著者

長屋 幸助 小島 多香子 細谷 俊介 葛 徳梁 安藤 嘉則

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.2004, pp."753-1"-"753-6", 2004-09-27

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Changing diapers hurts prides of the patient, so that a panty type toilet that can be worn to the patient is of importance., in which feces and urine are washed automatically. One of the panty type toilets has been reported. In the report, however, the principle of the toilet was only discussed, and so it cannot be used in practice, because of lack of production process. In addition, since the clamp up pressure to the body was not controlled, it often gives pains to patients. The present article gives a method of producing the panty type toilet, and a new rotary type electromagnetic valve, and a method of pressure control is presented. To have cheaper toilet, this article also provides a device of detecting faces and urine by using a humidity sensor. Some demonstrations are performed for the toilet made in this experiment.

著者

フレディアント 梶山 拓也 吉田 準史

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.2019, 2019

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<p>Vibration reduction of vehicle is essential to improve the ride comfort. For evaluating the ride comfort, the vehicle vibration is occasionally analyzed in time domain. In this study, we propose a method to obtain the high contributing vehicle body vibration behavior deteriorating the ride comfort at a transient condition in time domain. We considered and applied two methods to realize the time domain analytical method. In the first method, we applied principal component (PC) analysis to the time domain vibration acceleration signals of the multiple body points at the transient condition to obtain the important vibration behavior. In the second method, we applied the PC analysis to the frequency domain signals and re-generated time domain signal by inverse FFT (IFFT). Through a simple vehicle vibration test at a transient condition and the comparison of the result, both methods were found to have ability to extract the high contributing body behavior at the transient condition but the second method utilizing IFFT was clarified to be more useful and accurate method.</p>

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

辻本 直樹 浅見 敏彦 伊勢 智彦 坂本 博哉

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.2009, pp._463-1_-_463-6_, 2009

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In this paper, we show various dynamic properties of an air spring which has an air stream passing through a narrow tube to the air reservoir. Experimental apparatus is a single-degree-of-freedom system, which is composed of a mass supported by the air spring. Thus the only one resonance point is appeared in the response curve when the extreamly narrow tube (d=2.5mm) is used. However, when we use a more thick tube (d=4.0mm), two response points are appeared in the curve. It will be shown that the resonace point is caused by the change of the spring constant of the air spring.

著者

田中 大輔 石光 俊介

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.2016, 2016

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<p>Every year the City of Hiroshima holds the Peace Memorial Ceremony to console the souls of those who were lost due to the atomic bombing as well as pray for the realization of everlasting world peace. Since the ambient noise of this ceremony is very loud, these noise was tried to reduce using a passive method and Active Noise Control (ANC). There are some problems that audiences or TV crews cannot catch the meanings of presenter's messages such as the Prime Minister's, because of ambient noise. To reduce these noises, tents were prepared in the venue. There were also useful for protect people from the strong suns. The difference between the sounds near the loudest place in the park and those in the venue was measured to confirm the effectiveness of each countermeasure. The one of the loudest noise came from an opposite bank of the river. Though the noise was detected at the river side, it was not detected in the venue. As a result, the noise in the venue was reduced by 15 dB owing to each countermeasure. As most of the noise are speech, a 6-second young woman's voice was used as the noise source and reference signal in the ANC test of this study. Noise source includes the high frequency components up to 4000Hz. High-speed signal processing was required to reduce the noise that has high frequency components and changes its amplitudes rapidly. FPGA with a clock of 40MHz was selected for the fast signal processing. Filtered-x LMS algorithm was used in the ANC, and sampling frequency was 15 kHz and adaptive filter coefficients were set to 3000 tap. As the results of control, the noise was reduced by 10dB in 500Hz to 5000Hz.</p>

