RHEA project achievement: an innovative spray concept for pesticide application to tree crops equipping a fleet of autonomous robots. Report 1356

The new Community rules on the reduction of risks to the environment and food safety require a breakthrough innovation in all sectors especially in agriculture where there is a strong pressure due to the remarkable use of pesticides and herbicides. In this context, it’s a necessary reinterpretation of the classic management methods to a new modern agricultural concept the "integrated agronomic approach" for a targeted individual care and aware of the plant, of the biotic and environmental components that interacting. The operating units of "agricultural mechanics and mechanization" of Pisa and Florence have the task of establishing the actuators in the final three specific contexts: wheat, corn and olives. In the first case, the robot will perform chemical weed control, while in the corn case will be used only mechanical and thermal physical tools. For the third scenario we worked on the design and testing of an automatic unit for the application of pesticides sprayed on crops, especially olive trees and woody crops for biomass energy production. The objective of the Unit of Florence is the realization of the sprayer for canopy based on the geometry of the intensive and super-intensive olive plant. A complex air assisted sprayer has been designed and realized as concentration of the latest innovation of the international research integrated in the RHEA robot system. The semi-mounted sprayer applied to small autonomous tractor equipped with many typologies of sensor is able to recognize the presence, shape and thickness of the various horizontal bands of the canopy by adjusting the activation, the amount, the type of spraying. Moreover, is possible, separately on each band, to control the direction of air diffusors and the airblast flow rate in relation to the presence or thickness of the canopy. An innovative device system to control dose application proportionally to the canopy band thickness has been applied by an high frequency solenoid valve driven by variable duty cycle controller. New RHEA spray concept, has the aims to follow the rules imposed by the European Union to reduce pollution caused by then distribution of pesticides.