Method for nonlinear L 2 control of ships: course-changing and path tracking

Abstract In this work a design procedure for course-changing control and path tracking control is presented, which is based on nonlinear L 2 control theory. The proposed method uses a nonlinear model of the ship and obtains a non-linear suboptimal H ∞ controller (state feedback version or state estimated approach with a non-linear observer). A symbolic computation environment is necessary to carry out the steps of the control system methodology; which has been implemented using Maple and Matlab programs. Software environment and simulation results are presented for course-changing and path tracking control.