著者

沢 俊行 唐沢 明浩 原田 容一 清水 章弘

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C編 (ISSN:03875024)

巻号頁・発行日

vol.52, no.476, pp.1455-1461, 1986

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The design method of bolted joints with gaskets is almost based on experience, and the sealing performance is not made clear by theoretical analyses. In the present paper, discussion is made on the distribution of contact stress in the bolted joints fastened with tap bolts, when a clamped part with a gasket is the cover of a pressure vessel and a circular flange. The distribution of contact stress is analyzed as a three-body contact problem, using the three dimensional theory of elasticity. Moreover, the contact stress is measured by means of ultrasonic-waves. In addition, the force ratio (the ratio of an increment of the bolt axial force to an external load) and the maximum stress caused in bolts taking account of a bending moment are analyzed. For verification, experiments are carried out, and the analytical results are in fairly good agreement with the experimental ones.

著者

小関 敏彦

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会東北支部秋季講演会講演論文集 2005.41 (ISSN:24242721)

巻号頁・発行日

pp.1-4, 2005-09-09 (Released:2017-06-19)

著者

沖野 友洋 永田 恵輔 高野 純一 小林 秀敏

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.87, no.902, pp.21-00073, 2021 (Released:2021-10-25)

参考文献数

19

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The crash safety structure of the railway vehicles is important as one of the safety measures against the train crews and the passengers in the event of a collision accident. It is impractical to perform collision testing many times using the actual train unit to design the crash safety structure, whereby the numerical simulation is effective and it is important to validate the analytical accuracy. However, there are few studies of collision tests and numerical simulations using actual size carbody structures according to Japanese design standards, and even fundamental data have not been sufficiently obtained. Therefore, firstly, the authors performed the collision test of an actual-size partial stainless-steel carbody structure of a railway leading vehicle against a rigid wall and finite element analysis under the same condition as the test for the purpose of validating and improving the analytical accuracy of numerical simulation. Secondly, we carried out the collision test of the same carbody structure of a railway leading vehicle against a typical large dump truck in Japan and obtained the fundamental data such as the time histories of the impact compression load and the acceleration of the carbody structure as well as the deformational and fractural behavior of them. We also performed FE analysis under the same condition as the experimental test and compared the numerical result to the experimental one. As a result, the numerical result was consistent with the experimental result. Finally, we expanded the partial carbody structure model to a single carbody model and carried out the collision analysis of it against a large dump truck. Thereby, the impact deformation and fracture behavior of the railway carbody under the actual level-crossing accident were estimated.

著者

宮崎 恵子 平田 宏一

出版者

一般社団法人 日本機械学会

雑誌

交通・物流部門大会講演論文集

巻号頁・発行日

vol.2007, pp.55-56, 2007

著者

蔭山 雅洋 田中 成典 山本 雄平 鳴尾 丈司

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.87, no.902, pp.21-00158, 2021 (Released:2021-10-25)

参考文献数

33

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In recent years, as measurement devices have advanced due to sensor and information technology, we have been able to measure bat swing data just after baseball impact. Therefore, the purpose of this study was to examine the characteristics of a batter’s swing using batting skill assessments from baseball coaches with significant experience. Finally, the practicality and effectiveness of baseball coaching methods, particularly for batting, were verified through this study. The subjects were 25 male university baseball players (age: 19.8 ± 1.0 yrs, body height: 174.5 ± 5.4 cm; body weight: 72.8 ± 5.1 kg). The participants were instructed to hit the ball placed on a tee stand. Nine types of tee-batting positions (course / height) were set for each participant depending on the upper and lower limits of the strike zone according to the baseball rules. Our main findings were as follows: 1) The swing characteristics (Depth: swing time and vertical bat angle, Height: head speed, rolling angular velocity, bat radius of rotation, horizontal bat angle, and vertical bat angle, Course: rolling angular velocity) varied with respect to ball positions, 2) Through batting skill assessment by two baseball coaches with significant experience, a good batter’s swing can be characterized as high bat speed, short swing time, and high efficiency of rotational movement around the vertical axis. Additionally, the coaches suggested that for a good batter’s swing, the vertical bat angle should be stable and smaller than 9°. These results provide useful information on assessment of bat swing training methods and exercises to hit the ball to different positions. Furthermore, this study can aid baseball coaches and/or players to objectively analyze a bat swing of a player.

著者

島野 諒 戸森 央貴 宮永 隆史 中村 太郎

出版者

一般社団法人 日本機械学会

雑誌

ロボティクス・メカトロニクス講演会講演概要集 2014 (ISSN:24243124)

巻号頁・発行日

pp._2A1-X01_1-_2A1-X01_4, 2014-05-24 (Released:2017-06-19)

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Recently, the development of mobile robots is actively pursued. These robots are expected to have high mobility, allowing them to work in various scenarios such as rescue and exploration. Therefore, we focused on the hexapod robot for stable operation in an irregular terrain. We developed a leg using the parallel linkage mechanism and pneumatic rubber artificial muscles, and constructed a model of the legs. The model reproduced the experimental result. Then, we developed improved hexapod robot which can support its weight mechanically using these legs. Furthermore, the robot is assembled all system for walking. Also, we demonstrated that the robot could walk with high load of 300[N].

