Research And Implementation Of Anti-drift Spraying Control Technology For Orchards

In view of the serious problem of pesticide waste caused by wind-driven spray droplet drift in orchards,we conducted research on anti-drift spray control technology in orchards,monitored the environmental information of orchards and the operation status of implements through IOT sensing technology,built anti-drift spray control strategy,developed anti-drift spray control system,and realized intelligent control of wind curtain wind speed of sprayers according to the relative wind speed between rows and vehicle speed,which suppressed droplet drift,improved pesticide The research was carried out as follows.The specific research contents are as follows:(1)Research on the prediction model of fog droplet driftFog droplet drift prediction model is a prerequisite for intelligent control of wind curtain wind speed.Based on the team’s orchard wind-driven anti-drift sprayer,indoor experiments were conducted to study the relationship between the droplet drift rate and different side wind speeds and wind curtain wind speeds,and the droplet drift prediction model was constructed using nonlinear surface fitting.The test results showed that the optimal wind curtain wind speed determined by the prediction model could effectively suppress the droplet drift caused by interrow wind,and avoid the rebound of droplet drift rate caused by high wind curtain wind speed,which improved the spraying performance by 9.07%.This droplet drift prediction model is practical for achieving efficient drift control and improving application efficiency,and can provide a theoretical basis for drift control in orchards.(2)Study of anti-drift control model for fog dropletsAiming at the problems of weak parameter adjustment ability and poor control effect of traditional PID control system,a method of optimizing PID parameters by using TSSA is proposed to build a fog drop anti-drift control model based on TSSA-PID.Firstly,the controller is designed according to the performance requirements such as real-time anti-drift control,PID is determined as the control framework and SSA is the parameter optimization method;secondly,Tent chaos mapping,random following strategy and dimension-by-dimensional lens imaging reverse learning are introduced in SSA to obtain TSSA,which improves and balances its global search capability and local optimization seeking capability;after that,the system transfer function and the fitness function are constructed.The TSSA-PID fog-drop anti-drift control model is constructed by using TSSA to find the optimization of PID parameters;finally,the Tra-PID,TSSA-PID,SSA-PID,SGA-PID and GWO-PID controllers are simulated and analyzed in MATLAB/Simulink environment.The test results show that the use of TSSA-PID control model improves the response speed,reduces the response time by 45.77% and the overshoot by 13.21% on the basis of maintaining less overshoot,which can ensure the accuracy and efficiency of air curtain wind speed regulation and has good practicality.(3)Implementation and field verification of anti-drift spray control system for orchardsIn order to realize the automatic control of wind curtain and wind speed when applying medicine in orchards,and to monitor the environmental information and equipment status in orchards when applying medicine,we developed an intelligent measurement and control system based on STM32F4 for anti-drift spraying in orchards.Firstly,the overall design of the system software and hardware is determined by the requirement analysis,then the selection of the detection modules such as wind speed,vehicle speed,temperature and humidity,feedback,etc.and the control modules such as LCD display and butterfly valve is completed,and finally the program is written to realize the function of each module and complete the system construction to realize the real-time monitoring of environmental information and equipment status and intelligent anti-drift control in the process of orchard application.The orchard validation test results show that the orchard anti-drift spraying intelligent measurement and control system reduces 13% of air droplet drift,reduces 16.13% of ground droplet loss,improves 11.97% of canopy droplet coverage,suppresses the effect of side wind speed on spraying drift,and makes canopy droplet deposition more uniform.In conclusion,this thesis researched the fog droplet drift prediction model and fog droplet drift control model for the demand of fog droplet drift prevention in orchard application process,and designed and implemented an intelligent measurement and control system for orchard drift prevention spray based on the above model.The experiment shows that this research can effectively reduce the mist droplet drift,which can provide a new idea for the anti-drift application in orchards and promote the rapid development of anti-drift application technology.