著者

中越 宏明 澤田 聡 片岡 篤史

出版者

一般社団法人 日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2012, pp._445-1_-_445-8_, 2012

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In order to measure the vibration characteristic of a product, the experiment modal analysis is used well. However, in the method of moving a measuring point, sensor weight affects the frequency response function (FRF) to measure. Therefore, by the conventional method, it was not in agreement by the place which natural frequency measures, and there was a problem that it was difficult to extract mode shape correctly. In this paper, we propose the method of eliminate the influence of sensor mass from the measured FRF for the experiment modal analysis of light weight products, and extracting more exact mode shape. Improvement in a MAC value has been checked because it is adapted in the proposed method. So, the usefulness of the proposed method was shown.

著者

章 忠 井 和章 三宅 哲夫 今村 孝 堀畑 聡

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.739, pp.642-649, 2008-03-25 (Released:2011-03-04)

参考文献数

10

被引用文献数

1 1

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The direction of a generated sound source can be estimated by humans using the time difference between both ears and the characteristics of the sound. However, it is very difficult to create an estimation system using a computer and two microphones. Aims of this study are the achievement of three dimension sound localization with two microphones. We have developed the sound source direction estimation system, in which the sound source direction can be shown by two angles, the horizontal angle α and the vertical angle, β. The former is presumed from the difference of the arrival time when the sound progresses from the source to right and left ear, and the latter is presumed from spectrum correlation analysis using head related transfer function (HRTF). In this study, we propose a novel sound source direction estimation method, in which the feature difference of two recorded microphone signals is used. As a result, an average correct estimation rate of 96% was obtained in determining the location of 11 kinds of object sounds.

著者

釘田 慎也 馬渡 俊文 中島 晃

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.2006, pp.289-290, 2006

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Using a two-roller testing machine, the authors examined the surface durability of thermally sprayed WC-Cr-Ni cermet coating under unlubricated condition. By means of the high energy type flame spraying (Hi-HVOF) method, the coating of about 110μm in thickness was formed onto the axially ground, blasted and circumferentially ground roller specimens made of a thermally refined carbon steel or a carburized and hardened steel. The WC cermet coated roller finished to a mirror-like condition with a roughness of 0.1μmRz was mated with the carburized and hardened steel roller without coating ground to a roughness of 0.1μm〜8μmRz, and a maximum Hertzian stress of P_H=1.2GPa was applied in line contact. In the case of the thermally refined steel substrate, the life to flaking became short independent of the substrate surface finish. On the other hand, the carburized hardened steel substrate roller showed a higher durability. The effect of substrate material on the durability of thermally sprayed coating was discussed by the elastic-plastic analysis of the subsurface layer.

著者

中島 晃 馬渡 俊文 MAWATARI Toshifumi 吉田 一

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

巻号頁・発行日

vol.2004, pp.349-350, 2004

著者

山下 誠一郎 樫村 幸辰

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

巻号頁・発行日

vol.2011, pp.125-126, 2011

著者

佐野 紘平

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

巻号頁・発行日

vol.2007, pp.539-540, 2007

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交通事故死者数の半減が日本の国家目標になっている。技術史上の大発明であるシートベルトと車体構造の進化により、交通事故による24時間以内死亡者数は減少しているが重傷者数は増加しており、交通弱者である子供(15歳以下)ならびに高齢者の死亡・重傷者合計数が増加している。死者・重傷者の半減に貢献するために、最適化設計されたシートベルトと故池田正彦氏が発明した衝撃緩衝装置を組み合わせて、乗員保護効果を極大化することを提案する。さらに、高齢者の認知・反応機能劣化に対応して、RFID装置を歩行者・自転車乗用者認識用のエージェント指向通信・放送システムとして適用することを提案する。

著者

逢坂 一正 藤本 真作 小野 敏郎

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C編 (ISSN:03875024)

巻号頁・発行日

vol.58, no.552, pp.2489-2494, 1992

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Optimal reference trajectories for n-link robot manipulators are planned. They are generated from the performance indices which are the integral of the square of acceleration, jerk, and so on of the trajectory with respect to the control time. The optimal reference trajectories are compared through an experiment in high-speed motion control of a 2-link robot manipulator, and a good control performance is obtained in the case of higher continuity of the trajectory.

