This paper describes the development of a movable strawberry-harvesting robot that can be mounted on a travel platform, along with its practical operation in a greenhouse. The harvesting robot can traverse and enter an adjacent path and picking is performed with the travel platform halted on the travel path. Machine vision is used to detect a piece of red fruit and calculate its position in the three-dimensional space, whereupon its maturity level is assessed according to an area ratio determined by classifying the whole fruit into three areas: ripe, intermediate, and unripe area fractions. Sufficiently mature fruit are picked by the end-effector by cutting the peduncle. During operational tests in a greenhouse, our machine vision algorithm to assess maturity level showed a coefficient of determination of 0.84. Setting the maturity level parameter at 70 or 80% resulted in higher shippable fruit rates than the setting of 60%, because small unripe fruit positioned in front of larger ripe fruit were successfully skipped in the former case. Our results showed that a higher shippable fruit rate could be achieved later in the harvest season, reaching 97.3% in the test in June. The successful harvesting rate and work efficiency were 54.9% and 102.5 m h -1 , respectively.
This paper describes a strawberry-harvesting robot, a packing robot, and a movable bench system. The harvesting and packing operations in strawberry production require harder, more time-consuming work compared to other operations such as transplanting and chemical spraying, making automation of these tasks desirable. Since harvesting and packing operation account for half of total working hours, automation of these tasks are strongly desired. First of all, based on the findings of many studies on strawberry-harvesting robots for soil culture and elevated substrate culture, our institute of the Bio-oriented Technology Research Advancement Institution and Shibuya Seiki developed a commercial model of a strawberry-harvesting robot, which is chiefly composed a cylindrical manipulator, machine vision, an end-effector, and traveling platform. The results showed an average 54.9% harvesting success rate, 8.6 s cycle time of picking operation, and 102.5 m/h work efficiency in hanging-type growing beds in an experimental greenhouse. Secondly, a prototype automatic packing robot consisting of a supply unit and a packing unit was developed. The supply unit picks up strawberries from a harvesting container, and the packing unit sucks each fruit from calyx side and locates its orientation into a tray. Performance testing showed that automatic packing had a task success rate of 97.3%, with a process time per fruit of 7.3 s. Thirdly, a movable bench system was developed, which makes planting beds rotate in longitudinal and lateral ways. This system brought high density production and labour saving operation at a fixed position, such as crop maintenance and harvesting. By setting up the main body of a strawberry-harvesting robot on working space, unmanned operation technique was developed and tested in an experimental greenhouse. Field experiments of these new automation technologies were conducted and gave a potential of practical use.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.