The rotary tillage model, which can predict the phenomenon of soil throw and required power in rotary tilling, was constructed around the discrete element method (DEM) in the previous paper (Hirasawa et al., 2014). In the current paper, pile shapes of soil tilled by two types of rotary tillers were estimated using this model. The comparison between the simulated and the experimental results indicated that this model was able to predict the pile shape of tilled soil. Additionally, this model was able to estimate the influence of mechanical specifications (rotary tiller width, rotary tiller blades arrangement and blade shape) on the root-mean-square (RMS) value of pile height distribution after tillage. The determination coefficient of the RMS value was 0.799.

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Ecofeed is feed prepared from unused food and contributes solving the problem of environment and the self-efficiency in feed in Japan. Nevertheless it has not been widely used because of its big nutrient composition variance. We developed low-price near-infrared spectrometer with high performance for the ecofeed to avoid time and money consuming chemical analysis. In this development, we collected dry-ecofeed samples from many areas and measured them by high-performance spectrometer. Using the measured data, we decided the specifications necessary for this development and we developed the instrument following these specifications. The performance of the instrument was almost as same as the high-performance spectrometer and the important components of moisture, crude protein and crude fat were measured within 1 minute.

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This paper presents results of an investigation of farm work technology characteristics. A chisel in a fertilizer-applicator ditcher was constructed to improve Welsh onion cultivation. When the fertilizer-applicator ditcher was opening a ditch, work rates were 1.31-1.76h/10 a, widths were 50-52cm, depths were 16-19cm, and the bottom surface widths were 19-20cm. Fertilizer positions were 6cm from the center at the bottom surface to horizontal. Depths at these positions were 2-3cm. Depths of the chise were 11cm. Amounts of rectangle board settlement at the center at the bottom surface showed a significant difference between test blocks with chisel and test blocks with no chisel. The work rate for planting showed no differences among test blocks. However, test block with chisel and double drill fertilize exhibited the best rate of right planting at 86%. Planting postures were improved by soil softening of the shallow phase, which disturbs drill fertilizers in an open ditch with a transplanter.

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We mounted our previously reported spraying robot on a magnetic-tape-guided vehicle positioned via QR codes. To eliminate double-processing of flowers, we gave the robot the capacity to record and compare flower cluster coordinates. We tested robot operation at night in a greenhouse with the 1st flower clusters of tomato. The robot was operated twice, 3 or 4 days apart, to cover the distribution of the flower blooming stage. The total processing time was 30s per flower cluster. The final success rate of spraying ranged from 92% to 100%. The fruit-set rate did not differ significantly between robot spraying and manual spraying ; the accuracy is high enough for practical use.

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To utilize rice straw culms, which are abundant in solubilized carbohydrates such as sucrose and starch, for bioethanol production, we developed a culm separator system that uses a flywheel-type cutter and a pneumatic separator. The system consists of a chopping part, a conveyor part, and a separation part that collects culms in a front bag and leaves in a rear bag. At 5.3m/s of the air flow, the system separated straws well, with an over-all separation efficiency of 0.84 and a work efficiency of 44.4kg/h.

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In order to raise efficiency and to reduce the costs associated with chemical-free, environment-friendly disinfection methods for rice seed, we propose a rice seed disinfection method that uses steam heating. This method aims to sterilize the surface of rice seeds with wet heat using steam condensation, and to simplify the cooling and drying process compared with the conventional hot water treatment.
To investigate the applicability of this method and determine the optimal conditions for rice seed disinfection, we examined the effects of heating air temperature, air humidity, air flow rate, and heating time on the sterilization rate and germination rate of rice seeds. We found that the optimal conditions were as follows : heating with an air temperature of 200°C, and wet bulb temperature of 80°C, a heating time of 2s, an air flow rate of 1.8m/s, and cooling by ventilation with ambient air for more than 60 s. Using these optimal conditions, the newly described disinfection method was as effective against blast and bacterial grain rot as the conventional hot water treatment.

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In this succeeding study, some refinements were made to develop the second prototype of a dibble fertilizer applicator (DFA2) to improve its delivering ability and field traveling performance. In addition, field tests were carried out to assess the performance of the DFA2 under different field conditions and to determine whether the growth and yield of winter head lettuce can be improved using the DFA2, in comparison to conventional broadcast fertilizer application. By optimizing component weights and locations, the weight of the DFA2 was reduced by half, from 30kg to 15kg, improving the field performance of the Chidorisan lettuce transplanter mounted with the applicator. The test results indicated that the DFA2 could accurately deliver coated fertilizer without residues within the discharge tube and that the reductions in the working rate and battery discharge time of Chidorisan when transplanting lettuce with dibble dressing were limited to 10% and 8%, respectively, in comparison to conventional transplantation. In addition, there is considerable potential for the use of starter fertilizer as part of an overall broadcast fertilizer to enable winter lettuce growers to increase profitability through increased marketable yields.

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