This paper clarifies an improvement to the enzymatic saccharification and volume reduction of rice straw pellets. During pelletization, rice straw is triturated under high temperatures and pressures. The saccharification rate is 36% and improves than crushing alone. In addition, the bulk density of the pellet is 0.64g per cm³, over four times as much as that of a rice straw roll bale. The collection and transportation cost of the conventional and pelletization system were estimated at 14.4 and 17.8yen per kg, respectively. This didn’t lead to a reduction in overall cost because of the higher cost of pelletization, however, the reduction of the secondary transport and loading-unloading cost was accepted by the volume reduction of rice straw.

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The previous paper constructed a rotary tillage model developed through the discrete element method (DEM) capable of predicting the phenomenon of soil throw and the power required in rotary tilling. In this paper, this model was used to estimate soil throw and axle torque in rotary tilling with two different shapes of rotary blades. A comparison of the experimental measurements and those predicted by the model revealed that this model was quite accurate in predicting the distribution velocity of soil particles. In addition, the model proved capable of predicting the rotary axle torque within a range of 81.9% to 113%.

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The main objective of this study was to develop and evaluate an ordinal feed-forward control system for seeding depth regulation applied for conservation tillage systems utilizing a conventional seeder. The conventional seeder was fitted with a hydraulics-based control system that placed seeds at the correct seeding depth based on the soil profile. Field tests conducted in four years evaluated the seeding depth performance of the control system under conservation tillage systems. The results of this study indicate that seeding depth regulation was effective at root mean square error (RMSE) of 4.79mm seeding depth with a mean delay of 0.3s with a standard deviation (SD) of 0.16s. The control system was capable of handling soil surface undulations 75.0mm above and below the soil surface at 1.0m/s tractor speed. Field tests showed significant differences on the seeding depth between controlled and uncontrolled rows.

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We designed a temporary holder, a peduncle grip-type package, and related packaging equipment, to reduce damage to the fruit and minimize packaging workload. Our packaging equipment can automatically and simultaneously place six strawberries into a peduncle grip-type package from temporary holders. To minimize damage to the strawberries, both the packaging and the equipment grips the peduncle of each strawberry. The packaging equipment shows an over 90% success rate and its sequence of actions takes about 27 seconds.

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We have developed a rotary type nozzle to peel welsh onions that has a lower demand for compressed air, thus allowing the use of a smaller air compressor. Performance tests of our prototype peeler mounted with our rotary type nozzle revealed a 20% better, working efficiency than existing peelers, while requiring only 1/3 the volume of compressed air. We have also developed a diameter-based sorting device for welsh onions that can be mounted on our peeler. Performance test showed that it was about 80% accurate.

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We have made a third prototype peeler for welsh onions, mounted with our rotary type nozzle and sorting device. Field trials showed its peeling efficiency to be 2-31% better than conventional peelers, the compressed air requirement to be reduced by 46-83%, and a 33-71% cut in power consumption by the air compressor. A comparison between the efficacy of our sorting device and that of skilled workers showed an approximately equal level of accuracy.

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Sorting yield decreases if scab-damaged wheat kernels are removed by conventional sorting systems because of the revised agricultural product inspection standard. The purpose of this study was to investigate the adaptability of an optical sorter to remove scab-damaged wheat kernels to increase sorting yield. The results showed that near-infrared transmittance of scab-damaged wheat kernels was apparently lower compared with that of nondamaged wheat kernels. Thus, the optical sorter equipped with a near-infrared sensor could remove scab-damaged wheat kernels. Sorting yield can be increased by using a wheat grain sorting system with an optical sorter built into the return process of the gravity separator.

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A balanced trimmer was developed for safe and usability. In this study, we attempted to improve its vibration characteristics. The handle grip was found to be subject to heavy vibrations in the high-frequency range of 100 to 250Hz, which were significantly influenced by the handle pipe structure. To reduce these vibrations without increasing the weight of the trimmer, we attempted to decrease the resonance frequency and response level by the use of a thinner handle pipe, attachment of a small mass, and by modifying the rubber bushing to increase the amount of damping. These measures led to a large decrease in high-frequency handle vibrations, without any increase in the total weight or in low-frequency vibrations.

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