基于滑模预测控制的水面无人船轨迹跟踪研究

Trajectory Tracking of Unmanned Surface Vessels Based on Sliding Mode Predictive Control

针对全驱动无人船(USV)的轨迹跟踪问题,提出了一种模型预测控制和积分滑模控制相结合的双层控制方法。首先,针对无人船系统的运动学模型,设计模型预测控制器(MPC)根据期望轨迹得到满足约束条件的期望速度信号;针对动力学模型,设计积分滑模控制器(ISMC)使得系统在外界干扰存在的情况下,实现对期望信号的跟踪,提高了系统的鲁棒性;设计非线性干扰观测器对外界干扰进行估计,并在控制律的设计过程中进行补偿;最后,采用李雅普诺夫方法证明了系统的稳定性。数值仿真证明了两者的结合可以有效地实现全驱动无人船的轨迹跟踪。

To solve the problem of trajectory tracking of fully-actuated Unmanned Surface Vessels(USV),a dual-layer control method combining Model Predictive Control(MPC)with Integral Sliding Mode Control(ISMC)is proposed.Firstly,as for the kinematics model of the USV system,a model predictive controller is designed to obtain the desired velocity signal satisfying the constraints according to the desired trajectory.As for the dynamics model,an integral sliding mode controller is designed to track the desired signal in the presence of external disturbances,which improves the robustness of the system.A nonlinear disturbance observer is designed to estimate the external disturbance and compensate for the external disturbance during the design of the control law.Finally,the stability of the system is proved by the Lyapunov method.Numerical simulation proves that the combination of the two can effectively achieve the trajectory tracking of the fully-actuated USV.