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Volume 63, Issue 2
Displaying 1-15 of 15 articles from this issue
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M. KARAHASHI2001 Volume 63 Issue 2 Pages 1-2
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
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Kunio SATO2001 Volume 63 Issue 2 Pages 4-7
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
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Y. ABE2001 Volume 63 Issue 2 Pages 8-9
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
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Kunio SATO, Makoto HOKI, Masaaki YATSUHASHI, Harry G. GIBSON2001 Volume 63 Issue 2 Pages 23-28
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThis investigation is to develop an isolated word recognition technique in the presence of large amounts of engine noise for the purpose of controlling a tractor. The profiles of consonants and vowels are measured as spectra integrals and maxima of cepstrum respectively. These profiles are introduced to a neural network to identify the categories of words uttered by an operator. A high-pass cutoff needed for the spectrum integral in order to reduce the noise interference, is also discussed. To confirm the effectiveness of the system developed, online control experiments were carried out with the tractor at rest and favorable results were achieved.View full abstractDownload PDF (2817K) -
Prathuang USABORISUT, Masayuki KOIKE, Akira YODA, Yoshisada NAOASAKA, ...2001 Volume 63 Issue 2 Pages 29-38
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe loading and loading-free processes of a cyclic torsional shear test were conducted to investigate and simulate the soil behavior induced by machinery services in the field during crop production. The results showed that the corresponding torsional shear deformation was found under the cyclic loading process accompanied by the development of pore water pressure. On the other hand, an increase of bulk density and axial strain occurred on the loading-free process and seemed to be affected by the development of pore water pressure in the preceding cyclic loading process. A comparison with the normal cyclic torsional shear loading test was also made in order to distinguish the specific soil behavior under both loading modes. Moreover, the effects of loading magnitude, amount of the number of cyclic loading in the loading set and bulk density were clarified. Also, the stress path tracing in the state space was investigated to help explain the soil behavior under loading and loading-free processes.View full abstractDownload PDF (1383K) -
Kenji IMOU, Tsuguo OKAMOTO, Yutaka KAIZU, Hiroki YOSHII2001 Volume 63 Issue 2 Pages 39-46
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSA high-resolution ultrasonic Doppler speed sensor was developed to improve the accuracy of speed measurement for autonomous driving systems. The prototype sensor consists of ultrasonic transducers of 200kHz and electronic circuits of a preamplifier, a tuned amplifier, a frequency multiplier and so on. The frequency of received signal from the ground was multiplied by 5 to improve the resolution and mixed with a reference signal of 950kHz. The reference signal was generated from the same oscillator as used for the transmission signal using a frequency synthesizer. The speed sensor was tested on five types of model ground surface using a linear actuator with a 4m distance of motion. The sensor could measure the speeds of both forward and reverse motions with relatively high accuracy, and could measure speeds of as low as 10mm/s.View full abstractDownload PDF (5108K) -
Investigation of Cultivation for Radish ProductionShu-huai ZHANG, Teruo TAKAHASHI, Hiroshi FUKUCHI, Kouichi SAGA2001 Volume 63 Issue 2 Pages 47-52
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSHarvesting, preparing and thinning are time-consuming and labor-intensive components of the radish production. The automated operation of vegetable harvesting and preparing have been improved by the development of commercial machines. However, the vegetable thinning continues to be a manual effort except using the precision sowing machines. The objective of the research is to develop a robotic system for thinning of radish seedling. In this paper, a new cultivation method was proposed. In the new method it was suggested what sowing way is suitable to robotics and when it is best time to thin seedling. Radish growth was also investigated by using the new method to thin seedling, compared with traditional cultivation. The result showed that the new method had no adverse effect on radish growth.View full abstractDownload PDF (5699K) -
