Research On Path Tracking And Control Method Of Multi-control-surface Polar Air Cushion Vehicle

China has an extremely urgent demand for the research and exploration of the Arctic region.It is of great significance to develop a polar air cushion vehicle with ice breaking/transportation capacity which can be applied in the complex polar environment for scientific investigation,material transportation and personnel transfer.The polar air cushion vehicle is different from the ordinary surface hovercraft.The former is mainly used in polar multiple-interface terrain,and it is difficult to control,especially when sailing on the snow-covered ice layer.The friction resistance between air cushion and ice surface is very small,so "sideslip" and "tail flick" could easily happen and it is very risky for the vehicle.In this paper,the polar air cushion vehicle is taken as the research object,and the motion and control strategy of the air cushion vehicle on the polar snow-covered ice layer are mainly studied by means of theory,simulation and experiment.First,according to the motion mechanism of the air cushion vehicle in the polar region,a three degree-of-freedom mathematical model of polar air cushion vehicle on the snow-covered ice layer is established.The kinematic and dynamic model of air cushion vehicle established on the basis of northeast coordinate system and local coordinate system,the ice load model and wind load model established according to the experiment data and empirical formula,as well as the propulsion and control system model established according to the installation parameters and structural characteristics of the propulsion and control system.The simulation results show that the model is accurate and reasonable.Second,according to the multiple interface terrain conditions in polar region,the manual control strategy of air cushion vehicle under various working conditions is studied.It mainly includes: straight line navigation,braking and small-angle turning performance in forward mode;straight line navigation,braking and small-angle turning performance in backward mode;large-angle turning performance in low-speed turning mode;and zero speed turning performance in in-situ turning mode.The motion simulation analysis is carried out in different modes,and the motion and control characteristics of the air cushion vehicle on the snowcovered ice layer are studied.Next,the automatic control strategy of polar air cushion vehicle is studied.The following work.First,according to the motion characteristics and problems of air cushion vehicle in polar region,the control requirements on the polar snow-covered ice layer are proposed.Then,a motion controller considering the characteristics of multiple control surfaces is designed,and the motion control system of polar air cushion vehicle is built.Furthermore,the linear path tracking method of air cushion vehicle is designed,and an automatic/hybrid control strategy of polar air cushion vehicle is proposed.The simulation results show that the research realizes the speed and heading control of the air cushion vehicle,and realizes the real-time coordinated control of multiple control surfaces.Besides,the study successfully suppresses the dangerous sideslip movement,and solves the control problem of the air cushion vehicle in polar area.Finally,QT creator is used to develop a motion and driving simulator of polar air cushion vehicle.The simulator includes the control platform of hardware and simulation platform for display and control.The software part integrates the above mentioned functions to display the working state of air cushion vehicle in real time.The hardware equipment can simulate the actual operation through the joystick.A set of motion simulator with complete functions is constructed.The function of the simulator is verified by the simulation of multi-segment linear path tracking.