著者

廣明 慶一 河合 伸人 渡辺 昌宏

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.852, pp.17-00025-17-00025, 2017 (Released:2017-08-25)

参考文献数

20

被引用文献数

2

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This paper presents a three dimensional flutter analysis of slender webs under tension in cross flow. In the flutter analysis, Doublet-point method based on the unsteady lifting surface theory is used to calculate unsteady fluid force acting on the web surface. The equation of motion of the web under tension is derived by using the finite element method. Flutter velocity, frequency and mode are predicted through the root locus of the flutter determinant of the system with changing flow velocity. The theoretical results are compared to experimental results to confirm validity. Moreover, the local work done by the fluid force acting on the web surface is calculated, and instability mechanism is discussed. Lastly, unified empirical equation of flutter velocities for several parameters of webs is proposed.

著者

山本 真 山本 忠 西山 修二

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.852, pp.17-00006-17-00006, 2017 (Released:2017-08-25)

参考文献数

26

被引用文献数

2

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This paper presents theoretical research on an optimum transition curve with smoothly changing curvature using a multiple clothoid curve for improving the occupant ride comfort of automobiles. At the connecting points between an inlet straight line and a circular arc, or between a circular arc and an outlet straight line, vehicles cannot run smoothly owing to the discontinuity of curvature. Especially, the vehicles equipped with a driving support device which assists driver's steering operation or performs steering operation instead of a driver will increase both unstable movement of vehicle and discomforts of occupant. Moreover, the discontinuity of curvature in the connecting points makes the control of advanced accuracy of apparatus difficult. In order to solve such problems, three dimensional vehicle occupant model which is 21 degrees of freedom is assembled, and the multiple clothoid curve is proposed as a new transition curve. The validity of the multiple clothoid curve is shown as compared with the case where it is interpolated by a single clothoid curve or by a non-interpolation. It was found that the influence of the multiple clothoid curve on vehicle movement and ride comfort is superior to those of the single clothoid curve or the non-interpolation. Some results are presented in the form of parametric plots.

著者

佐藤 航

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.801, pp.1027-1037, 2013 (Released:2013-05-25)

参考文献数

18

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I describe our study on a cooling device that is based on the electrocaloric effect (ECE). The ECE causes increases and decreases in the temperature of a dielectric material by changing the electric field. I used a multi layer ceramic capacitor (MLC) to demonstrate the temperature change based on the ECE. The temperature change of commercial MLCs can be controlled by applying a voltage to them and the maximum change is 0.55 K when using 300 V. However, these changes occurred sequentially by applying and removing the voltage. Therefore, it was difficult to apply this phenomenon to a cooling device. I used a heat pipe that had an anisotropic heat conduction feature in this study to separate the heating and cooling. I developed a cooling device consisting of MLCs and a heat pipe containing acetone as the working fluid. The MLCs were set in the bottom of the heat pipe as the cold side and the other side of the heat pipe was attached to a heat sink as the hot side. Only the heat of the ECE in this device was transferred to the heat sink. The temperature of the cold side decreased by applying and removing the voltage periodically. This device demonstrated that the temperature of an MLC dropped 0.49 K when using 300 V at 0.10 Hz frequency.

著者

立畠 健一 植田 好雄 劉 棟博 藤井 文武

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.852, pp.16-00462-16-00462, 2017 (Released:2017-08-25)

参考文献数

15

被引用文献数

1

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This paper discloses the development of the improved Bouc-Wen model which captures the behavior of the rate dependent hysteresis of a piezoelectric actuator. The basic form of the Bouc-Wen model only exhibits symmetric hysteresis loop for a sinusoidal input with no DC offset, whereas the real world bi-morph type actuator occasionally exhibits asymmetric loop for the same stimuli. The present works also proposes the integration of the FIR filter to the model to capture phase lag caused by the structural oscillation of the actuator. Comparison of the modeling accuracy has been given with our recent work of adaptive Preisach model. The result shows that accuracy of the two models are almost the same but the intrinsic difference lies in the number of parameters to be determined to form a computable model: the proposed model has only 25 parameters whereas the adaptive Preisach model includes 5050 discretized distribution function values to establish a single model.

