Adaptive steering control law for nonlinear maneuvering models with input magnitude and rate limits

Abstract An adaptive steering control law is designed for uncertain nonlinear maneuvering systems with limits on the rudder angle and the steering speed. The constraints on the magnitude and the rate of rudder angle are treated by introducing auxiliary variables and systems. The control input and the parameter update law are designed following the adaptive backstepping method. It is shown that all signals in the controlled system are bounded. In addition, the bound for the tracking error is obtained in terms of the signal saturation. By numerical experiments of the course change control, the control performance of the proposed control law was verified in the case where shaped target signals are applied. This indicates the feasibility of an adaptive nonlinear tracking control law considering the limits on rudder angle and steering speed, which can perform the course change control for various target heading angles without shaping the target signal.