著者

栗原 昇 寺尾 吉哉 中尾 晨一 高本 正樹

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.65, no.637, pp.3029-3034, 1999-09-25 (Released:2008-03-28)

参考文献数

10

被引用文献数

3

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A calibrator of laser Doppler velocimeters (LDVs) has been developed as the measurement standard of flow velocity. This calibrator has a rotor with single fine wire and generates various velocities from the rotation. To minimize the influence of wire deformation, the orbit diameter in movement was measured with an interferometer as the distance of a rotor traversing. A measurement control volume of tested LDV was used to detect the wire orbit position. The calibration factor of tested LDV was decided as a ratio of wire velocity to the average frequency of the Doppler burst signal. In this paper, the uncertainty of LDV calibration with this calibrator was analyzed and unknown sources were quantified by the experiment. The maximum uncertainty source was pitching of the carriage table, which would be reduced by remodeling of the devices. The combined standard uncertainty of the calibration was about 100 ppm in the velocity range of 2 to 30 m/.

著者

佐藤 運海 竹ノ内 敏一 原 宏 山崎 隆夫 若林 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.71, no.710, pp.3074-3080, 2005-10-25 (Released:2011-03-04)

参考文献数

7

被引用文献数

8 8

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This paper describes development of end milling of carbon steel by electrolyzed reduced water of dilute sodium chloride solution, instead of conventional cutting with cutting fluid which is not environmentally consciousness. First, experimental equipments were built with a machining center, cutting fluid supply system made from the bath pump, temperature sensor and temperature recorder etc., and end milling processing of carbon steel was performed using electrolyzed reduced water of dilute sodium chloride solution and conventional cutting fluid respectively. Next, measured surface roughness, evaluated surface deterioration layer, temperature change of work piece and wear state of end milling. As the results of all evaluations above-mentioned, there is no difference between the end milling process using electrolyzed reduced water and that of conventional using cutting fluid. It is supposed electrolyzed reduced water instead of cutting fluid is environmentally consciousness process.

著者

横山 誠 Hedrick J.K. 外山 茂浩

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.657, pp.1449-1454, 2001-05-25 (Released:2008-02-26)

参考文献数

11

被引用文献数

8 8

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This paper presents a new sliding mode controller based on the theory of model following control for semi-active suspension systems with Magnetorheological (MR) dampers which have undesirable nonlinear properties. In the proposed controller, a desired semi-active suspension system is chosen as the reference model to be followed, and the control low is determined so that an asymptotically stable sliding mode will occur in the error dynamics between the plant and the reference model states. The advantages of the proposed controller are : (1) measurement of the damping force is not required, (2) the reference model specifies the desired performance considering the passivity constraint of the damper, (3) it is highly possible to maintain the sliding mode and achieve high robustness against the nonlinear properties of the damper. Numerical simulations illustrate the effectiveness of the controller.

著者

波多野 元貴 鈴木 重行 松尾 真吾 片浦 聡司 岩田 全広 坂野 裕洋 浅井 友嗣

出版者

一般社団法人 日本機械学会

雑誌

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2012 (ISSN:24329509)

巻号頁・発行日

pp.430-435, 2012-11-14 (Released:2017-06-19)

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The purpose of this study was to clarify the time course of the stiffness of the hamstrings, range of motion (ROM), stretch tolerance, and isometric peak torque (IPT) of knee flexor after a 5-min static stretching for hamstrings. In 24 participants, static passive torque, representing resistance to stretch, was also measured using an iso-kinetic dynamometer and decreased after stretching on all of experiments. On three different days, dynamic passive torque (DPT) and IPT were measured before and 10, 20 or 30 min after stretching. As a result, ROM and maximal DPT were significantly increased and also IPT was significantly decreased at 10, 20 and 30 min (P< 0.05, respectively) after stretching. Although the stiffness was significantly decreased at 10 and 20 min after stretching (P< 0.05, respectively), this effect recovered within 30 min. These results showed that the retention time of the effect of stretching on stiffness was shorter than the retention time on ROM, stretch tolerance, and IPT.

著者

岡田 光貴 末岡 裕一郎 中西 大輔 大須賀 公一

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

pp.19-00151, (Released:2019-12-04)

参考文献数

13

---

This paper is concerned with the demonstration of scallop-like swimming with the aid of robot toy; using jet propulsion by clapping the shells quickly. Previous works from biological approach have indicated what structures contributes to generate the jet propulsion. This paper tries to perform quick underwater locomotion by mimicking the structures of scallop based on constructive approach: development of scallop-like robot with autonomous generation of jet propulsion. After designing the structure and actuation mechanism by mimicking the scallop, we focus on the effect of the mantle property on swimming. Firstly we confirm that developed robot can perform scallop-like swimming. Secondly we also compare the swimming speed by changing the property of designed mantles.