著者

末永 陽介 柳岡 英樹 菊池 護 佐々木 駿

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.852, pp.17-00160-17-00160, 2017 (Released:2017-08-25)

参考文献数

19

被引用文献数

1

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Experimental study was performed to reveal the response characteristics of a stretched cylindrical diffusion flame to sinusoidal oscillation of air flow velocity. The cylindrical flame used in this study has a convex curvature with respect to air stream and is formed in air stream. The fuel is methane, diluted with nitrogen, and the oxidizer is air. Oscillation frequency f is varied from 5 Hz to 250 Hz. Velocity at the outlet of air supplying nozzle was changed sinusoidally with four speakers. Velocity at the fuel nozzle outlet was kept constant. The air velocity at the nozzle outlet is measured using particle image velocimetry. Flame radius rf, flame thickness δ, and flame luminosity Lf are obtained by using high speed video camera. Results are summarized as follows: Though fluctuation amplitude of the velocity gradient of air stream Δga is constant with increasing f, that of the fuel stream Δgf increases. The fluctuation amplitude of rf varies to quasi-steady at low frequency, while the fluctuation amplitude is reduced with increasing f. Lf does not respond to quasi-steady at low frequency. The fluctuation amplitude of Lf has maximum value at 50 Hz and is larger than that for the steady flame corresponding to the velocity fluctuation. It is considered that this complex change of the flame luminosity with respect to f is related to δ/rf which is associated with the flame curvature effect, ga which affects the flame stretch effect, and gf which impacts fuel transport.

著者

竹内 誠一 岡本 達幸

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.852, pp.17-00041-17-00041, 2017 (Released:2017-08-25)

参考文献数

29

被引用文献数

2

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Theoretical examinations based on absorption line databases were carried out about the influence of turbulence-radiation interaction on the radiative heat transfer arriving at the wall of large-scale industrial furnaces, where the re-absorption of radiative energy by combustion gas on its path toward objects to be heated cannot be neglected. In this study, the efficient and accurate calculation method for non-gray analysis and the effective method for handling turbulent fluctuations of radiation and absorption proposed in our previous paper were coupled. Combining the above coupled method and a governing equation solver for obtaining the spatial distribution of time-averaged values of temperature, concentration, velocity and so on, the heat transfer including radiation in large-scale industrial furnaces enveloping turbulent flames was able to be evaluated with sufficient accuracy equivalent to Line-by-Line analysis and with feasible calculation load. By applying this calculation technique to large-scale furnaces, it was found that negligence of turbulent fluctuation in numerical simulation gives rise to obvious change in heat flux distribution on the side wall and in the spatial distribution of time averaged temperature. In addition, change in the total amount of radiative energy arriving at side wall caused by negligence of turbulent fluctuations is fairly small compared with change observed in the case of a typical optical path indicated in our previous report.

著者

前田 慎市 及川 陽介 星野 隆介 小原 哲郎

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 (ISSN:21879761)

巻号頁・発行日

vol.83, no.852, pp.17-00039-17-00039, 2017 (Released:2017-08-25)

参考文献数

10

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A detonation wave propagating in a straight tube (detonation tube) was reflected off the end wall of the tube, and the pressure profile produced by the propagation of the reflected shock wave was experimentally investigated. The detonation wave was initiated at the opposite end of the reflection end, and two ignition conditions were tested. First, ignition at the closed end of the tube (called as “closed ignition end condition”), where the fluid motion was negligible, was evaluated. Second, ignition at the open end of the tube (called as “opened ignition end condition”), where the burned gas flowed toward the vacuum tank attached to the detonation tube, was evaluated. Karnesky et al. (2013) suggested the empirical model in order to represent the pressure profile near the reflection end in the closed ignition end condition. In this paper, the empirical model of Karnesky et al. was modified in order to represent the pressure profile in the opened ignition end condition, and the effect of two ignition conditions on the pressure profiles was discussed. In these models, the pressure profile at the reflection end was empirically formulated by using two empirical parameters, and a uniform pressure distribution between the reflected shock wave and the reflection end was assumed. In this paper, the empirical parameters were normalized by the characteristic parameters for the propagating reflected shock wave. These parameters expressed the conditions of the combustible mixture and the length of the detonation tube. In the opened ignition end condition, the model well represented the measured pressure profile created by the propagating detonation wave and reflected shock wave in the entire length of the detonation tube because the rarefaction wave existed in the entire region behind the detonation wave, and the pressure behind the reflected shock wave had an approximately uniform distribution. Conversely, the model was applicable for a limited duration for the closed ignition end condition because a pressure gradient gradually developed behind the reflected shock wave when the reflected shock wave began to propagate in the plateau region behind the rarefaction wave.

著者

楠山 純平 本多 歩 岩橋 伸太郎 北嶋 孝之 由井 明紀 伊東 利洋 Lu X. Slocum A. H.

