Research And Application Of Automatic Navigation And Working Platform Of High Ground Clearance Sprayer

Intelligent agricultural machinery and equipment is one of the ten key research areas of"Made in China 2025",and the automatic navigation technology of agricultural machinery is a key issue in the research of intelligent agricultural machinery and equipment.High-clearance sprayer is an important plant protection machinery,and the study of automatic navigation and operation platform of high-clearance sprayer is beneficial to improve the efficiency and quality of spraying.However,the existing automatic navigation system does not consider the complex working environment of the sprayer with high ground clearance,which reduces the path tracking accuracy,and the high center of gravity of the vehicle leads to the problem of rollover during path tracking.This paper takes the automatic navigation and operation platform of the high ground clearance sprayer as the research object,studies the control method of automatic navigation and operation,and solves the problems of poor software and hardware integration and collaborative control,low path tracking accuracy and poor anti-interference ability in complex environments,and path tracking.The problem that the body is easy to roll over has important theoretical significance and application value for improving the stability and accuracy of automatic navigation and operation control of high-clearance sprayers,The main research contents are as follows:At present,the main controller of the automatic navigation system is not rich in peripheral interfaces,the system control logic is unstable,the positioning accuracy is low,the stepless speed regulation and braking ability are poor,the long-distance communication and data transmission are unstable,the automatic steering accuracy is low and the response is slow.,inaccurate wheel steering angle measurement,poor cooperative control effect of automatic navigation and operation system,etc.,design a set of high ground clearance sprayer composed of main controller,positioning system,walking control system,communication system,automatic steering system and operation system The automatic navigation and operation platform realizes the coordinated control of the positioning,steering,speed regulation,braking,communication,boom movement and other tasks of the high ground clearance sprayer during the automatic navigation process,and improves the stability of the system and the integrity and accuracy of data transmission.speed,speed of stepless speed regulation and braking,automatic steering and speed and precision of boom action.Aiming at the problems of unsystematic path planning scheme and large headland turning space,a straight-line path,linear array and headland automatic turning scheme are designed,and a path planning method is systematically established to effectively reduce the headland automatic turning space.A correction method is proposed for the positioning roll deviation,which can effectively correct the positioning deviation caused by the roll and ensure the accuracy of the positioning data.Aiming at the problems that the deviation affects the path tracking accuracy,low path tracking accuracy and poor anti-interference performance in complex environments,a path deviation calculation method,a fusion method of lateral deviation and heading deviation,and a path tracking control algorithm based on improved fuzzy PID are proposed.The algorithm is verified in Matlab/Simulink.The results show that the average deviation is 0.0221m when the initial deviation from the planned path is 0.3156m,the average deviation is 0.0546m when the initial deviation from the planned path is-0.5906m,and the average deviation is 0.0294m under external interference.Since the average deviation of the PID algorithm is significantly reduced,it has good path tracking accuracy and antiinterference ability.Aiming at the problem that the vehicle body is easy to roll over during the automatic steering process,an automatic steering algorithm based on anti-rollover and PD is proposed to effectively improve the vehicle body stability and steering performance during path tracking.Build a high-clearance sprayer automatic navigation and operation test platform,and test and verify the steering performance,positioning accuracy,operating system performance,linear path tracking accuracy,body roll,and automatic turning plan on the ground.The results show that the wheels turn quickly;the correlation coefficients of positioning data fitting at different speeds are all higher than 0.98,which meets the needs of positioning accuracy;the operation system and the automatic navigation function are coordinated and the boom moves quickly,effectively protecting the mechanical structure;Straight line tracking at a speed of 0.8m/s,when the initial deviation from the planned path is 0.2288m,the quick adjustment time is 2.6s,the average deviation is 0.0565m,the maximum body roll angle is 3.2°,and when the initial deviation from the planned path is-0.5399m,the quick adjustment The time is 4.5s,the average deviation is 0.0810m,the maximum body roll angle is 4.5°,the path tracking accuracy is good,and the body stability is good;the high clearance sprayer completes the U-turn at the headland according to the designed automatic turning plan and tracks the next path.The designed software,hardware and various functions of the automatic navigation and operation platform work well and basically meet the working requirements of the high ground clearance sprayer.