著者

鈴木 嵩之 折原 悠太 大石 久己 長谷川 浩志 岡村 宏

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.2018, 2018

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<p>We have studied the sound quality improvement of the classical guitar. The running-in of really playing on the guitar as well as the manufacturing process of guitar gives the large influence to the sound quality. It is called an aging effect. It is important that the behavior of the aging effect is considered on the manufacturing process. But the result of over-aging treatment causes, sometimes, the poor sound quality. The mechanism of over-aging is open here.</p>

著者

面田 雄一 中島 求

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.2004, pp._706-1_-_706-6_, 2004

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The objective of this study is to clarify the principle of the most stable position in the skydiving freefall. As the first step, the simulation method to analyze the dynamic behavior for freefall has been developed by the authors. In this report, an optimizing calculation to maximize an objective function with respect to the stability in the freefall is conducted. It is found that the most stable position becomes arched one. Next, the simple configuration that consists of 20 cylinders is optimized, and the angle to maximize restoring moment about each cylinder element is calculated and compared with optimized angle.

著者

富田 直 西垣 英一 表 竜二

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.2019, 2019

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<p>Lightweight structure is required due to ecological considerations. However, the lightweight requirements conflict with noise and vibration (NV) performance. To satisfy both of lightweight solution and NV performance, vibration reduction based on periodic structures is of interest because the periodic structures have wave filtering characteristics which inhibit elastic wave propagation at the frequency ranges referred as band gaps.</p><p>This paper presents a vibration reduction method using the band gaps of periodic shell structures. The frequency of band gaps can be calculated by using reduced FEA model which is applied the Bloch's theory. We can design shapes of unit cells using the calculated band gaps which relate to frequency range with vibration reduction. Frequency response of a finite periodic shell is carried out to demonstrate vibration reduction based on the band gaps. The results of analysis suggested that the band gaps of periodic shell restrain formation of natural vibration.</p>

著者

若松 武史 小野 精悟

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.2007, pp._802-1_-_802-5_, 2007

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Being capable of highly accurate measurement, P.D. flowmeters have been used conventionally in such applications as custody transfer and meter proving. For more accurate measurements, servo P.D. flowmeters, in which the serve motor drives the rotors so that the pressure difference across the rotors are appropriately controlled, have taken over ordinary P.D. flowmeters. Further requirements on these meters are, however, becoming tough year after year. Demands on high precision measurement of multiple liquid types with different properties, wider range-ability, and higher response are recently required.

著者

内田 勝一 若松 武史 長田 重慶 嶋田 隆司

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.2009, pp._114-1_-_114-5_, 2009

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A positive displacement (PD) flowmeters has been used for long years as it can measure volumetric flow directly. Since features of PD's are most exerted in oil related flow measurements, in present society which environmental issues are emphasized, they are required for high accuracy fuel consumption measurements in transport equipment industry such as automotive industry, as well as assuming an important role in cross-border transactions. Also, in recent years, development of secondary standards for JCSS registration is an urgent need; verification of our Screw PD Flowmeter is made, corresponding to such necessity.

著者

中原 健志 藤本 孝

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.2011, pp._107-1_-_107-8_, 2011

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An energy regenerative active vibration control method using piezoelectric actuators, class D drivers, output filters and sliding mode controllers is proposed by the authors. DC voltage sources are used as power sources in the previous study and capacitors which can store regenerated energy also can be used as power sources. Class D drivers and output filters consist of switches and passive electric elements. Therefore, systems using capacitors as power sources can be considered as semi-active systems. Voltages of capacitors used as power sources are not constant because the capacitors are charged and discharged in control processes. An advantage of the proposed method is that characteristics of closed-loop systems are independent from voltages of power sources when systems are in sliding mode conditions. The advantage is suitable for systems using capacitors as power sources. The validity of the semi-active control method based on the proposed method is shown by numerical simulations of a SDOF model.