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.852, pp.17-00102-17-00102, 2017 (Released:2017-08-25)

参考文献数

23

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Si wafer diameter tends to be increased from 300 mm to 450 mm in order to increase semiconductor device productivity. To this end, the authors developed a rotary grinding machine with high stiffness, equipped with water hydrostatic bearings. This grinding spindle is designed to govern infeed motion of the grinding wheel. This study investigates the basic design and performance of the grinding spindle system. This system itself is composed of a constant pressure water hydrostatic bearing as a radial bearing and a magnetic actuator as a thrust bearing. The magnetic actuator combine the infeed device and the thrust bearing. The measured results show that the static stiffness, Ks, is 1.06 kN/μm, the natural frequency is 353 Hz, and the positioning accuracy is 0.2 μm. These results meet the performance requirements necessary to grind φ450 mm Si wafer.

著者

滝 康嘉

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 2008.5 (ISSN:24331325)

巻号頁・発行日

pp.179-180, 2008-08-02 (Released:2017-08-01)

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In this paper, the student's interests to the mini-4WD are described. This interest is based on the comic and cartoon, and these technologies can be realized by recently ITS. In the college PBL, students were trying to mini-4WD like ITS. And future plan are described.

著者

黒田 雅利 釜谷 昌幸 山田 輝明 秋田 貢一

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.83, no.852, pp.17-00072-17-00072, 2017 (Released:2017-08-25)

参考文献数

13

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In order to assess the fatigue damage of austenitic stainless steels by electron backscatter diffraction (EBSD) method more simply and easily, it should be more preferable to use a commercially available general-purpose EBSD analysis software rather than to employ an in-house developed EBSD analysis programme. In the present study, EBSD measurement was performed for Type 316 austenitic stainless steels subjected to cyclic loading, and the applicability of the EBSD parameter relevant to the pattern quality, which could be obtained by the commercial software, to the fatigue damage assessment was discussed by comparing the other EBSD parameter of the averaged local misorientation (Mave), which could be calculated by the in-house developed programme. As a result, the EBSD parameter relevant to the pattern quality, which signified the full width at half maximum (FWHM) of the histogram distribution of the image quality (IQ), was saturated at the beginning stage of the fatigue cycles, while Mave was increased monotonically with the cycles. This suggested that the FWHM of IQ could be useful to detect the initial stage of the fatigue damage, while Mave was suitable for the quantitative evaluation of the fatigue damage. XRD measurement was also carried out for the same samples employed in the EBSD measurement, and the XRD data was compared with the EBSD data to discuss the crystallographic mechanism of the change in the FWHM of IQ. As a result, it was found that the FWHM of the (111) XRD peak correlated well with the FWHM of IQ. Because the (111) plane in fcc metal such as austenitic stainless steel was most preferable for slip system, this implied that the change in the distribution of the pattern quality generated by the fatigue loading could be due to the slip deformation.

著者

真鍋 健一 小林 直矢 尾崎 純一 筒井 喜平

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.852, pp.16-00586-16-00586, 2017 (Released:2017-08-25)

参考文献数

24

被引用文献数

1

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A new finite element model of textile green composites is proposed to simulate thermoforming process in this study. The model is assembled with actual configuration of the green composites and the interface between yarn and matrix has certain GAP. The mechanical behavior of yarn was considered by using truss element. To verify these models, deep drawing tests were performed with experiment. As a result, orientation of yarn and thickness of drawn cup agreed with experiment well. After this process, strength of drawn cup was evaluated with compression test in both finite element method (FEM) and experiment. In FEM, to remove GAP between yarn and matrix, tied contact method that adjust the unconformity of mesh was used. The deformation behavior of the drawn cup agreed with experiment. The effectiveness of thermoforming process to design products with FEM was verified.

著者

野間口 大 中切 拓 藤田 喜久雄

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.17-00122, (Released:2017-09-19)

参考文献数

22

被引用文献数

4

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Generation of new concepts in product design process serves as driving force of innovation. While many methods have been proposed for supporting design concept generation, it has rarely been supported in a systematic way, because its process is done in designer's implicit thought, and therefore, it is difficult to explicitly formalize the process. This paper proposes a model of designers' thinking process in concept generation called ECF cycle. It consists of three steps, i.e., (1) Externalization: the step for representing design concepts with drawings and language, (2) Classification: the step for classifying concepts with function trees, and (3) Finding voids: the step for finding potentials of new concepts called void, which is a defect of the classification. Then, this research builds a new method of concept generation incorporating the theory of solving inventive problems (TRIZ). The method is based on a quick reference table of TRIZ principles, which helps designers to create a new concept corresponding to a void found by ECF cycle. A case study of concept generation of new running shoes is demonstrated in order to verify the ability of the proposed method.

