基于线性自抗扰控制的船舶航迹积分滑模控制器

Integral sliding-mode controller of ship tracking based on linear active disturbance rejection control

为解决欠驱动船舶航迹直线和曲线跟踪控制问题,选取能解决航向不稳定等非线性问题的Bech模型,借助双曲正切函数,构造期望艏向方程,将航迹控制问题转化为航向控制问题。设计3阶跟踪微分器,对期望艏向及其微分信号进行精确提取。采用变结构积分滑模面函数设计非线性误差反馈控制律,加快系统收敛速度,提出基于线性自抗扰控制(Linear Active Disturbance Rejection Control,LADRC)的船舶航迹积分滑模控制器。该控制器的线性扩张状态观测器对系统内外总扰动进行在线估计与实时补偿;引入Hurwitz多项式,减少需整定的参数。仿真结果表明,航迹收敛快速准确,无超调,对外界干扰具有较强的鲁棒性。控制器参数具有一定的普适性,故其适用范围广。

To solve the problem of the straight-line and curve-following control of the underactuated ship tracking,the Bech model which can solve the nonlinear problems such as heading instability is selected.The expected heading equation is constructed by the hyperbolic tangent function to turn the ship tracking control into the ship course control. A third-order tracking differentiator is structured to extract precisely the expected course and its derivative. To accelerate the system convergence rate,a variable structure integral sliding-mode surface function is introduced to design the nonlinear error feedback control law. An integral sliding-mode controller of ship tracking based on Linear Active Disturbance Rejection Control（ LADRC） is proposed. This controller can estimate and compensate the internal and external total disturbances in real time with the linear extended state observer; the Hurwitz polynomial is introduced to reduce the number of parameters to be set. The simulation results show that,the trajectory convergence is fast and accurate,without overshoot,and robust to external disturbances. The parameters of the control-ler are universal,so the controller has wide application range.