Optimization Of Spray Parameters Of Plant Protection UAV And Control Efficiency On Diaphorina Citri

The performance of spray nozzle atomization,the physicochemical properties of liquid medicine and the parameters setting have greatly effect on the control efficiency of plant protection UAV.In this paper,based on ZHKU-0404-02 plant protection UAV,the effects of operating altitude and flying speed on the control efficiency of Diaphorina citri were analyzed after sprinklers and dosage forms selection.The specific research contents and results are as follows:?1?The effects of different fan-shaped sprinklers and hollow cone sprinklers on atomization performance were analyzed under different cross-wind velocities and spraying pressures.Compared with the hollow cone sprinklers,the fan-shaped sprinkler achieves better performance in drift resistance when the cross wind speed decreases below 3 m/s.therefore the fan-shaped sprinkler is suitable for insecticide spraying of plant protection UAV.?2?Six formulations of imidacloprid?20%imidacloprid solution,10%imidacloprid wettable powder,5%imidacloprid emulsifiable oil,30%imidacloprid microemulsion,35%imidacloprid suspension and 70%imidacloprid water dispersible granules?were studied on the volatility,viscosity,tension and the median size.30%imidacloprid microemulsion provided superiority as compared with other formulations.With the low volatilization,easy wet stretching and easy atomization,30%imidacloprid microemulsion was selected for UAV spraying.?3?The effects of different operating altitudes?0.6 m,1.2 m and 1.8 m?and flight velocities?1 m/s,2 m/s and 3 m/s?of plant protection UAV on droplet deposition were studied with the optimized fan-shaped nozzle and 30%imidacloprid microemulsion.The results showed that the largest median droplet and deposition density were obtained in the upper layer of Citrus canopy;the droplet deposition effect was remarkable when the flight speed is less than 2 m/s;based on the operational height 1.2 m and the flight speed 1 m/s,the droplet deposition density was the largest no matter in the upper,middle and lower layers of Citrus canopy,with the values of 32.40 NO.cm^-2,26.01 NO.cm^-2 and 22.38 NO.cm^-2,respectively.?4?Comparation of control effect on Diaphorina citri between artificial backpack mode and plant protection UAV with the1.2 m operating altitude and the 1 m/s flight speed were done.The results showed that the control effect of plant protection UAV on Diaphorina citri?81%?was lower than that of artificial backpack operation?91%?,but the operation efficiency was about 30 times higher.