著者

角谷 健斗 進藤 友陽 金子 成彦

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.2018, 2018

被引用文献数

1

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<p>These days, the number of traffic accidents due to drivers' sudden diseases is increasing. Therefore, it is desired to detect sudden diseases by making use of drivers' biological signals measured while driving. To detect such diseases, we need to know how biological signals change with the disorders. However, it is difficult to measure physiological signals at sudden diseases and propose the method for detecting such conditions. In this study, we construct a cardiovascular model which can reproduce mechanism of a cardiovascular system, and calculate biological signals by assuming sudden diseases in the model. In the cardiovascular model, stroke volume, the blood volume pumped by a heart per beat, is determined based on the operating conditions of the system. Besides, we considered positions of baroreceptors and pressure sensors of a cardiac system in blood vessels. Then, we succeed to construct detection method for sudden diseases based on the calculated biological signals. We use K-nearest method and LOF method for a detection algorithm and found that combination of systolic blood pressure and heartbeat interval is adequate for detection, and LOF method is useful for the discrimination of disease.</p>

著者

萬 礼応 谷川 あゆみ 高橋 正樹

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.2017, 2017

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In this paper, dual-task performance assessment robot (DAR) using projection is developed. Falling is a common problem in the growing elderly population. Fall-risk assessment systems have proven to be helpful in community-based fall prevention programs. One of the risk factors of falling is the deterioration of a person&rsquo;s dual-task performance. For example, gait training, which enhances both motor and cognitive functions, is a multi-target stepping task (MTST), in which participants step on assigned colored targets. To evaluate the dual-task performance during MTST in human living space, projection mapping and robot navigation to maintain a safe distance from the participant are key technologies. Projection mapping is used to evaluate the long-distance dual-task performance, where MTST target images are displayed on the floor by the moving DAR. To evaluate the accuracy of the projected target position, experiments for MTST target projection using the moving DAR and video analysis are carried out. Additionally, to verify the validity of the MTST by the moving DAR at a constant speed, experiments with several young participants are carried out.

著者

平田 昌大 佐藤 康三 松山 祥樹

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.2010, pp._641-1_-_641-5_, 2010

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This research is universal design for electric kettle of the usability and safety. It analyze the position of the gravity and knob for electric kettle, and discover the problem in fuman engineering of a current products. The relation of product and human is chenge like same to the age change. A lot of products what shoul be the review for the relation to the most important body when the tool is used like an electric kettle exist in all place. If an appropriate relation of the thing can keep being created always, The original role of the products "It is improved the quality of the life of man" might be demonstrated enough.

著者

櫛田 果鈴 齋藤 優里 菅原 佳城 坂間 清子 春山 純一

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.2018, 2018

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<p>This paper describes behavior of the jump robot which is connected by tether. The internal environment of the hole existing on the moon is not clear and is expected to be investigated. For research of the unknown environment, exploration is planned using a rover with umbilical tether connecting a mother rover near the hole. Then, it is important to study how tether influences jumping behavior of the rover. Equation of motion and differential algebraic equation is formulated by the use of Absolute Nodal Coordinate Formulation (ANCF) and multibody dynamics. Rover is regarded as two bodies with slider joint. Telescopic motion of spring expresses effect of jump. Numerical analysis reveals the relation of jumping behavior and parameters, and is compared with experimental result.</p>

著者

杉山 博之 須田 義大

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.2006, pp._204-1_-_204-6_, 2006

