Development of electronic control system to automatically adjust spray output

Abstract

Agricultural pests and disease control is one of the main aspect of the crop production especially in orchards. Agricultural sprayers currently used in the orchards are basically constant rate air-assisted sprayers, which uses heavy stream of air to carry fine droplets toward the target. As, orchard trees vary in their size and geometry, spraying with these sprayers often results in either over spraying or under spraying. The variation in size and shape of the orchard trees makes necessary to take into consideration these tree parameters while spraying to adjust spray output to avoid losses due to over spraying. To adjust the amount of pesticide to be sprayed as per the tree size, an electronic control system was developed. The tree parameters were obtained using a high-speed ultrasonic sensor; a microcontroller was developed to control the system and to process the developed algorithm and variation in spray volume to be sprayed was achieved with a proportional solenoid valve. The developed system was tested in the laboratory to test the homogeneity of the flow rate sprayed through nozzle.