Development of Robot System for Tomato Production in Mobile Cultivation Facility

本研究的目的是在移动栽培设施中实现番茄生产工作的自动化。番茄生产需要做很多工作。在这些工作中，我们讨论了果实收获，茎训练和落叶。在移动式栽培设备中，番茄植株随着栽培床的移动而移动。为了在设施中应用，我们对固定式机器人进行了研究。为实验制造的机器人主要由机械手、三维视觉传感器、末端执行器和个人计算机组成。三维视觉传感器扫描由波长为一条直线的红光和红外线组成的激光束。它向计算机输入了三幅图像；一个距离图像，一个红外图像和一个红色图像。每张图像的像素数为50000。通过处理这些图像，可以识别出果实、茎、叶和茎支撑杆的位置。进行了采收、茎干训练和落叶的基础试验。樱桃番茄果实需要连同花萼一起收获。为了与花萼一起收割，收割末端执行器配备了一个半圆形的部分来拉动花梗。通过牵拉运动，在节理位置切断花梗，大部分果实随花萼一起收获。通过用一个弹性环将主杆绑在杆上来完成杆的训练。圆环被分割成c形。环是通过末端执行器的伸展运动打开的。然后，它被移动到主杆和杆的位置，使它们被环包围。通过阻止膨胀，环通过它的弹性夹住了杆和杆。还进行了落叶试验。叶柄被末端执行器抓住，并被末端执行器的扭转运动折断。

The purpose of this study is to automate tomato producing works in a mobile cultivation facility. Various works are required for the tomato production. Among these works, we discussed fruit harvesting, stem training and defoliation. In the mobile cultivation facility, tomato plants move with the movement of the cultivating beds. For the application to the facility, we studied on stationary robot.The robot manufactured for the experiment consisted mainly of a manipulator, a 3-D vision sensor, an end-effector and a personal computer. The 3-D vision sensor scanned a laser beam consisting of red and infrared components of wavelength in a line. It fed three images to the computer ; a range image, an infrared image and a red image. Number of pixels of each image was 50000. Locations of fruits, stems, leaves and a stem-supporting pole were recognized by processing these images. Fundamental experiments of harvesting, stem training and defoliation were carried out. Cherry tomato fruit needs to be harvested with its calyx. To harvest it with the calyx, the harvesting end-effector was equipped with a semicircular part that pulled the peduncle. By the pulling motion, the peduncle was cut at the joint position and most of the fruits were harvested with its calyx. The stem training was done by binding the main stem to the pole with a elastic ring. The ring was split to be spread C-like figure. The ring was opened by the expanding motion of the end-effector. Then it was moved to the location of the main stem and the pole so that they were surrounded by the ring. By stopping the expansion, the ring clipped the stem and the pole by its elasticity. Defoliation experiment was also carried out. The leaf stalk was grasped by the end-effector and was broken by the twisting motion of the end-effector.