Research On Expert System Of Course Control For An Air Cushion Vehicle

The amphibious air cushion vehicle (ACV) is a kind of high performance ship,which is lifted from ground or water surface by air cushion and propelled by aerial propellers.ACV has amphibiousness. There is little research results about ACV course control methods at home and abroad, in this paper this expert system is first introduced to the course control of ACV.A certain type ACV is the investigated subject in this paper, the rule-based expert system is designed, the researches have been developed as followings:Firstly, four degrees of freedom model are setup. The models of blocks are built. The motion function is formed based on the momentum and torch theorems.To convert to the moving coordinate system which is fit for the expression of hydrodynamic, ACV four degrees of freedom motion simulation model has completed.Secondly, the expert system of ACV course control based on Visual C++is designed. It is composed of knowledge base, inference engine, dynamic database and human-machine interface and other modules.According to the driving experience of operators and course-keeping experimental data to establish rule-based knowledge base, common reasoning mode and conflict resolution tactic of the expert system are introduced, the relationship between inference engine and knowledge base is studied, and reasoning mechanisml is discussed in detail, the friendly human-machine interface is designed and developed, the users can set the target parameters and the put of other parameters through human-machine interface, the final control results can be displayed in real time;the database management module is designed to store and manage data, and implement the communication between each module.The design of the underlying controller and the implementation of serial communication.The traditional PID control method is difficult to quickly achieve the desired setting angle, therefore, the adaptive backstepping controller with wind feedforward is designed as the underlying controller of the expert system of ACV course control.Finally, to verify the correctness of expert system of ACV course control, the simulation environment which is consistent with real environment in ACV navigation control process is built, use of the expert system of the ACV course control the course control tests in the interference of wind, the above tests verify the expert system's utility and reliability.