著者

吉田 倫幸

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.98, no.918, pp.403-406, 1995-05-05 (Released:2017-06-21)

被引用文献数

1

著者

佐藤 浩

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.63, no.497, 1960

著者

五味 健二 新津 靖

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.82, no.838, pp.15-00498, 2016 (Released:2016-06-25)

参考文献数

37

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Understanding stress or strain distribution or birefringence properties is important for proper industrial application of polymer films. For example, it is very important to control the stress and birefringence distribution in polymer films that are used for liquid crystal displays of PCs or smart phones, etc. for their performance improvement. As another example, it is very important to understand the stress distribution in packaging polymer films for reliability management of the package because the forming accuracy depends on the stress distribution in the films. Photoelastic analysis is suitable to understand stress, strain distribution and birefringence properties on polymer films; however, understanding of the stress-optical or strain-optical coefficients of the polymer is indispensable when using the analyzing method. In this study, the influence of displacement rate, stress orientation and stress history on birefringence properties is measured for polyvinylidene chloride (PVDC) at room temperature as an example of semi-crystalline polymer films. The stress-optical coefficient of PVDC depends on the displacement rate, stress orientation and stress history. On the other hand, the strain-optical coefficient of PVDC is approximately independent of them. These phenomena are explained by the result from the viscosity, polymer chain orientation and strain-induced crystallization in PVDC. There is potential given that strain-optical coefficients for semi-crystalline rubbery polymers are approximately independent of the displacement rate, stress orientation and stress history on some conditions because of the mechanism of the phenomenon.

著者

高田 稜一 高橋 江梨香 内田 孝紀 杉谷 賢一郎 谷川 博哉 野口 尚史 平田 勝哉

出版者

一般社団法人 日本機械学会

雑誌

流体工学部門講演会講演論文集 (ISSN:24242896)

巻号頁・発行日

pp.OS03-05, 2020 (Released:2021-05-25)

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In the present study we investigate the relationship between various aerodynamic characteristics and attack angle α for FP (a flat plate), NACA0015 and iNACA0015 (the NACA0015 placed back to front) by numerical analysis and water-tank experiment at Re = 100 – 800. Then, we reveal the effects of α upon various aerodynamic characteristics such as the lift coefficient CL, drag coefficient CD and the lift-to-drag ratio CL/CD. In order to discuss these revealed α effects, we further visualize the flow around the airfoils in terms of the velocity vector, vorticity and the Q value at α = 0 – 30 deg., based on PIV analyses by water-tank experiment. Such results suggest that FP is similar not with NACA0015 but with iNACA0015 from an aerodynamic point of view.

著者

岡屋 達也 小河原 加久治 新銀 秀徳 野本 正晃

出版者

一般社団法人 日本機械学会

雑誌

年次大会 2018 (ISSN:24242667)

巻号頁・発行日

pp.S0520305, 2018 (Released:2019-03-25)

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This paper studies the separation flow reduction effect around NACA0015 airfoil using PSJA. We expect to reduce fluctuations of wake velocity by PWM control input applied to PSJA using DFC. This paper shows change of the lift force by the DFC in 5m/s main flow velocity and 15deg angle of attack. We attempted two modes by setting 4msec delay time of DFC. DFC positive mode set to ON the PWM signal when the input exceeds the threshold. DFC reverse mode set to ON the PWM signal when the input falls below the threshold. The experimental results show that the DFC result with a delay time of 4ms recovers lift force compared to without control of PSJA. In the both modes 4msec delay time, lift force is maintained without depending on the threshold at 1 second driving start. At the threshold 0.01 of the reverse mode, lift force is kept than the other threshold.

著者

張 学超 森 敬祐 真壁 朝敏 安藤 新二 井上 晋一

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

巻号頁・発行日

vol.2021, 2021

著者

真壁 朝敏 S. M. Moshiar RAHAMAN 名嘉 海人 真鍋 光輝

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

巻号頁・発行日

vol.2021, 2021

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.111, no.1070, 2008

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.111, no.1070, 2008

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.111, no.1070, 2008

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.111, no.1070, 2008

著者

南海 昂輝 鈴木 健人 小室 淳史 野々村 拓 浅井 圭介

出版者

一般社団法人 日本機械学会

雑誌

年次大会 2019 (ISSN:24242667)

巻号頁・発行日

pp.S05212, 2019 (Released:2020-03-25)

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A linear reduced-order model of flow fields around an airfoil controlled by a plasma actuator is constructed based on experimental data. An alternating-current dielectric-barrier-discharge plasma actuator (ac-DBDPA) with random input was used to control flow fields around a NACA0015 airfoil at the chord Reynolds number of 6.4 × 104 in a wind tunnel testing and time-resolved data of the velocity fields were obtained by particle image velocimetry. Proper orthogonal decomposition (POD) was employed to the data and the lower-dimensional description of them was obtained by using the first ten POD modes. Subsequently, the least-squares method was applied to the time history of the POD modes and the control input corresponding to the voltage amplitude of ac-DBDPA, and the coefficient matrix of the linear model was computed. The effects of the control input on the velocity fields reconstructed by the POD modes were investigated from the input matrix. It is shown that the velocity fields are not influenced much when the average value of the input is changed. On the other hand, they are sensitive to the input change. This result corresponds to the fact that the intermittent actuation is effective for the flow control by plasma actuators such as the burst-mode actuation or nanosecond-pulse-driven DBDPA.

著者

原田 大輔 榊原 潤

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 2017.23 (ISSN:24242691)

巻号頁・発行日

pp.201, 2017 (Released:2017-06-19)