著者

松岡 信一

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 C編 (ISSN:03875024)

巻号頁・発行日

vol.55, no.517, pp.2481-2486, 1989-09-25 (Released:2008-02-21)

参考文献数

8

被引用文献数

4 5

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This paper give a description of an experimental study of ultrasonic welding of ceramics and aluminium or copper. The ultrasonic welding technique can be carried out in many different ways, such as in direct welding of ceramics and metals, the coating of metal on ceramics surface by vacuum deposition, and in application of inserting of activated metals. The ultrasonic welding has made possible to weld various ceramics, such as SiO2, Al2O3, SrO, BaO, ZrO2, Si3N4, SiC, to aluminium or copper under the room temperature quickly and easily compared to other welding methods. For example, the ultrasonic welding of Al2O3 and aluminium could be finished under the condition of amplitude 23μm of ultrasonic horn top, welding pressure 20 MPa, required duration 0.3 s. The clean with a forced ultrasonic vibration of contact surface needs no surface treatment. Moreover, the material can be processed easily, and it gives out little heat, and hardly get weakness.

著者

武藤 一夫 市川 二朗 大泉 敏郎 中島 宣洋

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.67, no.663, pp.3650-3655, 2001-11-25 (Released:2008-02-26)

参考文献数

5

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In this paper we describe the effect of die-sinking EDM under mirror finishing conditions on mirror surface properties of four-different types steel, SKD11, NAK55, PX5 and SKD61, which contain the free cutting element, sulfur. In particular, the influences of the quantity of sulfur on the machined steel surface, the composition and microstructure with die-sinking EDM. The following conclusions were obtained. 1) A mirror surface of steel containing more than 0.04% sulfur could not be realized. 2) In the case of steel with 0.1% sulfur, the surface property is dependent on the machining direction. 3) Pits are generated on the machined steel surface because the aggregated part of the MnS fiber preferentially melts with the circumferential base metal. In addition, the quantity and shape of pits change according to those of MnS. In the longitudinal section, the shape of the pit is a series of channels, whereas in the transverse section it is a cirele.

著者

齊藤 由貴 白鳥 敏正

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.2010, pp.301-302, 2010

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An experiment has been conducted to investigate static pressure fluctuation behind shock wave in self-excited shock wave oscillation phenomenon on 2D symmetrical circular-arc airfoil in internal transonic flow. Static pressure fluctuation was measured by high-response static pressure probe, and flow was visualized by Schlieren method. Experimental results show that static pressure fluctuation become smaller, as shock wave movement become smaller. In addition, concerning the phase delay of static pressure fluctuation behind shock wave, the overall trend is that the phase delay becomes larger, as the measured point leave for shock wave. When the shock wave form is saw tooth wave, phase delay trended to different from when the shock wave form is sine wave.

著者

長井 健一郎 生沼 秀司 石井 達哉

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.2010, pp.171-172, 2010

被引用文献数

3

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世界的な環境問題への関心の高まりと、今後見込まれる航空輸送量の増加より、航空機の騒音規制はますます厳しくなるものと予想される。航空機騒音の主な要因はエンジンからの騒音であるが、近年ではターボファンエンジンの高バイパス比化により低騒音化が進み、相対的に高揚力装置や離着陸装置など機体から発生する騒音が顕著になってきている。このため今後は機体システム全体での騒音低減に取り組む必要がある。航空機の騒音がどこから放射されているのかを正確に把握するため、我々は実機航空機の騒音源探査に取り組んでいる。地上に設置した多数のマイクロフォンにより航空機の上空通過時の音響信号を収録し、それぞれのマイクロフォンへの到達時間の差から、音の発生位置を逆算する解析手法である。この解析の際にはマイクロフォンと航空機との相対位置および相対速度が重要になってくるが、列車や自動車と違って航空機は毎回同じ経路と速度で上空を通過することは困難なので、これらの計測を正確に行うことが重要になってくる。本研究では地上に設置した2台のラインスキャンカメラにより、ステレオ撮影法の原理を用いて航空機の3次元的な通過位置および通過速度を自動解析することを目的とする。この計測システムを実際の飛行試験に適用し、レーザー測域センサおよび機体搭載GPSによる計測との比較を行ったので、その結果を報告する。

