Seiichi Arima and Naoshi Kondo

Abstract:
Cucumber is one of the most popular vegetables cultivated in Japan. It must be harvested daily because of rapid maturation and the deterioration of quality in cucumbers harvested too late. We developed a cucumber harvesting robot using a visual sensor, manipulator, endeffector, and traveling device. To discriminate cucumbers from leaves and stems, we used a monochrome TV camera with 550 nm and 850 nm wavelength interference filters. After thresholding images, cucumbers were recognized morphologically. A seven degree-of-freedom (DOF) polar coordinate manipulator moved to a target cucumber and a harvesting end-effector grasped the top, detected the peduncle, and cut it. The manipulator and end-effector were trialmanufactured based on the cucumber's physical properties. A 4-wheel traveling device carrying the robot then moved to the next plant. Experiments verified the robot's feasibility in harvesting cucumbers.

Keywords: cucumber, manipulator, end-effector, image processing, plant training system