Design And Experiment Of Monitoring System For Orchard Sprayer Used In Hilly Mountain

The terrain of citrus orchards in China is mostly hilly and mountainous,and due to the geographical environment of hilly mountain orchards,it has the characteristics of large slope and difficulty for agricultural machinery to pass,resulting in great obstacles to the operation of agricultural machinery.The successful research and development of different types of agricultural rail transporter has enriched the forms of hilly mountain agricultural machinery operations,and provided an effective way to solve the obstacles faced by hilly mountain plant protection machinery operations.This paper designs an orchard spraying machine and wireless monitoring system with mountain rail transporter as the operation carrier,and the specific research content is as follows:1)Hardware design and implementation for orchard sprayer.According to the design requirements,the orchard sprayer test prototype model was determined,the shape size after adding the control box was 750mm×300mm×1000mm,and the circuit design and implementation of the orchard spraying machine control system including 51 microcomputer single-chip,remote control and receiver module,relay module,motor drive module,DC geared motor,PCF8591 voltage sampling module,LoRa wireless communication module,liquid crystal display module.2)Software design for orchard sprayer control system.According to the functional requirements of the spraying operation and the data transmission requirements,the control program is designed,the design procedure includes obtaining different functions corresponding to different key signals;using the micro-controller I/O port control relay to change the pump gear;designing the timer interrupt to generate PWM square wave algorithm to achieve the expansion and contraction and speed regulation of the sprayer reel;the acquisition of the working voltage through IIC communication;the linear interpolation algorithm to achieve the estimation of the remaining working power;and the use of serial port communication to send real-time data.3)Wireless communication design based on LoRa technology.The working mode of multiple LoRa modules are determined and its parameters are configured in combination with the AT command,and set its function mode to "broadcast and data monitoring" mode to realize long-distance wireless communication of data and extract SNR values and RSSI values.4)The design of the host computer based on Lab VIEW.The design of the login interface is completed,the display and visualization interface of voltage value data,residual working power,flow value data,and real-time spray pressure data is designed,the alarm processing function of data threshold limit and data abnormality is designed,and the function of one-click data storage in Excel table is designed to monitor the working status of the orchard sprayer.5)Functional test and overall system test.From the debugging and test results can be seen,after pressing the control box total switch,the control box LCD display shows the sprayer residual power percentage and "Turn on" string,respectively,after pressing the remote control pump function button and the reel function button,the orchard spraying machine can achieve the spraying operation function and the reel expansion and contraction and speed regulation function,the coil length is 30 m,the spraying range is3.6m ～ 7.8m,the spraying flow is 4.2L/min ～6.2L/min,the working time is 310 min,and the working voltage is 8.75V～ 12.65 V,the relationship curve between the average voltage value and the working time is fitted.From the remote control scheme test can know that the remote control b)is most in line with the actual work needs,the remote control range can reach 80 m,and the response time is 0.66 s ～ 0.72 s.Having completed the test of LoRa communication ranging,under the condition of sunny weather and general environmental complexity,the maximum communication distance of LoRa module is 600m～700m,and the RSSI value extracted within the effective communication distance ranges from-99.5d B～-10.40 d B;having completed the debugging of the host computer interface,which can be seen from the debugging results,and the host computer can display the sprayer operating parameters in real time,and the parameters are visualized and stored in the chart.