著者

忠地 憲司

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.104, no.992, pp.477, 2001-07-05 (Released:2017-06-21)

著者

安田 仁彦 神谷 恵輔

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.515, pp.1609-1615, 1989-07-25 (Released:2008-02-21)

参考文献数

21

被引用文献数

1 1

---

As a basis for developing an identification technique of nonlinear distributed systems based on their dynamical responses, an identification technique is proposed based on a simple example of nonlinear distributed systems. The example taken up is a simply supported beam vibrating with large amplitudes. The basic procedures of the proposed technique are: (1) measuring periodic responses of the beam to periodic excitations; (2) determining modal coordinates using the responses based on the modal functions of the corresponding linear beam; and (3) determining the modal equations including nonlinear terms using the principle of harmonic balance. Some numerical examples are given, and the technique proposed is shown to be applicable.

著者

木下 泰宏

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.80, no.810, pp.LH0036, 2014 (Released:2014-02-25)

参考文献数

40

---

The purpose of this paper is to clarify the factors which influenced the development of the technology in the Edo period. Especially, this paper tries to consider the influence on the mechanical technology development by the “Shinki-hatto”. “Shinki-hatto” law was promulgated in 1721. It has been proposed in the field of the history of engineering and intellectual property that invention is strictly prohibited by this law and the law causes Japan's stagnant technology development in the Edo period. This paper makes clear that the principal purpose of the law was to maintain the economic and institutional status quo. In addition, the paper suggests the possibility that the law fell short of expectations in terms of effectiveness.

著者

金子 昌太郎 奥山 淳

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 2019.25 (ISSN:24242691)

巻号頁・発行日

pp.19G02, 2019 (Released:2019-09-25)

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The reaction wheel is a mechanical device for stabilizing the posture of the controlled object by the reaction torque generated when the flywheel is rotated. When applying the reaction wheel to the controlled object, it is necessary to determine the appropriate size of the flywheel, the position to be mounted, the required torque, and so on. However, research on the size and installation position of the flywheel has not been conducted. Therefore, in this study, we construct a model of reaction wheel system on Gazebo which is a 3D dynamic simulator equipped with multiple physical engines. And, we change the various conditions of the flywheel using the model built on Gazebo and consider the influence on posture stability. In addition, by using a robot operating system (ROS) having a coordination function with Gazebo, we control the reaction wheel system on Gazebo.

著者

中田 金市

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.59, no.449, pp.507-513, 1956-06-05 (Released:2017-06-21)

著者

森上 雄太 中山 裕太 高木 健 石井 抱

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.819, pp.DR0322, 2014 (Released:2014-11-25)

参考文献数

15

---

This paper describes a monocular stereo system that can switch its viewpoint hundreds of times of more in a second using a four-pinhole viewpoint switching iris mechanism. Our system can measure the three-dimensional information of a moving object correctly using two different viewpoint images, which are selected from the four switched viewpoint images in a short interval using a four-pinhole viewpoint switching iris mechanism, corresponding to the moving direction of the object. Using a prototype of monocular stereo system that consists of the four-pinhole viewpoint switching iris mechanism and an offline high-speed video camera, we verified its effectiveness in monocular stereo measurement by performing several experiments of moving objects.

著者

江波戸 明彦

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.117, no.1150, pp.608-609, 2014

著者

岡野内 悟

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.J2010202, 2018 (Released:2019-03-25)

著者

倉迫 涼一 大日方 五郎 鳥谷 和史

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.800, pp.991-1002, 2013 (Released:2013-04-25)

参考文献数

13

被引用文献数

1 1

---

Lightening each part is needed as one method to improve the Fuel Economy of the car. On the other hand, a certain amount of mass is required for the brake rotor as thermal capacity because the main role of the brake is to convert the kinematic energy of the vehicle into the frictional thermal energy for decelerating the vehicle. Therefore, the appropriate heat design becomes important aiming at lightening brake parts. Many thermal analyses to design the strength and the cooling performance concerning the brake rotor are done. However, there are a few papers that treat the relation between the thermal analysis and the brake friction force. Authors have been developed the simple calculation method of the temperature on the friction surface where the pad and rotor come in contact. Then, it is found that contact form is one of factors in fluctuating brake friction force from the bench test data and the calculated friction surface temperature. In this paper, the calculation method of two dimensional temperature distribution of the rotor is proposed. The calculated results are effective to confirm the detail of radial temperature distribution of the rotor as a short time under braking. The tested pads and rotors were analyzed by EPMA on the friction surface. These results show that a detectable amount of tin is difference. It is found that the fluctuating brake friction force has affected by the relationship between the friction surface temperature and the melting point of tin.

著者

倉迫 涼一

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:18848354)

巻号頁・発行日

vol.78, no.786, pp.462-473, 2012 (Released:2012-02-25)

参考文献数

6

被引用文献数

2 1

---

Demands to vehicles performance from environmental view points are growing these days. Lightening each part is needed as one method to improve the Fuel Economy of the car. The main role of brakes is to transfer the kinematic energy of the vehicle to the dissipative thermal energy, and accordingly to lead the deceleration of the vehicle. On the other hand, a steady braking performance is important because it drives comfortably. The appropriate design of brakes for the stable performance requires the understanding of the temperature distribution based on the analysis of heat transfer. The friction force in a brake system is generated by making contact of the pad with the rotor. This study presumed that the friction force is depending upon the temperature of the surface where the pad and rotor come in contact. This study proposed a calculation method for estimating the temperature of the friction surface. Moreover, this study conducted the experiments to compare with the estimates from the proposed method. The experimental results agree with the estimations calculated from the proposed method. Based on the temperature distribution calculated by this method, considering how the shapes of the pad have an influence on the generated brake force.

