Recently,the growing use of unmanned aerial vehicles(UAV)for pesticide application has been reported against a wide range of crops with promising results in East Asian countries such as Japan,South Korea and China.Thi...Recently,the growing use of unmanned aerial vehicles(UAV)for pesticide application has been reported against a wide range of crops with promising results in East Asian countries such as Japan,South Korea and China.This UAV-based application technology for agrochemicals is considered as a high efficiency alternative to the conventional manual spray operations and a low-cost choice as compared to the classical manned aerial application.However,the technology adoption rate and the designed optimal sprayer suitable for drone application for small scale farm remains at the development stage in China and also in Japan.This paper reports the current status of drone pesticide application in China and makes comparisons with its neighbor countries Japan and South Korea in terms of different UAV platforms and their implementation in plant protection for different crops.Challenges and opportunities for future development of UAV-based pesticide application technology are also discussed.展开更多
In order to explore the spatial pesticide spraying deposition distribution,the downwash flow field characteristics for unmanned aerial vehicle(UAV)pesticide application with accurate flight height and velocity and the...In order to explore the spatial pesticide spraying deposition distribution,the downwash flow field characteristics for unmanned aerial vehicle(UAV)pesticide application with accurate flight height and velocity and the relationship of these two aspects,a novel measurement method was proposed in this paper.A model‘3WQF80-10’single-rotor diesel UAV was tested using this method in wheat field and the effects of flight direction,flight parameters and crosswind on the distribution of spatial spraying deposition quality balance(SSDQB)and the downwash flow field distribution were researched.A cuboid aluminum sampling frame of spatial spraying deposition quality balance(SFSSDQB)with monofilament wires was made for collecting the droplets in four directions,and a set of multi-channel micro-meteorology measurement system(MMMS)was applied for measuring the downwash wind speed in three directions.Besides,BeiDou Navigation Satellite System(BNSS)was used for controlling and recording the working height,velocity and track of this model of single-rotor UAV.The results showed the distribution of the spatial spray deposition and the downwash flow field of UAV could be measured effectively at exact flight height and velocity via this method.When the average wind speed was 0.9 m/s,the average temperature was 31.5℃ and the average relative humidity was 34.1%,and the average distribution ratios of spraying deposition for model‘3WQF80-10’UAV on the upwind part,the top part,the downwind part and the bottom part were 4.4%,2.3%,50.4%and 43.7%,respectively.The flight directions of forward and backward had an impact on droplet deposition distribution and the working effect of flying backwards,with 60%of deposition ratio of the bottom part of the SFSSDQB,was better than flying forward.There was a linear negative correlation between the coefficient of variation(CV)of the bottom part and the flight height and the coefficient of determination was 0.9178,which means that the deposition distribution becomes more uniform with the increase of height.Additionally,there was a linear positive correlation between weighted mean deposition rate and crosswind speed and the coefficient of determination was 0.9684,which shows the deposition distribution gets more concentrated towards the downwind part with the rise of crosswind speed.Therefore,according to the results of tests of downwash airflow speed,it is shown that regardless of the flight direction and height and the crosswind,all these factors influence the droplet deposition distribution via weakening the intensity of the downwash airflow field in the direction perpendicular to the ground.The results can provide valuable information for the research of UAV pesticide application techniques and the establishment of the standard of spraying deposition and drift tests of UAV in crop field.展开更多
Since the 2010s,unmanned aerial vehicle(UAV)sprayer was applied more and more widely for low-volume aerial pesticides spraying operations in China.However,droplets from the UAV sprayer have a higher drift risk due to ...Since the 2010s,unmanned aerial vehicle(UAV)sprayer was applied more and more widely for low-volume aerial pesticides spraying operations in China.However,droplets from the UAV sprayer have a higher drift risk due to more fine droplets sprayed and a higher flight height than ground sprayers.Study on UAV spray drift has been a new hot spot within the field of pesticide application technology.Most of previous studies used direct field methods for spray drift,but the meteorological conditions in field were unstable and uncontrollable,and drift research under an actual operation state in wind tunnel has not been reported.Therefore,25 treatments of wind tunnel measurements and droplets spectrum tests of 10 models of nozzles were conducted to explore the influence factor on spray drift characteristics of UAV chemicals application in this study.A spray unit with a rotor of UAV was innovatively installed in wind tunnel,and the airstream from the wind tunnel was regarded as the relative moving natural wind to simulate the flight status.The airborne and the sediment spray drift was measured to study the effects of the nozzle type and size(flat fan,hollow cone and air-inclusion nozzles),flight speed,adjuvant(DRS-60,Y-20079,MF and G-611)and meteorological parameters(20°C&40%,20°C&80%,30°C&40%and 30°C&60%).The drift potential(DP)and the drift potential reduction percentage(DPRP)in vertical and horizontal directions were obtained for each test.Both nozzle type and size had an impact on the spray drift potential obviously by affecting the droplet size and the ratio of fine droplets,and the regression linear models between DPRPV/DPRPH and DV50,V75 were established(R2=0.934/0.925).Flight speed also had a significant effect on the spray drift characteristics,and reducing the flight speed could increase the DP effectively.Adding spray adjuvants could affect the DP under experimental meteorological parameters,and the anti-drift performance ranked in the order of DRS-60>MF>Y-20079>G-611.Recommendations were proposed in order to reduce the spray drift for UAV sprayer’s operation.These findings can contribute to provide guidelines and technical support for the wind tunnel spray drift tests of UAV and the field operation regulation of unmanned aerial PPP application.展开更多
