著者

原田 康平 真木 康隆 石栗 航太郎 奥村 正弘 古賀 進一郎

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 2018.27 (ISSN:24243175)

巻号頁・発行日

pp.2103, 2018 (Released:2019-06-25)

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The train positioning system by means of the ATS beacon used in the pendulum car requires sorting out the ATS beacon and updating the in-vehicle database according to the relocation of ATS beacons. Under the method proposed, track curvature data calculated by means of dividing the yaw rate of the carbody by the running speed are held as the on-board database, and the position of the train is detected based on the comparison with the track curvature data during running. In this case, applying a spatial filter improves detection accuracy and reduces database updating frequency. This paper presents the outline of the system and the detection accuracy.

著者

羽島 金三郎

出版者

一般社団法人 日本機械学会

雑誌

機械學會誌 (ISSN:24331546)

巻号頁・発行日

vol.30, no.118, pp.75-104, 1927-02-20 (Released:2017-08-01)

著者

清 水

出版者

一般社団法人 日本機械学会

雑誌

機械學會誌 (ISSN:24331546)

巻号頁・発行日

vol.35, no.177, pp.77-79, 1932-01-01 (Released:2017-08-01)

著者

吉田 皓太郎 若松 栄史 岩田 剛治 久保 貴裕

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.903, pp.21-00201, 2021 (Released:2021-11-25)

参考文献数

12

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A method to design the function of the brassiere cup shape as developable surfaces and its developed shape using Gaussian Process Regression is proposed. A developable surface, which is generated by sweeping a straight line along a three-dimensional curve, can be seen many products such as ships, buildings, clothes, and so on. The shape has not only its aim which can be formulated but also that which cannot be formulated such aesthetics. In this paper, we focus on a brassiere cup. A brassiere cup is composed of several patterns and the cup shape is designed by repeatedly making paper cup model and then checking its three-dimensional shape. For improvement of design efficiency of brassieres, such trial and error must be reduced. The difficulty of the design process is caused by the function of a brassiere cup. Its function, such as to enhance woman’s breast size, et.al., is difficult to formulate and unclearly correlated with its three-dimensional cup shape. In this paper, we propose a method to support the design of the three-dimensional shape of a cup and its developed shape by machine learning when the cup shape and quantitatively evaluated value of its function are given as a set of data. First, we formulate the cup shape as developable surface using differential geometry. Then, we propose the method to extract the attribute from the three-dimensional cup shape based on the differential geometry and a predictor of an output value for its attribute using Gaussian Process Regression. The validity of the method is confirmed by a numerical experiment regarding the evaluated value using its volume and size. Finally, we propose a method to design the cup shape using this predictor. We experimented whether our proposed method can output the approximate cup shape when the evaluated value of the cup is given.

著者

松井 信夫

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.71, no.594, pp.984-990, 1968-07-05 (Released:2017-06-21)

著者

竹下 英之 榎本 和城

出版者

一般社団法人 日本機械学会

雑誌

年次大会 2011 (ISSN:24242667)

巻号頁・発行日

pp._G040021-1-_G040021-3, 2011-09-11 (Released:2017-06-19)

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Recently, from the viewpoint that decreases the load to the global environment, the bio-plastics, which are derived from the reusable resources from the biomass, attract much attention as new polymeric materials instead of the polymers derived from exhaustible resources such as petroleum. Poly lactic acid (PLA) is considered to be one of the most promising bio-plastics because its strength and modulus are as high as that of the existing plastic, and it has also biodegradability. In this study, we investigated the effect of immersion in gasoline on mechanical properties of injection-molded PLA plates in the case of assuming that PLA will be applied to severe environment such as in contact with gasoline.

著者

原島 博

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.105, no.1009, pp.784-785, 2002-12-05 (Released:2017-06-21)

著者

横堀 章一

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.47, no.323, pp.81-82, 1944-04-01 (Released:2017-06-21)

著者

福川 秀夫

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.46, no.310, pp.54-58, 1943-01-01 (Released:2017-06-21)

著者

原 乙未生

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.46, no.318, pp.619-620, 1943-09-30 (Released:2017-06-21)

著者

原 乙未生

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.45, no.304, pp.448-450, 1942-07-01 (Released:2017-06-21)

著者

北村 洋三 谷川 清 福川 秀夫 上西 甚藏 瀧山 敏夫 小林 正一郎 北畠 顯正 田島 達之輔 原 乙未生 間瀬 徳造 縣 敏 奧 礎一 竹村 勘〓

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.41, no.258, pp.839-855, 1938-09-01 (Released:2017-06-21)

著者

松平 精

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.75, no.646, pp.1556-1564, 1972

著者

岡田 昌史 岡本 裕 舛屋 賢

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.86, no.884, pp.19-00320, 2020 (Released:2020-04-25)

参考文献数

14

被引用文献数

2

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For robotic teleoperation, semi-autonomous control, i.e. autonomous control allowing human interposition will be an effective way overcoming delay of electrical communication and emergency operation. We have proposed semi-autonomous control method focusing on excavation in teleoperation environments. In the method, a model of human operation is designed and human internal state is estimated by Extended Kalman Filter. In this paper, experimental evaluations are conducted and reported about ”Digging” process. A human skill of excavation is modeled by an attractor-based dynamics embedding shallow and deep digging trajectories for soft and hard soil, respectively. An index parameter is changed based on the load of the bucket, and a seamless motion transition is realized satisfying the restriction by setting a threshold. Moreover, by adding a human operation to the autonomy, the proposed method will cope with the emergency, which is experimentally evaluated.

