Performance comparison of backstepping-based adaptive controllers for marine surface vessels

This paper deals with the design and evaluation of three controllers based on backstepping and different adaptive control schemes, which are applied to the motion control of a nonlinear 3 degrees-of-freedom model of a marine surface vessel. The goal is to make a comparative analysis of the controllers in order to find out which one has the best performance. The considered controllers are: Adaptive backstepping, backstepping with composite concurrent learning and backstepping with cascaded concurrent learning. Numerical simulations are performed for target tracking along an elliptic path, with uncertain vessel model parameters. Motion control performance is evaluated by performance metrics such as IAE and a novel metric named IAEW-WT which combines control accuracy, energy use and actuator wear and tear in one single metric.