著者

尾田 十八 坂本 二郎 坂野 憲一

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 A編 (ISSN:03875008)

巻号頁・発行日

vol.71, no.701, pp.89-94, 2005-01-25 (Released:2011-08-16)

参考文献数

6

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A woodpecker strikes its beak toward a tree repeatedly. But, the damage of brain or the brain concussion doesn't occur by this action. Human cannot strike strongly the head without the damage of a brain. Therefore, It is predicted that the brain of a woodpecker is protected from the shock by some methods and that the woodpecker has the original mechanism to absorb a shock. In this study, the endoskeltal structure, especially head part structure of woodpecker is dissected and the impact-proof system is analyzed by FEM and model experiment. From the results, it is obvious that the woodpecker has the original impact-proof system as the unique states of hyoid bone, skull, tissue and brain. Moreover it is considered that woodpecker has the advanced impact-proof system relating with not only the head part but also with the whole body.

著者

茅原 崇徳 岩原 和宏 坂本 二郎

出版者

一般社団法人 日本人間工学会

雑誌

人間工学 (ISSN:05494974)

巻号頁・発行日

vol.54, no.Supplement, pp.2H2-1, 2018-06-02 (Released:2018-07-10)

著者

酒井 忍 尾田 十八 米村 茂 坂本 二郎

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 A編 (ISSN:03875008)

巻号頁・発行日

vol.73, no.734, pp.1177-1182, 2007-10-25 (Released:2011-03-02)

参考文献数

10

被引用文献数

2 1

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In the United States and Japan, baseball is a very popular sport played by many people. However, the ball used is hard and moves fast. A professional baseball pitcher in good form can throw a ball at up to 41.7 m/s (150km/hr). If a ball at this speed hits the batter, serious injury is quite likely. In this paper we will describe our investigations on the impact of a baseball with living tissues by finite element analysis. Baseballs were projected at a load cell plate using a specialized pitching machine. The dynamic properties of the baseball were determined by comparing the wall-ball collision experimentally measuring the time history of the force and the displacement using dynamic finite element analysis software (ANSYS/LS-DYNA). The finite element model representing a human humerus and its surrounding tissue was simulated for balls pitched at variable speeds and pitch types (knuckle and fast ball). In so doing, the stress distribution and stress wave in the bone and soft tissue were obtained. From the results, the peak stress of the bone nearly yielded to the stress caused by a high fast ball. If the collision position or direction is moved from the center of the upper arm, it is assumed that the stress exuded on the humerus will be reduced. Some methods to reduce the severity of injury which can be applied in actual baseball games are also discussed.

著者

茅原 崇徳 宮﨑 太志 坂本 二郎

出版者

一般社団法人 日本人間工学会

雑誌

人間工学 (ISSN:05494974)

巻号頁・発行日

vol.55, no.Supplement, pp.1F3-6, 2019-06-15 (Released:2019-07-31)

著者

尾田 十八 山崎 光悦 坂本 二郎 北山 哲士 酒井 忍 金井 亮 李 鵬 李 鵬

出版者

金沢大学

雑誌

基盤研究(A)

巻号頁・発行日

2006

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本研究は,自然・生態系と調和した新しい材料,構造,機器,システム等の創生法を,生物に学ぶことによって確立することを目的としている.その方法は多様な生物の中で,特異性を有する生物にまず注目する.本研究では動物の例として繰返し衝撃負荷に耐える「キツツキ」を,植物の例としては,軽量であるが不燃性を示す「桐材」に注目した.そしてこれらの特性がどのようなメカニズムによって生じているのかを,主として力学的視点より明らかにした.これらの結果と,代表者らがすでに行って来ている竹や卵殻の構造・組織分析結果を含め,新しい構造設計および材料設計法の基本原理を提示した.

著者

尾田 十八 坂本 二郎 坂野 憲一

出版者

一般社団法人 日本機械学会

雑誌

北陸信越支部総会・講演会 講演論文集 2004.41 (ISSN:24242772)

巻号頁・発行日

pp.155-156, 2004-03-01 (Released:2017-06-19)

著者

尾田 十八 坂本 二郎 坂野 憲一

出版者

一般社団法人日本機械学会

雑誌

日本機械学会論文集. A編 = Transactions of the Japan Society of Mechanical Engineers. A (ISSN:03875008)

巻号頁・発行日

vol.71, no.701, pp.89-94, 2005-01-25

参考文献数

6

被引用文献数

2

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A woodpecker strikes its beak toward a tree repeatedly. But, the damage of brain or the brain concussion doesn't occur by this action. Human cannot strike strongly the head without the damage of a brain. Therefore, It is predicted that the brain of a woodpecker is protected from the shock by some methods and that the woodpecker has the original mechanism to absorb a shock. In this study, the endoskeltal structure, especially head part structure of woodpecker is dissected and the impact-proof system is analyzed by FEM and model experiment. From the results, it is obvious that the woodpecker has the original impact-proof system as the unique states of hyoid bone, skull, tissue and brain. Moreover it is considered that woodpecker has the advanced impact-proof system relating with not only the head part but also with the whole body.

著者

坂本 二郎 小林 佳介 北山 哲士 清水 信孝

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00212-17-00212, 2017 (Released:2017-10-25)

参考文献数

27

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An optimum design method for determining the cross-sectional sizes of thin steel plate columns used for steel framed house was developed to maximize their buckling strength under a constraint of constant volume using evolutionary computing and cold forming. Buckling analysis was performed by finite strip method (FSM) that can analyze the buckling loads of local, torsional, and total buckling within less computational time. Differential evolution (DE) was used for the optimization algorithm because it is a fast and reliable method for non-linear, non-convex, and multimodal optimization problems. In this research, an optimum design method is proposed, which combines DE and FSM to achieve an efficient global optimum design considering comprehensive buckling modes. This method was applied to overcome the optimum design problems of the thin steel plate columns with a lip channel cross-section. Normal axial compression capacity (Nc) of the column under a constant volume was maximized by considering design variables such as web height, flange width, and lip length of the cross-section. The search performance of the optimization method was evaluated by obtaining an objective function (1/Nc), which was calculated at the lattice points of the design variables. The optimum design point obtained by the optimization method included a global minimum point of the objective function surface, hence ensuring the validity of the proposed method. Furthermore, the optimum design problem was solved under the deformation constraint by considering connection to the wall panels for the column length of 1000 mm, 2000 mm, and 3000 mm. Optimum designs with the open profile cross-section was obtained for all the abovementioned column length. The optimum designs obtained by the proposed method can be used for practical purposes because of their open profiled cross-section and can be produced by cold forming.

著者

小久保 慎弥 北岡 雅哉 坂本 二郎 不島 健持 小林 優

出版者

一般社団法人 日本機械学会

雑誌

年次大会

巻号頁・発行日

vol.2012, pp._J025022-1-_J025022-4, 2012

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In orthodontics medical treatment the diagnostic system which simulates movement of the tooth by orthodontic force is required in order to perform orthodontics medical treatment more easily for a short period of time. In this research, teeth finite element model in consideration of the mechanical property of the periodontal membrane was developed and the simulation procedure of the bone resorption which occurve in an alveolar bone was proposed. As a result, it was ensured that teeth finite element model considering the characteristic of the periodontal membrane was effective. By using a bone resorption simulation procedure, the possibility of representation of the bone resorption in an alveolar bone was sugested.

著者

坂本 二郎

出版者

一般社団法人日本機械学会

雑誌

日本機械学會誌 (ISSN:00214728)

巻号頁・発行日

vol.106, no.1015, 2003-06-05