Research On Driving Anti-skid Control Technology Of Paddy Field Self-propelled Sprayer

The self-propelled sprayer has advantages of outstanding efficiency and good spraying quality,so it is suitable for large area operation.But the wheel skidding often happens because of complex paddy field environment,low adhesion coefficient,different depth of mud,etc.At present,those self-propelled sprayers lack the function of automatic detection and independent control to the wheel slip condition,which seriously affects the working efficiency.In order to solve these problems,the operating condition detection and sliding control system of paddy field self-propelled sprayer was developed,and built a hydraulic test bench to carry out the driving anti-slip experiment with single-wheel.The main contents of the study are as follows:1.The dynamic model of thirteen degrees of freedom for paddy field self-propelled sprayer is established.The tire model and dynamic model of the vehicle and wheel are established by modular modeling method.Complete the simulation analysis of some typical working conditions,such as the change of adhesion coefficient,the change in topography,accelerate and decelerate on a straight line,the forward wheel steering angle changed with step input and sine wave input.Verify the correctness of the model,based on the dynamic response of the vehicle.2.Research on pavement recognizer based on T-S Fuzzy Model.Using ?—s relation curve of six typical pavements described by Burckhardt tire model as sample database.The degree of similarity between the current adhesion coefficient of the self-propelled sprayer and that of each typical pavement in the database under the same slip rate is obtained to calculate the peak adhesion coefficient and the optimum slip rate of the current pavement by using the weighted average method.In this paper,the control scheme and risk early warning method for roller skidding and sideslip are put forward.3.Design the Fuzzy-PID controller in valve controlled hydraulic motor system.The Fuzzy-PID controller is used to simulate the speed and slip rate of the motor,based on the mathematical model of valve controlled hydraulic motor system.4.Design of the driving anti-skid control system.The system mainly includes the sensors such as rotation speed,steering angle,vehicle speed and attitude of the measuring unit,the on-board computer and industrial control board of the control unit,the solenoid valve amplifier and the solenoid value group of the executive unit,and so on.Collect the key parameters such as rotation speed,steering angle,vehicle speed and attitude of the paddy field self-propelled sprayer to drive by anti-slip Fuzzy-PID control.5.Build valve control hydraulic test bench and carry out the experimental study on the control of single wheel slip.The magnetic powder brake is used to control the load torque to simulate the wheel slip caused by the reduction of the adhesion coefficient and carry out the test of driving anti-slip control.The test results show that the system can effectively estimate the peak adhesion coefficient and the optimum slip rate on unknown road surface.And the system can reduce the wheel slip effectively and increase the utilization adhesion coefficient when the wheel slip occurs.It meets the need to improve the anti-slip ability of the sprayer.