DEVELOPMENT OF A CROP ADAPTED SPRAY APPLICATION SYSTEM FOR SUSTAINABLE PLANT PROTECTION IN FRUIT GROWING
The objective of the project was to design and construct a model of sprayer that will ensure precise, efficient, and safe spray application in orchards according to actual needs and with respect to the environment. The Crop Adapted Spray Application (CASA) system will consist of three sub-systems: i) Crop Health Sensor CHS, ii) Crop Identification System CIS, and iii) Environmentally Dependent Application System EDAS. The Crop Health Status (CHS) is to be determined by a spectral sensor that analyses light reflected from apple leaves in the bandwidth 400-1600nm. With this sensor a plant stress due to apple scab (Venturia inaequalis) or powdery mildew (Podosphaera leucotricha) infection is identified in real time in order to determine the dose and timing of chemicals according to the crop health situation. For target identification (CIS), a new ultrasonic sensor has been developed that delivers real time data on target characteristics such as tree canopy width and density, based on the echo signal of ultrasound reflected from the fruit trees. A spray application system was also developed to apply variable, site-specific spray volume according to the tree width and density at different tree levels. In order to protect sensitive areas neighboring the orchards, the environmental circumstances will be identified (EDAS): wind velocity/direction by ultrasonic anemometer and orchard boundary, and sensitive areas such as surface water, melioration wells, sensitive crops, public areas, etc. by GIS/GPS. EDAS is being developed to adjust application parameters according to the wind situation and sprayer position in relation to sensitive areas. Nozzles can be altered to adjust droplet size; a novel fan construction allows the supporting airflow to the left and right hand sections of the nozzle to be adjusted independently, so that spray distribution is optimized and spray loss is minimized.
Doruchowski, G., Balsari, P. and Van de Zande, J. (2009). DEVELOPMENT OF A CROP ADAPTED SPRAY APPLICATION SYSTEM FOR SUSTAINABLE PLANT PROTECTION IN FRUIT GROWING. Acta Hortic. 824, 251-260
crop health status, target identification, GPS navigation, spectral analysis, ultrasonic sensor, dose adjustment, spray quality, air-jet adjustment