Abstract With the increase in population, humans have invented new methods such as greenhouse production to increase the quantity and quality of agricultural products. Compared to traditional farming, greenhouse cultivation is affected by a number of factors, including high planting density, high temperature and humidity, which creates conditions leads to the growth of pests and diseases. Agricultural pesticides are used to protect plants and crops from pests, diseases, and weeds, but they are also a major source of environmental pollution that negatively impacts the health of living organisms, including humans. In this study, a smart spraying robot with the ability to move along a cable was designed and developed to reduce human contact with pesticide, improve the quality of spraying, and reduce pesticide consumption. The intelligent robot is capable of accurately and autonomously spraying greenhouses without the need for human intervention. The robot moves along a cable installed above the crop rows and can spray plants from top to bottom and vice versa using a telescopic mechanism. The robot consists of a chassis, arms, drive and driven pulleys, a telescopic mechanism, a pesticide delivery system, a power transmission mechanism, electronic circuits, a cable, and a nozzle. Two modes of robot control were considered: intelligent and manual. In the intelligent mode, the user issues the spraying command by pressing the start button on a smartphone, and then the robot's movement and spraying are executed based on a program given to the robot. In the manual mode, the user controls the robot's movement and initiates spraying using a smartphone. The robot's performance was eva‎luated in the research greenhouses of rose plant at Isfahan University of Technology. The robot's performance was eva‎luated based on the effects of nozzle speed in the vertical direction (12, 15, and 18 meters per minute), pressure (1.4, 2.6, and 3.6 bar), leaf position (upper, middle, and lower), and nozzle type (flat fan nozzle and hollow cone nozzle) on the numerical median diameter, volumetric median diameter, coverage percentage, uniformity index of droplets spectrum, and droplet number per unit area using Miller paper based on a split-plot factorial design. The data were analyzed using SAS 9.4 software. The results showed that the flat fan nozzle produced droplets with smaller numerical median diameter and volumetric median diameter than the hollow cone nozzle. In addition, higher number of droplets per unit area was produced by the flat fan nozzle compared to the hollow cone one. Increasing the pressure from 1.4 to 2.6 and then to 3.6 bar decreased the numerical median diameter and volumetric median diameter by 15.4% and 9.9%, respectively, and increased the coverage percentage, droplet number per unit area, and the uniformity index of droplets spectrum. Increasing the nozzle speed from 12 to 15 and then to 18 meters per minute decreased the numerical median diameter, volumetric median diameter, and coverage percentage by 13.3%, 12.1%, and 25.7%, respectively, and increased the droplet number per square centimeter from 78 droplets at 12 meters per minute to 91 and 108 droplets at 15 and 18 meters per minute, respectively. The numerical median diameter was 7.3% higher on the lower leaf surface than on the middle and upper leaf surfaces. The volumetric median diameter was 2.4% and 13.6% higher on the lower leaf surface than on the middle and upper leaf surfaces, respectively. The coverage percentage was higher on the lower leaf surface than the others, and the uniformity index of droplets spectrum was lower on the lower leaf surface. The maximum and minimum pesticide consumption rates of the robot were 2.6 and 16.1 liters for spraying two rows of the greenhouse, respectively. Compared to motorized backpack and trolley sprayers, the robot used 55% and 82.9% less pesticide, respectively.

مهرنوش جعفري

امين اله معصومي

احمد ميره اي , نعمت اله اعتمادي شلمزاري