Pesticide droplet is evaporating during the falling from the nozzle to the target.This dynamic evaporation is influenced by ambient temperature,relative humidity(RH),adjuvant type and concentration.In the evaporation ...Pesticide droplet is evaporating during the falling from the nozzle to the target.This dynamic evaporation is influenced by ambient temperature,relative humidity(RH),adjuvant type and concentration.In the evaporation process,the droplet size at different height is affected by the droplet evaporation.Based on this,this study determined the droplet dynamic evaporation by collecting the droplets from different height via silicone oil method with a certain temperature and RH.Eight adjuvants were chosen,including three organo-silicon,three vegetable oil and two non-ionic,with five concentrations.All droplets were generated by a droplet generator.The results showed that the type of adjuvant,ambient temperature and RH had no significant influence on droplet size generated by droplet generator.All the adjuvants in this experiment cannot reduce dynamic evaporation;Concentration of adjuvant made a difference in dynamic evaporation.This could be because of the property of adjuvant.Organo-silicon adjuvants have a negative correlation with water vapor pressure,it showed less dynamic evaporation at high temperature and RH.Vegetable oil and non-ionic adjuvant,they are the same as the controlled blank that the dynamic evaporation reduces with decreasing temperature and increasing RH.展开更多
基金the grants of Special Fund for Agro-scientific Research in the Public Interest from the Ministry of Agriculture,China(201203025,201503130)International Co-operation Project“UAV chemical application technique for rice”from the Chinese Ministry of Agriculture and National Natural Science Foundation of China(31470099)+1 种基金China International Science and Technology Cooperation Project(2010DFA34570)“New Technique for Chemical Application”by Chinese State Administration of Foreign Experts Affairs(SGCAST01601710).
文摘Recently,the growing use of unmanned aerial vehicles(UAV)for pesticide application has been reported against a wide range of crops with promising results in East Asian countries such as Japan,South Korea and China.This UAV-based application technology for agrochemicals is considered as a high efficiency alternative to the conventional manual spray operations and a low-cost choice as compared to the classical manned aerial application.However,the technology adoption rate and the designed optimal sprayer suitable for drone application for small scale farm remains at the development stage in China and also in Japan.This paper reports the current status of drone pesticide application in China and makes comparisons with its neighbor countries Japan and South Korea in terms of different UAV platforms and their implementation in plant protection for different crops.Challenges and opportunities for future development of UAV-based pesticide application technology are also discussed.
基金supported by Special Fund for Agro-scientific Research in the Public Interest(201503130)National Science Fund Projects(31470099).
文摘In order to explore the spatial pesticide spraying deposition distribution,the downwash flow field characteristics for unmanned aerial vehicle(UAV)pesticide application with accurate flight height and velocity and the relationship of these two aspects,a novel measurement method was proposed in this paper.A model‘3WQF80-10’single-rotor diesel UAV was tested using this method in wheat field and the effects of flight direction,flight parameters and crosswind on the distribution of spatial spraying deposition quality balance(SSDQB)and the downwash flow field distribution were researched.A cuboid aluminum sampling frame of spatial spraying deposition quality balance(SFSSDQB)with monofilament wires was made for collecting the droplets in four directions,and a set of multi-channel micro-meteorology measurement system(MMMS)was applied for measuring the downwash wind speed in three directions.Besides,BeiDou Navigation Satellite System(BNSS)was used for controlling and recording the working height,velocity and track of this model of single-rotor UAV.The results showed the distribution of the spatial spray deposition and the downwash flow field of UAV could be measured effectively at exact flight height and velocity via this method.When the average wind speed was 0.9 m/s,the average temperature was 31.5℃ and the average relative humidity was 34.1%,and the average distribution ratios of spraying deposition for model‘3WQF80-10’UAV on the upwind part,the top part,the downwind part and the bottom part were 4.4%,2.3%,50.4%and 43.7%,respectively.The flight directions of forward and backward had an impact on droplet deposition distribution and the working effect of flying backwards,with 60%of deposition ratio of the bottom part of the SFSSDQB,was better than flying forward.There was a linear negative correlation between the coefficient of variation(CV)of the bottom part and the flight height and the coefficient of determination was 0.9178,which means that the deposition distribution becomes more uniform with the increase of height.Additionally,there was a linear positive correlation between weighted mean deposition rate and crosswind speed and the coefficient of determination was 0.9684,which shows the deposition distribution gets more concentrated towards the downwind part with the rise of crosswind speed.Therefore,according to the results of tests of downwash airflow speed,it is shown that regardless of the flight direction and height and the crosswind,all these factors influence the droplet deposition distribution via weakening the intensity of the downwash airflow field in the direction perpendicular to the ground.The results can provide valuable information for the research of UAV pesticide application techniques and the establishment of the standard of spraying deposition and drift tests of UAV in crop field.
