Design And Experimental Study Of Trichogramma Pill Delivery System For Complex Wind Field

Biological control is the use of biological control means to deal with another biological method,the use of biological control means to control pests and diseases does not cause pollution to the environment while not affecting human health and has a broad future,and the use of Trichogramma for pest control is one of the commonly used biological control methods in the field of biological control.At present,Trichogramma’s delivery methods mainly include artificial delivery,mechanical delivery and drone delivery.Rely on manual delivery,labor efficiency is low,high cost.The use of mechanical delivery,fuel consumption is large,will cause pollution to the environment,and due to changes in the external environment,the purpose of accurate delivery cannot be achieved.In recent years,with the application of plant protection UAV in agriculture becoming more and more extensive,the use of UAV to deliver Trichogramma provides a new solution for the application of biological control.Drone delivery of Trichogramma has advantages such as convenient operation and strong adaptability to the environment.However,currently,the technology of drone delivery of Trichogramma is not mature,and there are some problems such as device blockage,low efficiency and poor accuracy.Therefore,a Trichogramma pill delivery system under complex wind field was designed and tested in this paper.In view of the fact that Trichogramma pills are easily affected by wind speed,air resistance and other factors in the process of delivery,this paper proposes an adaptive control method to control the motion trajectory of Trichogramma pill.The high-speed rotating friction wheel is used to deliver Trichogramma pill,so as to achieve accurate and rapid delivery of Trichogramma pill.In addition,a series of relevant studies are conducted on the performance of the delivery system.The feasibility and practicability of the delivery system are verified through the test and experiment,the specific research contents are as follows:(1)Firstly,the complex wind field is defined,and the influence of complex wind field on the motion of Trichogramma pill is explored by studying the trajectory of Trichogramma pill under ordinary wind field and simulating the wind field of UAV rotor.By using the method of theoretical analysis,the motion trajectory model of Trichogramma pill under ordinary wind field is established.The motion trajectory of Trichogramma pill is solved and calculated by MATLAB software,and the law affecting the motion of Trichogramma pill is obtained.The finite element simulation method is used to obtain the rotor wind field of the UAV,and the distribution law of the rotor wind field of the UAV is obtained,which lays a theoretical foundation for the design of the delivery system.(2)Based on the analysis of the influence of complex wind field on the movement of Trichogramma pill,a Trichogramma delivery system for complex wind field was designed.The key components of the delivery system are analyzed and designed by theoretical analysis,combined with the trajectory prediction model,the adaptive controller is studied to control the rotation of the motor in real time to control the trajectory of the Trichogramma pill and achieve the purpose of accurate delivery.(3)In response to the problems of long detection time and poor accuracy in extracting flight navigation lines from multi-rotor plant protection UAVs,a visual navigation method is proposed to extract the navigation line of multi-rotor UAV.Firstly,the binary image is obtained using an improved super-greening feature algorithm and the maximum inter-class variance method,while morphological processing is combined to improve the image quality,and the dynamic region of interest is determined by constraining the pixel threshold,the crop edge contour was extracted by adaptive edge detection algorithm,finally,the UAV flight navigation line was fitted by Theil-Sen estimation method.(4)The feasibility and practicability of Trichogramma pill delivery system were verified by experiments,a six-rotor plant protection UAV was selected as the flight platform,equipped with Trichogramma launcher.The Box-Behnken test design was carried out with launch height,launch speed and launch interval as test factors,and the accuracy of Trichogramma pill landing point as test index.Design-Expert software was used to conduct variance analysis on the data,and response surface analysis was used to explore the influence of various experimental factors on the accuracy of Trichogramma pill.The regression model between test factors and test indicators was established,and the parameters were optimized by response surface analysis method,and the optimal combination parameters were obtained,finally,the feasibility and practicability of Trichogramma delivery system were verified by field test.