著者

田中 伸司 吉冨 雄二

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:18848354)

巻号頁・発行日

vol.78, no.794, pp.3615-3629, 2012 (Released:2012-10-25)

参考文献数

23

被引用文献数

1

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This study aims definition of complex phenomena arising under screw thread fastening process and deep understanding of past relevant knowledge. So far, authors have been studied on screw fastening mechanism of a clamped body with M10 bolt-nut by using 3D elastoplastic FE analysis. In this paper, more precise analytical model is developed and the bolt-nut fastening process is calculated. Consequently, following matters were revealed. (a) Greatly complicated deformation of bolt-nut joined threads area under contacting was clarified qualitatively. Supporting contribution percentages of each thread to axial load was calculated; especially the first thread of joining screw thread supported about 31% of axial force. (b) Spring constant of bolt-nut or clamped part calculated by the present FEM was well accorded with some theoretical equations within 7% error. Contribution of elongation of each region with the bolt also agreed with these equations. Most of all, the validity of Sawa-Maruyama's equation was showed. (c) During fastening process, development of stress or strain at the bolted joint was visualized compatibly alongside of past knowledge and information.

著者

原 進 鈴木 健太 山田 陽滋

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.855, pp.17-00208, 2017 (Released:2017-11-25)

参考文献数

17

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Recently, proceeding of the aging society has encouraged research and development of power assist systems. The authors' research group studies on the assist system control using an assist cart as a rollator. The merit of the proposed system is the aging people walk by themselves using the cart as the assisting tool and it helps anti-aging. Most serious problems of the proposed system are the avoidance of fallings and collisions without losing operability. To solve the problem, this paper proposes the remote control system taking operators' safety and operability into account. The remote control has a possibility of the establishment of the cost-effective multiple target control systems by reducing the requirement for each control target system. However, because of the limitation of communication data capabilities, the controller cannot grasp the state of the controlled object completely. To grasp the state and keep the safety, the authors apply an evaluator in the remote control system. It detects the effect of the uncertainty and keeps the controlled object safe. In addition, as an interface for the users to avoid the collisions, this paper applies the stiffness control. Introducing the virtual spring into the control system, the proposed system prevents the controlled object to collide the obstacle, without losing operability. Based on an application example for the one-dimensional assist rollator collision avoidance, this paper reveals the practicality of the proposed system by conducting experiments and the simulations. The result shows the proposed way is one of the effective ways for applying a remote control system to the assist system problem.

著者

山本 宇紘 小池 卓二 青木 路人 本間 恭二

出版者

一般社団法人 日本機械学会

雑誌

バイオエンジニアリング講演会講演論文集 2008.21 (ISSN:24242829)

巻号頁・発行日

pp.11-12, 2009-01-22 (Released:2017-06-19)

著者

永瀬 和彦 別所 雅章 生田 憲人 漆原 健

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:18848354)

巻号頁・発行日

vol.79, no.806, pp.3432-3441, 2013 (Released:2013-10-25)

参考文献数

3

被引用文献数

2 2

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To keep on-time performance of commuter trains in mega cities, the skillful brake handling is required for the drivers on the approach of the stations. However, on the course of the training for the newly comer drivers, such skill has been telepathically given by their instructors, and none of theories nor quantitative instructions has been introduced. The authors proposed a method to quantitatively evaluate the brake handling skill on the approach of the stations. Using the newly proposed method, they investigated the data piled up in the event recorder of the EMUs operated the JR West Ohsaka Kanjoh Line, one of the most densely train-operated commuter lines in the JRs. On the investigations, they confirmed that the brake handling skill could be easily and quantitatively evaluated by the method. Then, they applied it to investigate the trains operated on the Tohkaido Main Line between Kyoto, Osaka and Kobe, where the interval of the stations is longer and the scheduled operating speed is higher than the formally investigated line. The results of the study are briefly reported in the paper.

著者

伊藤 慎一郎

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 B編 (ISSN:03875016)

巻号頁・発行日

vol.73, no.734, pp.1975-1980, 2007-10-25 (Released:2011-03-03)

参考文献数

7

被引用文献数

2 8

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A slipstream is a region of reduced pressure or even suction (negative pressure) formed behind an object in downstream. Even in a marathon event, it is possible to use preceding runners as a shield to reduce aerodynamic drag and to carry out physical strength presservation. These preceding runners are called pacemakers, who maintain a lap time of an main runner. In this research, to confirm the effect of pacemakers' slipstream and to find a suitable arrangement of pacemakers, drag of the main runner was measured using 3 component load cells in a wind tunnel. And the factor of drag reduction was studied by grasping the flow field using a smoke tunnel. Numerical calculations were also carried out in a real Reynolds number and compared with experiments concerning drag and flow field.