著者

長井 健一郎 生沼 秀司 石井 達哉

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.2010, pp.171-172, 2010

被引用文献数

3

---

世界的な環境問題への関心の高まりと、今後見込まれる航空輸送量の増加より、航空機の騒音規制はますます厳しくなるものと予想される。航空機騒音の主な要因はエンジンからの騒音であるが、近年ではターボファンエンジンの高バイパス比化により低騒音化が進み、相対的に高揚力装置や離着陸装置など機体から発生する騒音が顕著になってきている。このため今後は機体システム全体での騒音低減に取り組む必要がある。航空機の騒音がどこから放射されているのかを正確に把握するため、我々は実機航空機の騒音源探査に取り組んでいる。地上に設置した多数のマイクロフォンにより航空機の上空通過時の音響信号を収録し、それぞれのマイクロフォンへの到達時間の差から、音の発生位置を逆算する解析手法である。この解析の際にはマイクロフォンと航空機との相対位置および相対速度が重要になってくるが、列車や自動車と違って航空機は毎回同じ経路と速度で上空を通過することは困難なので、これらの計測を正確に行うことが重要になってくる。本研究では地上に設置した2台のラインスキャンカメラにより、ステレオ撮影法の原理を用いて航空機の3次元的な通過位置および通過速度を自動解析することを目的とする。この計測システムを実際の飛行試験に適用し、レーザー測域センサおよび機体搭載GPSによる計測との比較を行ったので、その結果を報告する。

著者

小村 啓 大岡 昌博

出版者

一般社団法人 日本機械学会

雑誌

IIP情報・知能・精密機器部門講演会講演論文集 2014 (ISSN:24243140)

巻号頁・発行日

pp._G-1-4-1_-_G-1-4-2_, 2014-03-18 (Released:2017-06-19)

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In virtual reality (VR) study, there are two ways active and passive touches to explore a virtual object with the tactile mouse. There is an issue "which is superior active or passive touch?" The active touch is to touch and perceive an object actively, while the passive touch is to touch and perceive a change of an object passively. The purpose of this study is to evaluate a perception precision in active and passive touches to clarify the best exploration method. This experiment is exploring the degree of leaning of the edge line using the tactile mouse in the virtual space. We develop a new tactile display called a palm tactile mouse and evaluate the perception precision using an angle difference-threshold and a judgment probability-function calculated by constant method of the psychophysical experiment. As a result, we confirmed that perception precision is the best when explore speed is 90 mm/s, and the active touch is not different from the passive touch.

著者

畠山 貴充 平野 幸助 中村 雄太 藤澤 彰宏 土屋 貴司 山口 達也 千田 有一 吉村 達也

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.851, pp.16-00531-16-00531, 2017 (Released:2017-07-25)

参考文献数

21

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In the present paper, development of an automatic spinach harvester is discussed. Our research group has been developing a prototype harvester and many filed tests have been successfully executed. The field test results show that spinach can be picked up automatically without being grasped after their roots being cut at specified position in soil. The harvester equips two degrees of freedom control units, such as the arm length control unit and the arm angle control unit, for controlling a root-cutting blade which follows the specified path under the ground. In the present paper, modeling and control design for the arm length control is discussed. First, a control design model is developed by several system identification techniques. Next, an I-PD controller is designed by the robust control design procedure. Control performance is verified by numerical simulations and field tests.

著者

朝岡 忠 水内 郁夫

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.851, pp.16-00483-16-00483, 2017 (Released:2017-07-25)

参考文献数

41

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This paper describes how to exploit the elasticity and the dynamic coupling of a multi-link robot with elastic elements to improve the motion ability without depending on only actuator power. The focus is on swing motion (e.g., throwing or kicking motion) in this paper. The prime purpose of the swing motion is to increase the kinetic energy of an end-link (e.g., hand or foot). This paper proposed a method to generate a swing motion pattern for the increase of the kinetic energy of the end-link. In general, the multi-link robot has high-power actuators in the base side. The high-power actuators can produce a large amount of mechanical energy. Mathematical models were constructed to transfer mechanical energy from the base side toward the end side by exploiting the elasticity and the dynamic coupling. The swing motion pattern was generated on the basis of the models. The results of simulation experiments showed that the kinetic energy of the end-link increased explosively. The reason was that a large amount of energy produced by the actuators in the base side was transferred toward the end side.