Design And Implementation Of Spray Boom Position Measurement And Control System For Plant Protection Machinery

With the continuous development of modern agriculture,the demands for large-scale plant protection machinery have increased year by year,and the intelligentized development of large-scale plant protection machinery has become a key factor in achieving “precise agriculture”.There is a big research gap on the intelligentization of large-scale plant protection machinery between China and the developed countries in the west.As the most important component of plant protection machinery operations,the performance of the spray boom affects the operation efficiency and spraying effect.In this thesis a large-scale plant protection machine boom control technology and intelligent monitoring system are analyzed.It is found that the control of position of the boom position control system designed in China is insufficient and the system function is single.Thus,it is necessary to design a intelligent system for plant protection machinery that integrates multi-target of monitoring and control.To meet the demand of the system,the position of the boom,the remaining amount of the liquid,the nozzle state and the spray pressure are selected as the main monitoring objects.Then the hardware selection and the selection of the software development platform are completed according to the overall design of the system.In hardware design,ARM-A8 is used as the core controller,and the peripheral auxiliary circuit,CAN bus communication circuit and LCD display circuit are designed.In terms of software design,Linux is chosen as the operating system and QT as the main software development environment.And then the system’s display function,setting function,alarm function,CAN bus communication function are developed.According to the characteristics of the hydraulic servo system of the boom actuator,an intelligent control algorithm switching between fuzzy and PID is designed and programmed based on C++programming language to make the position of the boom is controlled in real time.After completing design and developed the system,let a PC simulate the front-end data sensors and spray boom system,and CAN bus is used to communicate between the PC and the OK335xS-II based on ARM-A8 test the developed system.Main functions of the system are tested and the results show that the system can run stably,the alert and setting function are normal,and the designed boom position controller effectively can control the boom position tothe desired setting point.