STUDY OF THE EFFICIENCY OF UAV APPLICATION FOR ULTRA-SMALL VOLUME SPRAYING OF CROPS
Authors: Khalin S. ,   L. Pogorilyy UkrNDIPVT, Voinovskyi V. , Haidai T. ,   Leonid Pogorilyy UkrNDIPVT
Published: July 2024

The purpose of the work is to study the effectiveness of using UAVs for ultra-small-volume spraying of crops by assessing the degree of coverage of the target plant surface with drops. Methods and materials: The study of the effectiveness of the use of UAVs in agriculture for high-quality spraying of crops was carried out on the lands of UkrNDIPVT named after L. Pohorily, using mobile sprayers «JT 6L-606» and «JT 15L-608P». Research of the «JT 6L-606» mobile sprayer model was carried out with a colored aqueous solution. The evaluation indicators were the median mass diameter of the settled droplets and the density of the coating of the treated surface with drops of the working solution, which were evaluated in accordance with the standard methodology of SOU 74.3-37-266:2005 “Testing of agricultural machinery. Tractor and self-propelled sprayers. Program and test methods”. Results. The size of the drops is a determining qualitative indicator of spraying. It characterizes the degree of grinding of the liquid and significantly affects the effectiveness of action and the rate of consumption of plant protection products. The value of the median mass droplet diameter, obtained as a result of tests of the «JT 6L-606» mobile sprayer, showed that the relative number of droplets whose diameter is less than or equal to 100 μm is 50% of the total number of droplets. However, asymmetry of droplet deposition on the right and left sides of the UAV and high unevenness of the distribution of drops of the working fluid along the width of the grip were found.Therefore, this sprayer model required additional settings in the future. Under the established conditions and modes of testing of the «JT 15L-608P» mobile sprayer, the obtained value of the median mass droplet diameter proved that the relative number of drops whose diameter is less than or equal to 100 μm is 60% of the total number of drops. The degree of coverage with drops of the target surface on the right and left sides of the UAV (grip width) of the «JT 15L-608P» sprayer was relatively symmetrical. Conclusions. According to the results of experimental studies of the effectiveness of the use of unmanned aerial sprayers «JT 6L-606» and «JT 15L-608P», it was established that in both unmanned mobile sprayers, the obtained values of the median mass diameter of drops, which are characteristic of the process of mechanical spraying, meet the requirements of ultra-small-volume spraying. However, the uneven distribution of drops of the working fluid along the width of the UAV was noted, which requires additional settings. When setting up agricultural drones, it is recommended to pay attention to the degree and impact of drift, which can be significantly reduced by following the following recommendations: reduce the distance between the rod and the target (the height of the rod should be approximately the same as the distance between the nozzles); use the coarsest effective droplet size typically achieved with drift-reducing nozzles such as air induction. Keywords: unmanned aerial vehicles, distribution uniformity, aerial spraying, quality of surface coverage, droplet size.