A Novel Modular, Extendable Mobile Robot for Image Data Collection Task in a Greenhouse

Abstract

Early detection of diseases based on the appearance of the crop can reduce crop losses. However, early detection of diseases by human visual inspection or manual image taking is costly and ineffective in time and labor. This paper presents a novel robot working in greenhouses that automatically collects image data of crops. The image data obtained by the robot can be used not only for the early detection of diseases but also for various other applications, such as monitoring growth conditions. The proposed robot is modular, consisting of a mobile chassis module and nestable modules. The smaller nestable module can be nested in the larger nestable module and lifted and lowered along rails mounted in the larger nestable module. Each nestable module’s sides are equipped with stepper motors, threaded rods, rails, and cameras. The stepper motor’s rotation allows the camera to move up and down. Therefore, the user can decide how many nestable modules to use to collect image data depending on the height of the crops. We use three nestable modules as needed in this work, and the robot can extend to approximately 3 m for collecting essential image data. The nestable module is mounted on the mobile chassis module. The mobile chassis module is also modular. It consists of four drive modules and a base frame module. The drive module consists of a DC gear motor and a servo motor, which can be steered separately, meaning that the robot’s form of movement can be configured as required.