Kenji IMOU, Hiroki YOSHII, Tsuguo OKAMOTO, Yutaka KAIZU2001 Volume 63 Issue 2 Pages 53-59
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSUsually, a narrow beam of high-frequency ultrasonic wave is used for ultrasonic Doppler ground speed sensors. However, serious errors may be caused especially on smooth ground surfaces, because the received signal will be weak due to the high attenuation ratio and the small insonified area of the narrow sonic beam. In order to solve the problem, an ultrasonic Doppler speed sensor was developed using transducers operating at a relatively low frequency of 40kHz. The transmitted sonic wave had a high intensity and a broad directivity. An offset parabolic reflector was used to control the traveling directions of sonic waves instead of a narrow beam. The experimental results demonstrated the effect of the reflector. Even for a smooth ground such as a concrete surface, the sensor showed almost the same performance as that for rough ground surfaces.View full abstractDownload PDF (2723K) -
Comparison of desiccator and film storageWin win Myint, Yoshitaka MOTONAGA, Atsushi HASHIMOTO, Takaharu KAMEOKA2001 Volume 63 Issue 2 Pages 60-68
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSTo obtain the respiratory characteristic of agricultural product, the controlled atmospheric storage was conducted by using the desiccator at 5°C, 10°C and 25°C. As the experimental sample, mature green tomatoes and red ripe tomatoes were used. In a closed system, ripening was inhibited for tomato stored in low oxygen atmosphere, and the pseudo-periodic stop was observed at the critical respiration. It was confirmed that at 5°C tomatoes suffered chilling injury in the low oxygen atmospheric storage. Moreover, the oxygen permeability of film package was designed from the critical respiration rate calculated from the data by using the desiccator and it was examined on the effective storage desiccator. The results indicated that the change in surface color of tomato in the packaging film was inhibited. And it was confirmed that both the desiccator and film in the same storage condition showed the same tendency in the storage effect. Therefore, it is also confirmed that the packaging film with oxygen permeability 4, 300ml/m2·24h could be applied for the agricultural products.View full abstractDownload PDF (3051K) -
Prediction of Thrust, Rolling Resistance and Traction by Three-dimensional ModelXiu Lun WANG, Nobutaka ITO, Koji KITO2001 Volume 63 Issue 2 Pages 69-75
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSIn order to improve the performance of tracked vehicle, dimensions of grouser shoe of tracked vehicle were analyzed for its optimum tractive performance in this study. To investigate the effects of the grouser thickness ratio and the grouser height on the tractive performance, thrust, rolling resistance and traction generated by the grouser shoe were analyzed by using threedimensional model of soil shearing by changing in grouser thickness ratio and grouser height. According to the results of the theoretical and computer simulation analysis on the grouser shoe dimensions and tractive performance, it was concluded that maximum traction could be obtained when the grouser thickness ratio was 0.1 and the grouser height was 6.5cm for the given soil. It is clear that there were remarkable effects of grouser thickness and grouser height on tractive performance of the tracked vehicle.View full abstractDownload PDF (1038K) -
Basic Characteristics of a Dual Fueled CGS Operated with Biogas and Gas OilJong-Soo PARK, Kohta ISHII, Hideo TERAO2001 Volume 63 Issue 2 Pages 76-83
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe purpose of the study is development and investigation about basic performance of the system operation on a dual fueled cogeneration system (CGS), which is operated with Biogas and gas oil. As often seen in dual fueled CGS performance, the electric generating efficiency was obtained about 26%. Methane contained in the biogas could not burn completely at lower load, and it was discharged into exhaust gas. Considerable amount of the methane burned in the exhaust pipe, and the heat recovery ratio was 42% on heat balance. As a result, the total heat efficiency, which is a summation of generating efficiency and heat recovery efficiency reached to about 68%. The supply of biogas into the engine reduces smoke density and NOx concentration in exhaust gas.