著者

長山 尭拓 石原 ひかる 奥井 学 山田 泰之 中村 太郎 名波 正善 岡村 成浩 原 以起

出版者

一般社団法人 日本機械学会

雑誌

年次大会 2016 (ISSN:24242667)

巻号頁・発行日

pp.S1510201, 2016 (Released:2017-06-19)

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To achieve dynamic motion, such as jumping and running, generating large instantaneous force and decreasing impact force at the time of the landing are needed. However, when increasing the instantaneous force of actuators such as motors and hydraulic actuators, the weight of robot also tend to increase. Therefore, in this study, we focused on the variable viscoelastic element with the human muscle. In this paper, we developed a bipedal jumping robot with variable viscoelastic joints. In this robot, we adopted straight-fiber-type artificial muscle as a variable elastic element and the magnetorheological fluid (MR) brake as a variable viscous-friction element. Moreover, we conducted the bending and stretching operation experiment by this robot. In this experiment, we used the experimental parameters which were determined based on human bending and stretching operation. As a result, it was confirmed that this robot realized the bending and stretching operation.

著者

安藤 真吾 戸森 央貴

出版者

一般社団法人 日本機械学会

雑誌

ロボティクス・メカトロニクス講演会講演概要集 2018 (ISSN:24243124)

巻号頁・発行日

pp.1P2-H10, 2018 (Released:2018-12-25)

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Pneumatic rubber Artificial muscle (PAM) has high back drivability and high output. However, PAM's Repetitive durability is low and not less well understood. Observing broken PAM which was made of carbon and latex rubber, there were breakage of fiber in it. Thus, we focused Aramid fiber that has high maximum shearing stress and abrasion resistance. Then, we compared load characteristics and repetitive durability between PAMs using carbon fiber and aramid fiber. Experimental result showed that load characteristic of PAM using aramid fiber is equal to PAM using carbon fiber. Furthermore, repetitive durability of PAM using Aramid fiber is 6times better than one using carbon fiber.On the other hand, we tried to develop reparable PAM using thermoplastic elastomer (TPE). And load characteristic experiment and repetitive durability experiment were conducted. As a result, load characteristic of PAM using TPE was equal to previous PAMs. For future works, we are planning to simulate PAM from the viewpoint of material mechanics. Meanwhile, we are planning to improve repetitive durability of PAM using TPE.

著者

石黒 久雄 吉田 真 太田 正廣

出版者

一般社団法人 日本機械学会

雑誌

バイオフロンティア講演会講演論文集 2008.19 (ISSN:24242810)

巻号頁・発行日

pp.56-57, 2008-09-22 (Released:2017-06-19)

著者

荻野 貴司 秋元 俊成 友納 正裕 松元 明弘

出版者

一般社団法人 日本機械学会

雑誌

ロボティクス・メカトロニクス講演会講演概要集

巻号頁・発行日

vol.2008, pp._2P2-C05_1-_2P2-C05_3, 2008

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For the future cohabitation of humans and robots, we are making research on home use robots, where positions of robot, human and environment must be precisely recognized. We used omnidirectional mobile robot with laser range sensor for this purpose, and made experiments on map building and human following. First, we adopted scan matching algorithm for the localization of mobile robot in the stable environment, and confirmed the performance of the map building by experiments. Next, we applied this algorithm to the mixed environment of human and robot, and succeeded to extract human motion and robot motion along with the map building at the same time. We implemented the motion extraction algorithm for the human following application.

著者

吉田 敬介 黒河 周平 松枝 嘉明 坂 清次

出版者

一般社団法人 日本機械学会

雑誌

年次大会講演論文集

巻号頁・発行日

vol.2004, pp.427-428, 2004

被引用文献数

1 1

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An experience-oriented safety education for both university students and staff members was attempted in Kyushu University, by introducing a practical education program for company employee designed by a training and education company. In this paper firstly the reason why such a type of education is needed for university is described. And then outline and executed result of the program, which consisted of two experience-oriented education programs and was the most suitable as the first attempt at the university, is explained: one is 'catching-into-the-roller experience' with a simulator, the other is 'combustion and explosion experience'. Finally problems to be solved to grow this program are discussed, based on the questionnaire to the participants who finished this prqgram,

著者

高橋 陽一 末永 陽介 北野 三千雄 工藤 めぐみ

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 B編 (ISSN:03875016)