著者

木村 勇次 井上 忠信 中田 隆之 福田 又一

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.84, no.860, pp.17-00493, 2018 (Released:2018-04-25)

参考文献数

24

被引用文献数

1 7

---

Delayed fracture susceptibility of 1.8 GPa-class ultra-high strength bolts was evaluated by an outdoor exposure test. Low-alloy steel bars with a chemical composition of Fe-0.4%C-2%Si-1%Cr-1%Mo (mass%) were quenched and tempered at 500 °C for 1 h, caliber-rolled at 500 °C with a rolling reduction of 78%, in order to create fail-safe steels (FS steels) with an ultrafine elongated grain structure. Subsequently, FS steel bars were formed into JIS M12 hexagon head bolts with a nominal length of 60 mm (FS bolts). Bolt heading was performed at 700~730 °C, and screw part was formed by thread-rolling at 500 °C to maintain the ultrafine grain structure with a strong <110>//rolling direction fiber texture. Conventionally quenched and tempered bolts (QT bolts) with a tempered martensitic structure were prepared for comparison. A steel plate was fastened by the bolts on 23 April 2013, and the outdoor exposure test was started on 21 May 2013 in Miyako Island test site of Japan Weathering Test Center. The bolt fastening force was 122 kN (=0.85 σ0.2 at thread part) for FS bolts and 89 kN (=0.70 σ0.2 at thread part) for QT bolts. The outdoor exposure test demonstrated an excellent delayed fracture resistance of FS bolts at the ultra-high tensile strength of 1.8 GPa; FS bolts have not been broken for 53 months, in contrast to QT bolts exhibiting delayed fracture. Intergranular cracking along the prior-austenite grain boundaries was commonly observed in the broken QT bolts. The accelerated laboratory test using tensile tests of pre-hydrogen-charged specimens and immersion test (30 °C, pH2) showed that the FS bolts had high resistance to hydrogen embrittlement, and it was in good agreement with the result of outdoor exposure test of the FS bolts.

著者

松田 有司 伊藤 剛

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.1003, pp.408-409, 2002-06-05 (Released:2017-06-21)

参考文献数

2

著者

関口 久美 西村 正巳 沢田 勝夫

出版者

一般社団法人 日本機械学会

雑誌

日本機械学會論文集 (ISSN:00290270)

巻号頁・発行日

vol.24, no.139, pp.205-209, 1958-03-25 (Released:2008-03-28)

参考文献数

6

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It is well known that the characteristics of rubber vibration isolators depend upon their shapes. So the authors obtained experimental equations which show the variations of their characteristics in relation to the shape factor S=(cross sectional area)/(free surface area). They previously proposed the successive approximation method already on a supposition that the variations of characteristics are chiefly caused by shape effect due to their deformations. Here the more accurate approximation method is presented on a supposition that the deformed shape is a sort of rotating parabolic body. And the radius of curvature of bonded part largely influences the moduli of rubber vibration isolators, but even in such cases this calculating method is applicable.

著者

佐藤 悠 井上 健司

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.82, no.843, pp.16-00348, 2016 (Released:2016-11-25)

参考文献数

20

被引用文献数

1

---

A method for a six-legged robot of walking on terrain with various undulations by tripod gait is proposed. First the robot detects foot landing using touch sensors, and estimates the inclination angle of the ground from the landing positions; the estimated ground is called “reference ground”. Second the robot measures the inclination angle of its body using acceleration sensor. Then the legs move up and down so that the body may be parallel to and may keep a constant distance from the reference ground. If the robot encounters deep depressions or downward slopes, the robot suspends walking and actively inclines the reference ground. As a result the body inclines, and the swing leg goes further down. When the swing leg reaches the ground, the robot restarts walking. Due to the feedback gain of body orientation control, the robot does not respond to fine change of undulation. Hence the body keeps a constant orientation on short distance undulation or rugged surface, and gradually inclines its body on long distance undulation such as slopes and stairs. The ability of climbing up and down slopes and steps in longitudinal and transverse directions is evaluated by experiments. The maximum angle of climbing up slopes is 30 degree, and that of climbing down slopes is 40 degree. The maximum height of climbing up steps is 150 mm, and that of climbing down steps is 180 mm. The robot can also go through a bump of 125 mm width and 60 mm height.

著者

横山 真男 瀬田 陽平 矢川 元基

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.17-00287, (Released:2017-12-06)

参考文献数

15

---

Based on experimental observation of liquid dripping, a method to prevent liquid adhesion at the wall of cup was proposed in this paper. When water or sauce etc. is poured from edge of a cup or a pot, the liquid adheres to the wall of cup, which often makes a table or clothes dirty. To clarify the above annoying problem, the flow dripping from the cup, whose edge was shaped to have various thin channels, was observed by using high speed camera. We found the water adhesion on cup's wall reduced when the channels were located at the outside of edge of the cup.