Spraying analysis for a coconut climbing robot

Due to the recent epidemic outbreak of the coconut black-headed caterpillars in the southern provinces of Thailand, this research aims to develop a tree-specific pest control equipment using robotic and computer simulation technology. The climbing device allows the spraying head to reach the foliage of the coconut regardless of the height of the tree. The spraying should access the area of the foliage that is infested with the coconut black-headed caterpillars. This research proposes the new technique of modeling spray deposition on to the coconut leaves using image processing and a probabilistic model. By spraying the substance directly to the foliage from an optimum position, the proposed method shows that it can largely reduce the amount of chemical pesticide. The coconut climbing robot was developed as a wheel robot with a series elastic actuator. There are two motors on the robot, the drive motor drives the robot up and down the tree while the other motor is attached to a spring mechanism which keeps the holding force between robot and the tree. The robot can climb up and down the coconut tree at an average speed of 0.3 m/s and can carry a sprayer with an additional payload of 2 kg.