Research On Track Keeping Control Method Of Air Cushion Vehicle

Air cushion vehicle(ACV)is used widely as a kind of high performance vessel both in the civilian and military.The ACV can be completely out of the surface of water relying on the support of the air static pressure.Therefore,ACV has the characteristics of high speed,amphibious,good seakeeping etc.However,the characteristic that ACV sails above the surface of the water leads to the lack of the underwater gear,and there will be skid,drift,capsizing danger when there is a large steering angle rotation.ACV is sensitive to the external disturbances,wind disturbance will cause the hull side leakage,heeling,obsessed and other dangerous situations.These problems show that ACV has poor maneuverability and is hard to control.For solving these problems,experts at home and abroad focus on doing research on integrated control system to realize automatic sailing control of ACV and reduce burden of sailors and enhance the safety of navigation.In order to let ACV arrive at the destination safely and fast and save energies,this paper researches on trajectory control method of ACV.This paper uses a certain ACV model as research object to realize trajectory control of ACV by the indirect control,and the primary work is as follow:Firstly,modules are builtbased on the data of the experimentsin a certain type of ACV.Each modelis deduced by Newton's law of force,so a four-DOF motion mathematical model of ACV is established.Secondly,we finish the simulation verification of motion mathematical model and the handling characteristics analysis of the direct sailing,rotation,and Z-shaped motion with the conditions of all kinds of wind.the simulations of sailing charateristics conform to reality.Thirdly,the theories of model free adaptive control and sliding mode control are introduced.The track keeping guiding controller is designed with model free adaptive control theory and handing controller is designed with sliding mode control theory,and achieved the simulationcomparison with the track keeping guiding controller is designed by PID algorithm.Finally,in order to improve the accuracy of track keeping control and parametric performance in the control process,tracking differentiator is used in the model free adaptive track keeping guiding controller,and the handing controller is designed with disturbance observer and non-singular terminal sliding mode control.The simulation show that the improved track keeping controller is of more good effect than traditional sliding mode controller.