基于LOS导航的欠驱动船舶滑模控制

Sliding-mode control of underactuated ship based on LOS guidance

考虑存在外界随机海浪干扰和模型参数不确定的欠驱动船舶非线性运动模型,提出一种基于可视距(LOS)导航的滑模控制器。通过设计切换面克服参数不确定以及波浪扰动对反馈控制带来的困难,并在滑模控制的基础上引入低通滤波器,消除因扰动和滑模切换面自身引起的横漂速度和艏摇速度的高频振荡,实现速度的光滑控制。利用李亚普诺夫理论对控制算法的稳定性进行证明,并进行一艘单体船的数值仿真实验。研究结果表明:所设计的控制器是有效的,且具有良好的鲁棒性。

Considering the nonlinear mathematic model of underactuated ship with external random wave disturbance and uncertain parameters, a sliding-mode controller based on the line of sight（LOS） guidance was proposed. The difficulty in feedback control resulted in parameters uncertainty and wave disturb was solved by designing the switch surface. Under the sliding-mode condition, a low-pass filter was introduced to the controller, thus, the high-frequency oscillation of sway velocity and yaw rate caused by disturbance and switch surface itself were eliminated, and the smooth control of velocities was achieved. The control stability was proved by using Lyapunuov theory. The result shows the controller is effective and is of good robustness.