Study on the Mechanism of Droplet Precision Delivery and Target Matching in Tropical Fruit Trees by Unmanned Aerial Spraying Systems

• Grant number: 25/16508-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2025
• End date: January 31, 2028
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Marcelo da Costa Ferreira
• Grantee: Thales Gomes dos Santos
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated research grant: 24/15469-9 - Study on the Mechanism of Droplet Precision Delivery and Target Matching in Tropical Fruit Trees by Unmanned Aerial Spraying Systems, AP.PFPMCG.R

Abstract

The use of drones in agriculture, with multiple rotors and movable wings, began in a commercial stage around 2010, with official regulation in Brazil occurring in 2017. Since its introduction, the demand for its use has been growing, with natural concerns about its efficiency and safety. In the case of drones for the application of phytosanitary products, efficiency considers the expected effects and safety. In this context, there are marked differences in the use of drones, which are related to their load capacity, agility, height and speed of application, the dynamics of droplet distribution based on the air flow provided by the propellers, the absence (so far) of agitation of the mixture inside the tank and the reduced volume of application practiced. These characteristics have generated some insecurity in the adoption of the technique due to the uncertainty that the expected result will be achieved. This is also due to the little research carried out with the technique, which is recent, especially compared to other application techniques and even due to its widespread use, without considering the main positioning capabilities of the technique. In traditional applications, there are situations in which efficiency and safety can result in damage due to drift and runoff. The possibility of performing localized applications with drones, complementing other techniques, can represent a good justification for adoption. In this context, the objective of this research is to evaluate general aspects of the application of phytosanitary products with drones, in fruit trees and in coffee and lychee, through the evaluation of highly concentrated sprays used for application with very low spray volumes (pH, electrical conductivity, viscosity, surface tension), in addition to direct evaluations on the crops of canephora and arabica coffee (Espírito Santo and São Paulo) and lychee (São Paulo). The work will have a stage carried out by partners in China, in which machine learning evaluations will be carried out, aiming to perform more accurate and precise applications on the plants, aiming to increase the proportion of the spray that reaches the target and avoiding losses due to drift. This is expected to expand knowledge about remotely piloted aircraft, which are promising for phytosanitary treatment carried out efficiently and safely. (AU)