to stabilize the yaw and roll. First, a filter anti-tangent with nonlinear was used to estimate the virtual middle control. Second, a genetic algorithm based numerical iterative method was adopted to calculate the final control variables namely the rudder angle and fin angle. At last, a multipurpose vessel was employed to invest the proposed control strategy by numerical simulation. The simulation results shown that the proposed control strategy was suitable with a satisfying performance in the course keeping and roll stabilization.