著者

大場 啓介 長嶺 拓夫 森 博輝 佐藤 勇一

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 (ISSN:21879761)

巻号頁・発行日

vol.81, no.824, pp.14-00593, 2015 (Released:2015-04-25)

参考文献数

8

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This paper describes the investigations of the characteristic about the sound generation of a nose flute experimentally. The nose flute is attached to the upper part of a container. If air is passed to a nose flute, sound will occur. The volume of a container is changed and the generated sound is measured. The natural frequencies of an experimental device are calculated and we confirm that it is in agreement with frequency of sound generated in experiment. We show that nose flute is a unique musical instrument with the point that a nose flute has only an edge part and uses people's mouth for a resonance body part. The frequencies of resonance sound can be calculated from the capacity in a mouth, the thickness and the area of an opening of a nose flute. When people play a nose flute, it is thought that only the first mode of vibration is used.

著者

松永 拓也 越塚 誠一

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 (ISSN:21879761)

巻号頁・発行日

vol.87, no.895, pp.20-00437, 2021 (Released:2021-03-25)

参考文献数

14

被引用文献数

2

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This study concerns the computational accuracy of a particle method for a time-dependent incompressible flow. In recent years, accurate spatial discretization schemes have been developed for a particle method. However, the actual convergence rate in space tends to be much lower than the order of the leading truncation error given by an adopted spatial discretization scheme. This suggests that the Δt-dependent error is comparably significant with respect to the truncation error of the spatial discretization scheme. Under these circumstances, we have developed a new time marching method to improve the computational accuracy by reducing the Δt-dependent error and improving the convergence property. The proposed time marching method is based on the 1st-order fractional step method, just as the conventional methods. However, as opposed to the past studies, the convection term is explicitly included in the provisional velocity calculation, as an Eulerian-based approach. By doing this, the Δt-dependent error caused by the particle movement can be avoided. A numerical test has been carried out using the two-dimensional Taylor-Green vortex problem, where 2nd- and 4th-order spatial discretization schemes are adopted. As a result, the conventional time marching methods gave much lower convergence rate than the order of the spatial discretization scheme. On the other hand, the proposed time marching method showed approximately 2nd- and 4th-order convergence in space with the 2nd- and 4th-order spatial discretization schemes, respectively. Therefore, the proposed method is indicated to highly improve the computational accuracy.

著者

岡田 昌史 岡本 裕

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

pp.19-00167, (Released:2020-03-25)

参考文献数

7

被引用文献数

1

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In general, mechanical systems are stabilized on their equilibrium point. Equilibrium point is often not unique and they are continuously connected, which is an equilibrium manifold. To stabilize the mechanical system on an equilibrium manifold will enable optimal control including the selection of the stabilizing position. In this paper, we propose a controller design method that stabilizes a mechanical system on an equilibrium manifold based on vector field. The equilibrium manifold is derived from dynamic equations, and by setting an appropriate evaluation function, (1) an optimal equilibrium point from arbitrary initial value is calculated, (2) a trajectory, input and vector field are derived based on linear control theory, (3) a controller is designed using functional approximation. Simulations show that different initial values are stabilized to different equilibrium points, and experimental results show the effectiveness of the proposed method.

著者

横井 嘉文 平尾 恵子

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:18848346)

巻号頁・発行日

vol.77, no.775, pp.590-601, 2011 (Released:2011-03-25)

参考文献数

10

被引用文献数

2 2

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In this study, the flow features of vortex shedding from a pair of parallel arranged circular cylinders (same diameters and unequal diameters) oscillating along the direction of the flow were observed by visualizing water flow experiment at the ranges of the frequency ratio f/fK=0-7, amplitude ratio 2a/d=0.125, 0.25, 0.5 and 0.75, gap ratio G/d=0.25, 0.75 and 1.75, and Reynolds numbers Re=470-670. The variations of mean vortex shedding frequency from each oscillating cylinder were investigated. As a result of the experiments, typical flow patterns of lock-in or un-lock-in state were shown every gap ratio G/d. It was found that the stage number of flow pattern was depended on the gap ratio G/d. In the cases of gap ratio G/d=0.25, there were four states, in the case of gap ratio G/d=0.75, there were six states, and in the case of gap ratio G/d=1.75, there were seven states. It was found that the measurement result of vortex shedding frequency depended on the observation point because the rearrangement of vortex formation had changed the characteristics of the flow. When the cylinders were oscillated to the direction of flow, the flow pattern of bias gap flow became not seen. The map of lock-in state in the lock-in range was obtained. It was found that the lock-in range and the lock-in form were more different from the case of single oscillating cylinder.

著者

高橋 諒太 木下 貴博 酒井 拓見

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

巻号頁・発行日

vol.2020, 2020

著者

菊地 謙次 今野 友博 市川 誠司 窪田 佳寛 望月 修

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:18848346)

巻号頁・発行日

vol.79, no.798, pp.151-163, 2013 (Released:2013-02-25)

参考文献数

29

被引用文献数

2

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The purpose of this study is to know differences between steady and unsteady drag coefficients of a sphere. Though we often have to estimate unsteady drag-forces acting on a moving obstacle, we are obliged to use the well-known steady drag coefficient for the first estimation because of lack of information about effects of unsteadiness on the drag coefficient. The usual way to take account of unsteadiness is an added mass. However, its application is restricted within the simple shape of an obstacle. We propose a way based on the equation of motion to obtain the unsteady drag coefficient. To confirm validity of the way, we measured and analyzed the motion of the falling sphere in water by using a high-speed camera and a motion capture method. The drag coefficients as a function of time were obtained by substituting measured values of velocity and acceleration into the equation of motion. The drag coefficient was 0.52 when the sphere attains the terminal velocity, being quite large at the beginning of motion. Comparing with the values obtained by the other previous studies, our result is reasonable.