Hassan Sayyaadi - Associate Professor, Sharif University of Technology/Department of Mechanical Engineering;
Abbas Ghasemzade Ahrami - Msc Student, Sharif University of Technology/Department of Mechanical Engineering;

This paper is concerned with the design of a non-linear controller for autonomous supply vessel. An integrator back stepping and feedback linearization control laws are presented. Feedback linearization is easily applicable to ship, since this model basically is nonlinear system. Back stepping is a design methodology for construction of feedback control law through a recursive construction of a lyapunov function. When applying the back stepping design methodology, more design flexibility is obtained. Hence, additional robustness is obtained, which is important in industrial control systems since cancellation of all nonlinearities requires precise models that are difficult to obtain in practice. The controller's laws are developed by using Genetic Algorithm method to obtain the optimized gains. This approach avoids time consuming for assess controller gains by the try and error methods. Position controls of the vessel are guaranteed and the numerical results are provided appropriately. Simulation results are carried out by using MATLAB on the controllers' effects and circumstances

Ship motion, Non-linear control, Feedback linearization, Back stepping, Surface vessel, Genetic Algorithm