Research On Intelligent Control System Of Unmanned Boom Sprayer In Paddy Field

With the promotion of precision agriculture in China,the level of agricultural machinery intelligence has gradually improved.Autonomous navigation technology and remote control technology have become the key technologies for reducing labor intensity and improving work efficiency and quality in agriculture.Especially in rural areas,China has the most aging population structure.In severe areas,the labor force is seriously inadequate,and the implementation of the rural revitalization strategy needs to rely on the development of key technologies for agricultural equipment.In this paper,a set of intelligent control system for paddy field application machine is designed by integrating autonomous navigation technology and remote control technology,and the intelligent control system is integrated and tested.The specific work and results are as follows:(1)The overall scheme of the intelligent control system of the paddy field unmanned applicator is designed,including the autonomous navigation control system and the tele-operation system.The autonomous navigation system and the remote control system can not only operate as separate systems on agricultural machinery,but also can be used to make up Insufficient system,such as the loss of navigation signals,the remote operating system can ensure the safety of the operation.The driving control system included in the two systems is the key to the control of the whole machine of the applicator.The angle sensing information and the throttle pusher feedback information are used to control the direction and speed,and receiving and interpretting navigation information sent by the navigation module for linear path tracking control,receiving control commands sent by the remote operating system for vehicle travel control and providing secure operation guarantee.(2)Based on the overall design of the solution,the hardware selection and software design were carried out.EPC-9600I-L was used as the main control board.The CANopen data acquisition module and navigation module were connected via CAN bus,and the two RS485 serial ports were connected to the DTU module and spray system respectively.RS232 serial port is connected to the electric steering wheel.The data acquisition module collects the throttle push rod travel information,controls the throttle push rod action through the relay;receives the vehicle steering front wheel angle feedback information through the analog input and output module,outputs 0-5V analog voltage to control the vehicle travel action,and the video capture module uses the Ezviz C6 C camera to provide on-site image of the application machine.On this basis,the software design of the main process of driving control is carried out in the cross-compilation environment.The MQTT protocol is selected as the tele-operation communication protocol for the low-bandwidth unreliable network.Based on the Ezviz cloud SDK to the console software in the Java environment,the second development has realized the remote control operation and operation monitoring of the applicator without limit distance.(3)The segmentation pure tracking algorithm is designed for the linear path tracking control in most cases of autonomous navigation,including the outer arc path tracking algorithm and the inner arc path tracking control algorithm.The feasibility of the algorithm is verified by Matlab/Simulink simulation.Based on the IAE criterion,the key parameters of the preview distance in the pure tracking algorithm are optimized,and the optimal preview distance is finally determined to be 1.9 m.(4)The modified paddy field applicator was tested as a whole,including remote control performance test and linear path tracking test.The test results showed that the remote control stability was good,the data loss rate was low,and the average success rate could reach 96.7%.Straight line tracking control The medium control algorithm performs well on the hard ground and has strong robustness.However,the performance of the algorithm is reduced in the field test,but the operation requirements can still be achieved.