Error-Constrained LOS Path Following of a Surface Vessel With Actuator Saturation and Faults
提出了一种误差约束视线路径跟踪控制方法，用于处理水面船舶在不确定性、干扰及执行器饱和与故障下的路径跟踪问题，通过新型障碍李雅普诺夫函数确保位置误差不越界。
This paper presents an error-constrained line-of-sight (ECLOS) path-following control method for a surface vessel subject to uncertainties, disturbances, and actuator saturation and faults. Based on a cascaded three degrees-of-freedom model of surface vessel, the backstepping technique is adopted as the main control framework. Error constraint of the vessel position is handled by integrating a novel tan-type barrier Lyapunov function. The proposed ECLOS method is in accordance with the classical line-of-sight method where no constraint is imposed. A nonlinear disturbance observer is developed to estimate the lumped disturbance that comprises the effects of parametric uncertainties, external environment disturbances, and actuator saturation and faults. It is proved that under the proposed control, the constrained requirements on the vessel position error are never violated and all closed-loop signals are uniformly ultimately bounded, regardless of fully actuated or under-actuated control configuration. Simulation results and comparisons illustrate the effectiveness and advantages of the proposed ECLOS path-following method.