基金This study was supported by Sino-German Cooperation Project(31761133019)supported by National Natural Science Foundation of China,National Key R&D Program of China(2017YFD0200304)+1 种基金and China Postdoctoral Science Foundation Funded Project(2019M650907)The authors would like to thank Mr.Sven Nolten and other staff of Institute for Application Techniques in Plant Protection,JKI and all staff of CCAT,China Agricultural University for their contributions to this work.
文摘Since the 2010s,unmanned aerial vehicle(UAV)sprayer was applied more and more widely for low-volume aerial pesticides spraying operations in China.However,droplets from the UAV sprayer have a higher drift risk due to more fine droplets sprayed and a higher flight height than ground sprayers.Study on UAV spray drift has been a new hot spot within the field of pesticide application technology.Most of previous studies used direct field methods for spray drift,but the meteorological conditions in field were unstable and uncontrollable,and drift research under an actual operation state in wind tunnel has not been reported.Therefore,25 treatments of wind tunnel measurements and droplets spectrum tests of 10 models of nozzles were conducted to explore the influence factor on spray drift characteristics of UAV chemicals application in this study.A spray unit with a rotor of UAV was innovatively installed in wind tunnel,and the airstream from the wind tunnel was regarded as the relative moving natural wind to simulate the flight status.The airborne and the sediment spray drift was measured to study the effects of the nozzle type and size(flat fan,hollow cone and air-inclusion nozzles),flight speed,adjuvant(DRS-60,Y-20079,MF and G-611)and meteorological parameters(20°C&40%,20°C&80%,30°C&40%and 30°C&60%).The drift potential(DP)and the drift potential reduction percentage(DPRP)in vertical and horizontal directions were obtained for each test.Both nozzle type and size had an impact on the spray drift potential obviously by affecting the droplet size and the ratio of fine droplets,and the regression linear models between DPRPV/DPRPH and DV50,V75 were established(R2=0.934/0.925).Flight speed also had a significant effect on the spray drift characteristics,and reducing the flight speed could increase the DP effectively.Adding spray adjuvants could affect the DP under experimental meteorological parameters,and the anti-drift performance ranked in the order of DRS-60>MF>Y-20079>G-611.Recommendations were proposed in order to reduce the spray drift for UAV sprayer’s operation.These findings can contribute to provide guidelines and technical support for the wind tunnel spray drift tests of UAV and the field operation regulation of unmanned aerial PPP application.
基金This work could be carried out due to the financial supported from the National Natural Science Foundation of China(No.31761133019)National Key Research and Development Plan of China(No.2017YFD0700903,2017YFD0200300)National Modern Agricultural Industrial Technology System of China(No.CARS-28-20).
文摘Pesticide droplet is evaporating during the falling from the nozzle to the target.This dynamic evaporation is influenced by ambient temperature,relative humidity(RH),adjuvant type and concentration.In the evaporation process,the droplet size at different height is affected by the droplet evaporation.Based on this,this study determined the droplet dynamic evaporation by collecting the droplets from different height via silicone oil method with a certain temperature and RH.Eight adjuvants were chosen,including three organo-silicon,three vegetable oil and two non-ionic,with five concentrations.All droplets were generated by a droplet generator.The results showed that the type of adjuvant,ambient temperature and RH had no significant influence on droplet size generated by droplet generator.All the adjuvants in this experiment cannot reduce dynamic evaporation;Concentration of adjuvant made a difference in dynamic evaporation.This could be because of the property of adjuvant.Organo-silicon adjuvants have a negative correlation with water vapor pressure,it showed less dynamic evaporation at high temperature and RH.Vegetable oil and non-ionic adjuvant,they are the same as the controlled blank that the dynamic evaporation reduces with decreasing temperature and increasing RH.
