This paper provides details on the Advanced Plant Factory Research Center at Meiji University, which received a Grant-in-Aid from the Ministry of Economy, Trade and Industry for upgrading the factory facilities. The research aims to reduce the production cost at the plant factory and develop an environmentally sustainable production system. Further, details of the training programs conducted as education projects for the staff and to develop human resources in the plant factories are reported.

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Facilities for a closed type plant factory and semi-closed type plant factory were constructed at the Kurume campus of the NARO Kyushu Okinawa Agricultural Research Center and were funded by the Ministry of Agriculture, Forestry and Fisheries (MAFF). Research for low-cost and/or high value-added production of strawberry, leaf lettuce and sprouts is conducted at these facilities. This report introduces the design of these facilities and outlines of the research topics studied there as well as discusses activities related to human resource development and training program at these plant factories.

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This paper introduces the Plant Factory Research Center in Shimane University. First, the outline of the support and research center for the plant factory in Shimane University is reported. Then, research subjects, training programs for the plant factory is explained, and the contact information is indicated.

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We compared the total cost of greenhouse heating between a conventional oil-fired air heater and a hybrid system comprising an electric heat pump (rated at 49.2 W m^-2) and an oil-fired air heater (rated at 199.4 W m^-2) in identical rose greenhouses in Iwata city, Shizuoka, Japan. The greenhouses had a heat load coefficient of 3.7 W m^-2 K^-1. The average nighttime temperature in the hybrid-system greenhouse during August and September was 2.2°C lower than that in the oil-heater greenhouse owing to nighttime cooling by the heat pump. To maintain a minimum temperature of 18°C required an annual consumption of heavy oil for heating of 12.61 L m^-2 by the hybrid system and 33.49 L m^-2 by the oil heater. The annual consumption of electricity was 14.91 MJ m^-2 by the hybrid system and 1.13 MJ m^-2 by the oil heater. The total energy input for heating was 43.77 MJ m^-2 for the hybrid system and 81.62 MJ m^-2 for the oil heater. Using 3.79 as the coefficient of performance of the heat pump gave an estimated energy use of 78.19 MJ m^-2 for heating by the hybrid system, lower than the calculated value of 81.62 MJ m^-2; that is, the rated COP was exceeded. At an oil price of 65.8 yen L^-1, the annual running cost was 1645 yen m^-2 in the hybrid-system greenhouse and 2162 yen m^-2 in the oil-heater greenhouse. The annual cut rose production was 712.7 g per plant in the hybrid-system greenhouse and 643.2 g per plant in the oil-heater greenhouse. In particular, production in the hybrid system was 53% higher in August and September, when nighttime cooling was operated. Overall, the hybrid system resulted in savings of 46% of input energy and about 24% of energy costs.

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This paper presents a procedure and the results of obstacle-avoidance control of a stationary strawberry-harvesting robot to be used with circulating-type movable bench cultivation. The stereovision unit detects mature and immature fruits from beneath the bench while being conveyed laterally. Based on the positional relation between them, the most appropriate direction for the end-effector approach is determined to avoid collision with immature fruits. The end-effector approaches along the calculated direction and controls its posture at 120 mm and 80 mm front of the target fruit, using visual feedback so as to match the roll angle of the end-effector with the peduncle angle, as estimated using a hand-eye camera. In the peduncle detection procedure, green LED lights are used to emphasize the calyx and peduncle. The proposed stereovision algorithm showed a success rate for detection of the appropriate approach angle of 89-93%. In the insertion test, the hand-eye camera was able to recognize the target peduncle at a success rate of 77-80% by facing the fruit from the most appropriate approach angle, and the end-effector was able to insert a peduncle at a success rate of 73-78%. The end-effector approach along the appropriate approach angle was confirmed to be the effective way to avoid collision with immature fruits, although several multiple insertions were observed. Our proposed procedure proved to work functionally together with the lateral movement of the movable bench.

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