著者

西原 修 坂谷 祐輔 北野 弘明 平岡 敏洋 熊本 博光

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.74, no.738, pp.250-258, 2008-02-25 (Released:2011-08-16)

参考文献数

8

---

The Meihan highway linking Kameyama in Mie Prefecture and Tenri in Nara Prefecture is one of most accident-prone areas in Japan. Representative accident factors that have been identified for the Meihan highway are chronic speeding and complex road alignments, including many sharp curves and steep slopes. One particular section is known as the “Omega curve” as the road shape is similar to the Greek character “Ω”. In this study, the probable effects of proposed plans to improve the road alignment of the Nakahata section are investigated by performing driving simulations to identify typical hazards, ranging from traffic conflicts to vehicle accidents. It was found that incidents that begin as a minor traffic conflicts can frequently escalate to become a fatal accidents. It was also found that improved road alignment generally reduces the required tire forces. For typical traffic conflict patterns reproduced using the driving simulator, it was found that road alignment resulted in considerable improvements in safety indexes which are effective indicators for the occurrence of rear-end collisions.

著者

石綿 良三 根本 光正 山岸 陽一 萩野 直人

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 2013.66 (ISSN:24242780)

巻号頁・発行日

pp.5-6, 2013-03-13 (Released:2017-06-19)

著者

高原 弘樹 新庄 拓也 中野 寛

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会関東支部総会講演会講演論文集 2016.22 (ISSN:24242691)

巻号頁・発行日

pp._OS1105-1_-_OS1105-2_, 2016-03-10 (Released:2017-06-19)

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In recent years, the vibration system which has negative mass characteristics, called meta-material, attracts attention. This system consists of two single-degree-of-freedom system. This two-degree-of-freedom system can be represented to an equivalent single-degree-of-freedom system. In case of the subsystem without a damping, the effective mass of this equivalent system has the negative mass characteristics. When the damping of the system is taken into consideration, the effects of the damping on these negative mass characteristics are not clarified. The effects of damping upon characteristic of vibration system with negative effective mass are investigated. The condition of the negative mass characteristics is derived with a damped subsystem. The effects of the damping of subsystem on the negative mass characteristics are discussed.

著者

神田 康行

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

巻号頁・発行日

vol.85, no.873, pp.19-00035-19-00035, 2019

被引用文献数

1

---

<p>The rigid plastic finite element method (RPFEM) is used in many re-meshing procedures in material processing analysis. Currently, the four-node quadrilateral element, which can avoid volumetric locking, is applied in the RPFEM. However, it is desirable to apply the three-node triangular element instead because of its easy and robust mesh generation procedure. This study applied the three-node triangular element with drilling and strain degrees of freedoms (GNTri3) to the RPFEM, the validity of which was verified by analyzing some numerical examples. First, as verification for the volumetric locking characteristic of the GNTri3, FEM analysis of a nearly incompressible elastic body under plane strain conditions was performed. Volumetric locking was recognized by applying full integration to the element stiffness matrix of the GNTri3. Therefore, it was revealed that the RPFEM using the GNTri3 is necessary for applying selective reduced integration to the element stiffness matrix. Analysis of the RPFEM using the GNTri3 showed that the tool pressure was in good agreement with theoretical solutions and FEM results obtained using a conventional four-node quadrilateral element at a rigid punch indentation. In addition, reasonable material processing deformations were computed in the plane strain compression test.Therefore, validity of the RPFEM using the GNTri3 was verified by numerical results.</p>

著者

中村 優一 角田 直人 山田 幸生

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.2003, pp.65-66, 2003

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Water as well as wastes is removed from the blood of patients under dialysis treatment. If the quantity of the removed water exceeds the limit by some reasons the probability of dangerous accidents becomes high. Therefore, it is highly desired to monitor the blood status continuously during dialysis treatment. This paper presents some results of a fundamental research of measurement of water content in blood using near infrared spectroscopy and multivariate analysis for the purpose of continuous blood monitoring.

