基于矢量场制导法和模型预测控制的船舶路径跟踪与避碰

Ship Path Following and Collision Avoidance Based on Vector Field Guidance Law and Model Predictive Control

为提高船舶路径跟踪和避碰效果,提出了一种基于矢量场制导法的模型预测控制方法.首先,采用矢量场制导算法将船舶的路径跟踪和船舶避碰问题转换为航向控制问题;然后,采用一阶Nomoto响应模型作为模型预测控制的动力学模型,考虑船舶的舵角输入受限问题,引入干扰观测器对模型误差项和环境扰动进行补偿,并应用Lyapunov理论证明了所设计的路径跟踪控制系统的稳定性;最后,设计了基于矢量场制导法的避碰策略,使船舶在路径跟踪的过程中同时完成自主避碰.仿真计算结果表明,开发的方法可以使船舶在波浪干扰作用下准确地跟踪目标路径并有效实现避碰.

A model predictive control(MPC)method based on the vector field guidance law is proposed to improve the effectiveness of path following and collision avoidance for ships.First,the path following and collision-avoidance problems are transformed into heading-control problems by the vector field guidance law.Then,the first-order Nomoto response model is adopted as the ship dynamic model for the model predictive control.Considering the input limitation of the rudder angle,the disturbance observer is introduced to compensate the model error and the environmental disturbances.The stability of the designed path following control system is verified by the Lyapunov theory.Finally,a collision avoidance strategy based on the vector field guidance law is designed to enable the ship to avoid collision autonomously in the process of path following.The simulation results indicate that the proposed methods can make the ship track the target path accurately and realize collision avoidance under the impacts of wave disturbances.