Design Of Target Pesticide Application Control System In The Orchard

With the development of science and technology, people pay more attention to foodsafety, the using of pesticides and agricultural security issues become more prominent.Spraying is an important part of agricultural production, implementation of the target variableis guaranteed to minimize pesticide facilities and reduce chemical contamination of importanttechnical measures. In this paper, advanced spraying machinery is expensive, mostly mediumand large self-propelled or towed spraying machinery, spraying machinery widespread andeffective use of domestic low pesticide, the use of high-capacity spray technology, lowautomation. With sensor technology, the wind sent spray technology, embedded Linuxdevelopment platform designed to target pesticide control system in the orchards. Thereal-time monitoring system through the spray pressure sensors, flow, speed and targetinformation, to achieve the target precision spraying.(1) Determine overall system design According to the general requirements of theproject design, the control system should be able to achieve the amount of spraying to controlvariables, with the target to achieve online control according to vehicle speed detectingchanges. Through a multi-program comparison analysis to determine the basis for changes inwalking speed and spraying machine can touch LCD set application rate per unit area, theultrasound probe target information via separate nozzles to achieve real-time adjustment ofopening and closing control the amount of pesticide spraying control program.(2) Buildding spraying volume control model Application rates are PID controlalgorithm experiments. The results show that: the valve opening time and proportionalrelationship, thereby regulating the flow can be established based on the PID controlalgorithm model; in the unit step signal input, the response time PID control systemapplication rates is0.25s.(3) Control system design According to system solutions, system implementation,monitoring and other hardware components are selected; order to Micro2440developmentboard as the core, the power module circuit, signal acquisition module circuit and solenoidvalves, electric control valve actuator module circuit are designed, and a controller is maked. (4) Control system software design Design and implementation of embedded controlsystems based on Linux. The data acquisition module and execution module drivers areprepared by C++language, which composed of ultrasonic sensor driver, traffic capture driver,speed collection of drivers for, electric control valve drivers and solenoid valve control driver;and the application rate control procedures, sprinklers status display program, the systemmain interface program, parameter setting interface program and digital soft keyboardinterface program and other program consisting of a interactive interface control program.(5) System debugging and verification test For each module of the study designhardware and software debugging, testing whether it can work as well as features designed tomeet the requirements; simultaneous detection systems to coordinate the work of variousmodules, system reliability and feasibility of the overall performance. The results showed that:the system can keep spraying parameters normally receive sensor data transmission, and canbe displayed in real time; system for speed, pressure and flow measurement accuracy are98.80%,97.39%, and96.23%; within the effective range of the system can be for targetdetection achieved independence nozzle opening and closing control; using PID controlalgorithm to control the application rate were monitored, the accuracy is94.60%，that thesystem application rate control precision to meet the design requirements, the system hasreached the level of application that can be used to control orchard spraying machine.