At lower load, methane burned slowly and large portion of it was discharged without burning. To solve this problem, the development of the measures, which promote the complete combustion of methane, is important.View full abstractDownload PDF (3209K) -
Detection of Seed Blobs in Tray-Cells by a New Grid MethodMasateru NAGATA, Zacharia M. MGANILWA, Hongyong WANG, Masafumi MITARAI2001 Volume 63 Issue 2 Pages 84-91
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSA grid method to detect the existence of vegetable seeds into the tray-cells after the seeding operation was developed. Its features include generation of windows, noise suppression and grid operators. Windows are generated and processed at the cavities of the tray instead of processing the whole image of the tray. The image noises are suppressed by using local average filter kernel operation. Then the seed blobs are detected using grid operators. Judgement to whether the blob represented a seed or noise was carried out according to continuity of the grids that represent an object in the 8-or 16-neighborhood. To test the performance of the developed grid method, morphological features of the seeds and noises were extracted and analyzed. The results showed that the grid method suppressed the image noises by 76.9% and successfully detected the seed blobs. The detection accuracy was 100% for cucumber, melon, lettuce, eggplant and green pepper seeds, and was 99.2% for tomato seeds. Hence, the usefulness of the method to detect the existence or non-existence of seeds into the tray-cells was confirmed.View full abstractDownload PDF (5986K) -
Supplemental Seeding Method Using Image ProcessingZacharia M. MGANILWA, Masateru NAGATA, Hongyong WANG, Takayoshi AKINAG ...2001 Volume 63 Issue 2 Pages 92-99
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThis paper describes the study of a supplemental seeding method using machine vision for inspecting the seed miss in a moving tray and instantly plant the seeds into the empty cavities. The method consisted of the supplemental seeding software and hardware components. The software component had the program for detecting seeds and controlling the supplemental seeding device using image processing. The hardware composed of a supplemental seeding device, which was fitted on a commercial seeder, control box, CCD camera, a personal computer, frame grabber and an I/O board. The detecting software of the supplemental seeding method could detect the seeds in a moving tray at an accuracy of 100% for cucumber, melon, coated lettuce, eggplant and green pepper seeds, and 99.93% for tomato seeds. The image processing signals precisely controlled the supplemental seeding device such that it could plant the seeds into the empty cavities at an accuracy of more than 99% with seeding time of 0.6s per cavity. Therefore, the usefulness of the studied method was recognized for automating the production of plug seedlings.View full abstractDownload PDF (2744K) -
An Optimization of Work AllocationKatsuaki OHDOI, Akira OIDA2001 Volume 63 Issue 2 Pages 100-108
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSTo find the optimum farm work schedule as a part of the optimum agricultural mechanization system, an effective method was developed. The method to find the optimum route of a farm machine that visits some fields scatterd in an area was described in the last paper. In this paper, a method to efficiently allocate the farm work for a group of machines is described. The working time and the field position were considerd as subjects of evaluation, and the best situation was supposed that each machine had a farm work with an equal working time and the shortest moving distance. Genetic Algorithm was adopted as the method to optimize the farm work schedules, and the coding method was improved to apply it to the case using more than two machines.View full abstractDownload PDF (2903K) -
System Component and Concept of Task Planning for Teat Cup AttachmentMitsuru HACHIYA, Akira HIRATA, Takashi KUWANA, Yoshitaka IBARAKI, Yosh ...2001 Volume 63 Issue 2 Pages 109-117
Published: March 01, 2001
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe aim of this study is to develop a milking robot system that satisfies the necessary requirements to attach teat-cups for cows automatically in stanchion stall barns. The prototype system consists of three components, a mobile truck that travels on rails, the cow's body positioning arm from the truck by roller, and the automatic milking unit mounted on one end of the cow's body positioning arm. The teat-cup manipulator is an articulated robot provided with three degrees of freedom in horizontal planes, where an AC servomotor controls each axis. A pneumatic gripper is used for the end-effector to hold the teat cup, and a local sensor with the area, 80mm×66mm, a matrix of 10 infra-red light beams is arranged across the top of the end-effector to detect the teat and allow correction of the robot position to centralize the cup on the teat. For attachment the co-ordinates from the database are used to provide the approximate location for each teat. And then positional commands are sent to the servo drivers at intervals of 20ms via the positioning pulse distributor so that the deviation in less than the set value.View full abstractDownload PDF (5532K)
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