著者

影山 拓也 吉田 周平 曽根 宏隆 田中 学 渡辺 隆行

出版者

一般社団法人 日本機械学会

雑誌

熱工学コンファレンス講演論文集

巻号頁・発行日

vol.2016, 2016

---

<p>The purpose of this study is to synthesize lithium transition-metal oxide nanoparticles by induction thermal plasmas. Six different systems of Li-Mn, Li-Cr, Li-Fe, Li-Co, Li-Ti, and Li-Ni were compared to understand the formation mechanism. The obtained results indicated that lithium metal oxide nanoparticles were successfully synthesized in Li-Mn, Li-Cr, Li-Fe, Li-Co, and Li-Ti systems, while those nanoparticles were rarely synthesized in Li-Ni system. This difference was discussed on the basis of thermodynamic consideration. The yield of prepared lithium metal oxides depends on the ratio of Gibbs free energy change of lithium transition-metal oxides to that of metal oxides.</p>

著者

榎本 祐嗣

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:00214728)

巻号頁・発行日

vol.100, no.940, pp.260-261, 1997

著者

神田 康行

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

巻号頁・発行日

2019

被引用文献数

1

---

<p>The rigid plastic finite element method (RPFEM) is used in many re-meshing procedures in material processing analysis. Currently, the four-node quadrilateral element, which can avoid volumetric locking, is applied in the RPFEM. However, it is desirable to apply the three-node triangular element instead because of its easy and robust mesh generation procedure. This study applied the three-node triangular element with drilling and strain degrees of freedoms (GNTri3) to the RPFEM, the validity of which was verified by analyzing some numerical examples. First, as verification for the volumetric locking characteristic of the GNTri3, FEM analysis of a nearly incompressible elastic body under plane strain conditions was performed. Volumetric locking was recognized by applying full integration to the element stiffness matrix of the GNTri3. Therefore, it was revealed that the RPFEM using the GNTri3 is necessary for applying selective reduced integration to the element stiffness matrix. Analysis of the RPFEM using the GNTri3 showed that the tool pressure was in good agreement with theoretical solutions and FEM results obtained using a conventional four-node quadrilateral element at a rigid punch indentation. In addition, reasonable material processing deformations were computed in the plane strain compression test.Therefore, validity of the RPFEM using the GNTri3 was verified by numerical results.</p>

著者

宇宙工学部門 編集部

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.108, no.1034, 2005

著者

丸茂 喜高 清水 勇介 綱島 均 小島 崇

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.80, no.817, pp.TL0278, 2014 (Released:2014-09-25)

参考文献数

11

被引用文献数

1 1

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This study proposes the braking assistance system for train drivers when stopping at a station to prevent the drivers from overrunning and running time delay. The assistance system informs the driver visually of the brake onset position, which is calculated by the assumed deceleration, the present vehicle velocity and the desired stopping position. This study conducts two experiments using the train-driving simulator with three participants. One experiment examines the effects of the driving assistance system on the braking behavior with the mental calculation, which assumes the mental workload. The assistance system makes it possible to decrease the dispersion of the brake onset timing and the running time. The other experiment examines the effects of the brake onset timing on the running time and the safety margin to make the vehicle stop at the desired position. The brake onset timing is adjusted by changing the assumed deceleration. Obtained results show a good correlation between the assumed deceleration and the running time, and the later brake onset timing contributes the shorter running time. In addition, a good correlation between the assumed deceleration and the minimum value of the predicted stopping position, i.e. the safety margin, is also observed, and the later brake onset timing deteriorates the safety margin.

著者

中島 求 江尻 祐介

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.2011, pp._J053014-1-_J053014-5, 2011

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In the previous study, the swimmer mannequin, which reproduces the 3D body shape of an athlete swimmer with high fidelity and can perform three degrees-of-freedom motion, was developed, and the fluid force acting on the swimmer mannequin was measured. In this study, the unsteady fluid force acting on the swimmer mannequin was modeled. The formulation of the swimming human simulation model SWUM, which the authors have already developed, was used for the fluid force model. Three fluid force coefficients in the model were determined using the optimizing calculation so that the discrepancy between the simulated fluid force and experimental one became minimum. Further, the unified coefficients were determined by taking the averages of the values for all the trials. Using the unified determined fluid force coefficients, the comparisons between the simulated fluid forces and the experimental ones were carried out. It was found that the simulation could reproduce the experimental characteristics with respect to the time fluctuation.

著者

石川 君雄

出版者

一般社団法人 日本機械学会

雑誌

東海支部総会講演会講演論文集

巻号頁・発行日

vol.2012, pp._321-1_-_321-2_, 2012

著者

大谷 卓史

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.116, no.1137, pp.593, 2013-08-05 (Released:2017-06-21)

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.121, no.1196, pp.44, 2018-07-05 (Released:2018-09-21)

著者

本田 雅文 牛見 宣博

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.2P1-A13, 2018 (Released:2018-12-25)

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For home robots, functions such as support, dialogue, guidance, and hospitality with human beings are expected while safely moving in coexistence environments of the human being, such as home environments or the like. However, there arise problems concerning hugging on the home robot and falling down of the home robot accompanying it. This paper develops a standing up mechanism during falling down as a wheeled home robot function capable of smooth service.