巻号頁・発行日

vol.71, no.712, pp.3046-3052, 2005

被引用文献数

2

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Response of a cylindrical premixed flame to periodic concentration fluctuation was investigated. The flame was formed in a porous cylinder by percolating the mixture uniformly through the cylinder wall. The burner used here was devised so as to fluctuate the mixture concentration (equivalence ratio) only in the radial direction of the flow (vertically to the cylindrical flame surface) without varying the flow field. With this burner the time variations of burning velocity, burnt gas temperature and flame luminosity were measured for the lean methane-air mixture in the range of fluctuation frequency from 3 Hz to 50 Hz, and the results were examined from the viewpoint of flame curvature effects. The results show that the variation width of the burning velocity of the dynamic flame is larger than that of the static flame corresponding to the concentration fluctuation. Burnt gas temperature and flame luminosity also exhibit similar tendencies. The magnification ratio of the variation width depends on the flame curvature and the large flame curvature makes the flame sustainable even for the mixture leaner than the flammability limit of the static flame.

著者

宮下 敬宏 堀川 優紀子 萩田 紀博 K. Narayanan Vishnu 小泉 智史 亀井 剛次

出版者

一般社団法人 日本機械学会

雑誌

ロボティクス・メカトロニクス講演会講演概要集

巻号頁・発行日

vol.2018, pp.1P2-D09, 2018

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<p>Development for safety autonomous mobility navigation system that deal with low speed vehicles, such as wheel chair, guidance robot and transportation robot is introduced. Our R&D policy based on Ethical, Legal, Social and Economic issues for the mobility system is also introduced.</p>

著者

平石 雅之 蔦原 道久

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 B編 (ISSN:03875016)

巻号頁・発行日

vol.74, no.746, pp.2132-2137, 2008

被引用文献数

2

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We propose the Spectral Lattice Boltzmann Method (SLBM) that is the numerical calculation method of fluids based on the lattice BGK (Bathnagar-Gross-Krook) model discretized with spectral method. Two-dimensional homogeneous isotropic turbulence are simulated by the SLBM. Numerical results agree with another calculation results i.e. the energy spectra proportional to the wave number to -4 and backward cascade of energy is observed. As a result, we obtain the conclusion that homogeneous isotropic turbulence can be simulated by the SLBM, and it is confirmed that this method is useful for numerical simulations of turbulent flows.

著者

村上 碩哉 室田 忠雄 神馬 敬

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会誌

巻号頁・発行日

vol.75, no.641, 1972

著者

堤 一郎 池森 寛 緒方 正則 吉田 敬介

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会九州支部講演論文集 2014.67 (ISSN:24242780)

巻号頁・発行日

pp._612-1_-_612-2_, 2014 (Released:2017-06-19)

著者

木村 友哉 ウラ シャリフ 久保 明彦

出版者

一般社団法人 日本機械学会

雑誌

生産システム部門講演会講演論文集 2021 (ISSN:24243108)

巻号頁・発行日

pp.502, 2021 (Released:2021-09-25)

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本研究では、まず段階的制御されたフラクタル図形を表した点群の周りから特定した面ごとにもう一つの点群を発生。この点群を三角形分割して直接STLデータ及び立体CADモデルを作成する。そのデータは3Dプリンターで簡単にレプリカにすることができる。この結果は複雑な形状のリバースエンジニアリングへの応用が期待できる。

著者

黒岩 源雄

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会誌 (ISSN:24242675)

巻号頁・発行日

vol.84, no.751, pp.534-538, 1981-06-05 (Released:2017-06-21)

著者

徳永 健志 門脇 弘子 森 浩二 齊藤 俊

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.87, no.898, pp.20-00319, 2021 (Released:2021-06-25)

参考文献数

10

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The prevention of an arteriosclerosis, which is a major cause of death in the world has social significance. In previous studies, blood vessel elasticity was estimated by using parameters of blood vessel model. However, the effect of wave propagation on the estimation was ignored. It is not clear how these features affect the estimation of blood vessel elasticity in clinic. In this study, the coupled model of blood vessel and blood flow based on the coupled wave theory was proposed on the assumption that the viscosity is more strongly influenced by blood flow than by blood vessels. Identifying the model parameters of elastic pipes subjected to cyclic pressure fluctuations by using measured pressure and displacement data, we concluded that the coupled model may be applicable for estimating the vessel stiffness in clinical practice.

著者

貞弘 晃宜 道辻 洋平 山北 昌毅

出版者

一般社団法人 日本機械学会

雑誌

ロボティクス・メカトロニクス講演会講演概要集

巻号頁・発行日

vol.2002, 2002

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本論文で考えるアクロバット・ロボットは平面5リンク4アクチュエーターの人間を模した多自由度・多関節のロボットであり, 一端をアクチュエータを持たない自由回転できる鉄棒に固定することにより, 鉄棒の体操選手をモデル化したものとみなせる.このような非ホロノミックシステムに対して, エネルギーと姿勢を同時に目標状態に安定化する周期エネルギー制御により, 着地を行う為に必要な飛出時の並進速度と角運動量を制御する.