考虑扰动及模型不确定的无人船路径跟踪控制
2021-04-25栾天宇张玉峰张成伟许萌萌田甜
栾天宇 张玉峰 张成伟 许萌萌 田甜



摘要:针对外界扰动与模型不确定因素影响下的无人船路径跟踪控制问题,引入Serret-Frenet坐标系对无人船的路径跟踪问题进行数学描述,根据给定的期望跟踪路线与当前无人船的位置信息,利用李雅普诺夫直接法设计无人船航行速度与航向角度的期望值作为路径跟踪的虚拟控制律,通过设计滑模控制器实现对虚拟控制量的误差跟踪控制,通过设计切换函数避免无人船的控制量出现饱和或抖振现象,进而降低模型不确定及干扰对路径跟踪控制的影响。仿真实验表明,设计的控制器可在外界时变扰动与模型不确定的前提下完成对给定路线的理想跟踪。
关键词:无人船;路径跟踪;滑模控制;虚拟控制律;李雅普诺夫直接法
中图分类号:TP273 文献标识码:A
文章编号:1009-3044(2021)09-0223-04
开放科学(资源服务)标识码(OSID):
Path Following Control of USV Considering Disturbance and Model Uncertainty
LUAN Tian-yu, ZHANG Yu-feng, ZHANG Cheng-wei, XU Meng-meng, TIAN Tian
(Systems Engineering Research Institute, China State Shipbuilding Corporation Limited, Beijing 100036, China)
Abstract: Aiming at the problem of path following control of USV under the influence of external disturbance and model uncertainty, Serret-Frenet coordinate system is introduced to describe the path tracking problem of USV. According to the given expected tracking route and current position information of USV, the expected value of speed and heading angle of unmanned ship is designed by Lyapunov direct method as the virtual path tracking The pseudo control law realizes the error tracking control of the virtual control variables by designing the sliding mode controller. The switching function is designed to avoid the saturation or chattering of the control variables of the unmanned ship, so as to reduce the influence of model uncertainty and disturbance on the path tracking control. The simulation results show that the designed controller can complete the ideal tracking of a given route under the premise of external time-varying disturbance and model uncertainty.
Key words: USV; path following; sliding mode control; The pseudo control law; Lyapunov direct method
无人船(USV)运动控制技术是实现无人船智能、可靠运行的关键技术,要想使无人船可以按照既定的航线稳定、可靠地运行,就必须在运动控制技术上有所突破[1]。其中路径跟踪控制是无人船运动控制领域最为广泛的应用。通过设计合适的控制算法,在运行过程中对无人船的航速、航向进行控制,可使无人船沿着规划好的航线稳定航行。但在实际运行的过程中,无人船会受到风、浪、洋流等外部扰动的影响,而这些扰动的不确定性将导致无人船运动的非线性、时滞性以及大惯性;与此同时,无人船搭载的设备多少、无人船的实时航速会引起无人船运动过程中的参数摄动,参数的摄动使无人船的运动模型具有较大的不确定性[2];在外部的扰动以及模型的不确定性的影响下,无人船运动控制的鲁棒性会受到较大的影响。……
