Research And Development Of Automatic Driving System Based On Luzhong 500A Tractor

The "14th Five-Year Plan for Promoting Agricultural and Rural Modernization" pointed out that the work of "agriculture,rural areas and farmers" is the top priority of building a socialist modern country in an all-round way.The current global competition in science and technology is unprecedentedly fierce,and it is urgent to strengthen agricultural technology and equipment support.As an important scientific research technology in the field of "agricultural precision operation and informatization",automatic driving technology is of great significance to the modernization of agricultural science and technology,and meets the development needs of my country’s modern agriculture.Therefore,this paper takes the Luzhong 500 A tractor as the research object,realizes the automatic driving and path tracking control of the tractor,and carries out the following research work:(1)In order to realize the automatic steering,shifting and braking functions of the tractor,the mechanical transformation design of the executive mechanism(steering wheel,shift handle,clutch pedal,brake pedal,accelerator pedal)of Luzhong 500 A tractor was carried out,and the executive mechanism was introduced in detail How it works after the retrofit design is complete.(2)Design the overall scheme of the tractor automatic driving control system.Firstly,select the hardware of the control circuit,navigation system,and executive mechanism.Design,introduces the starting module,steering module,shift module and braking module of the automatic driving control system in the form of control flow chart,and finally realizes the operation of the tractor automatic driving control system.(3)Combined with the tractor’s operating environment and operating requirements,a simplified kinematics model and dynamics model were established and the coordinates were transformed.Based on the magic formula tire model proposed by Pacejka,the tire model was built in the Carsim simulation software to design a path tracking controller.Theoretical preparation is provided.(4)Based on the path tracking error dynamics model,a feed-forward control + LQR(GA+FFC+LQR)controller based on genetic algorithm improvement is designed,and a joint simulation platform is built by Carsim/Simulink software and the simulation test is carried out.The simulation results show that it is compatible with LQR control Compared with controller and GA+LQR controller,the designed GA+FFC+LQR controller has obvious improvement in control accuracy and better stability when tracking the planned path.(5)Based on the Luzhong 500 A tractor,the automatic driving test platform was built and the field test was carried out.The field test results showed that the modified Luzhong 500 A tractor met the requirements of automatic driving.The control accuracy is good,and it can accurately track the planned path,which meets the needs of tractor field operations.