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次世代のマルチボディ動力学解析において期待される非線形有限要素法との連成問題,つまり,剛体,柔軟体および大変形柔軟体がジョイント拘束を介して連成した多体拘束系動力学問題の効率的な数値定式化手法の開発が活発に行われている.特に,マルチボディ計算アルゴリズムにて用いられる非増分型アルゴリズムに基づく非線形有限要素法, Absolute nodal coordinate formulationがShabanaによって提案されており,大変形柔軟体を含むマルチボデイシステムの拘束系動力学解析に適用されている.しかしながら,本定式化の曲がり梁としての特性に関してはほとんど報告されていない.また,既存の3次元Absolute nodal coordinate formulation梁要素では,体積要素としてGreen-Lagrangeのひずみテンソルから弾性力を導出しているため,せん断変形および断面変形に起因したロッキングが発生する.特に,梁が初期形状において曲率を有する曲がり梁においては,ロッキングの影響が顕著となり精度の低下を招く.本論文では,図A1に示すような大変形柔軟マルチボディ解析における曲がり梁の新たな定式化手法を提案した.曲がり梁の軸曲線に沿ったひずみ成分を,基準および変形後の配置に対する変位勾配変換と基準配置にて一義的に決定するAlmansiひずみにより表すひずみ式を導出した.また,曲がり梁の回転ひずみ成分を曲率/ねじりテンソルにより定義することにより,既存の定式化にて問題となる体積要素として導出される曲げひずみ成分の精度低下を回避した.さらに,せん断ロッキングをHellinger-Reissner混合変分原理を用いて回避し,また断面変形に関してAssumed strain法を用いてメンブレンロッキングを回避して要素精度を向上させた新たな曲がり梁の定式化を示した.図A2に示す梁のロールアップ問題に対する理論解との比較および図A3に示す動的スティフニングに関するベンチマーク問題を用いた要素精度の検証から,大変形曲がり梁を有する機械構造物の工学的動力学問題に対して,提案した手法が有効であることを示した.

著者

高橋 勝美 坂元 孝子 山本 圭治郎 兵頭 和人 八高 隆雄

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.2005, pp."529a-1"-"529a-5", 2005-08-22

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This study was to examine the optimum height of chair for standing up operation and to inspect the shake of the center of sole pressure and the characteristics of EMG during the standing movement. Standing movements performed at the height of seating posture (hip, knee and ankle joint were 90 degree), and at he height of ±2%, ±4% and ±6% of the seating posture. The center of sole pressure was measured by a force-plate and the EMG's of the muscles of lower limb were measured. The shake of the center of sole pressure was larger at higher sitting height, on the other hand, the EMG activity was larger at lower sitting height. The large shake of the center of sole pressure means the large transfer of center of Gravity, consequently the posture of standing up operation from high chair decreased the load of lower limbs.

著者

延廣 良香 向井 美紀 小倉 由美 藤田 悦則 村田 幸治 亀井 勉 辻 敏夫 金子 成彦 吉栖 正生

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.2011, pp._207-1_-_207-10_, 2011

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For the homeostatic control, there are Ultra Low Frequency (ULF) fluctuations on the backbone of the control. We think we can extrapolate state of human by capturing variation of ULF fluctuations. In this study, a method was conceived for capturing ULF fluctuations by performing the time series of the gradients analysis of the pulse wave taken from the surface of the back, which was defined as an aortic pulse wave (APW) with zero-cross detection method or peak detection method. APW was recorded during an experiment with an induced sleep test in the sitting position. The results indicated that we can find drowsiness, a predictive signal for falling asleep and an impending sleep by catching variability of 0.0017Hz, 0.0035Hz and 0.0053Hz of ULF fluctuations of APW obtained by the analytical method we had invented.

著者

サヒン ハカン 福島 直人 萩原 一路

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.2010, pp."543-1"-"543-6", 2010-09-14

著者

相原 洋人 田中 信雄

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.2007, pp."340-1"-"340-6", 2007-09-25

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There have been a number of reports on active noise control (ANC). However, conventional ANC using a voice coil loudspeaker promises attenuation only at targeted local points. Then ANC using a parametric array loudspeaker as a control source is discussed. A parametric array loudspeaker exploits nonlinear interactions of finite amplitude ultrasounds in the air. Characteristics of a parametric array loudspeaker have already been reported by a number of researchers. However, there are few investigations of simulation or experimental result of ANC using a parametric array loudspeaker. This paper addresses control effect of feed forward ANC using a parametric speaker as a control source. The control effect is more than 20dB by ANC using a parametric array loudspeaker as a control source at 1000Hz. Distribution maps of sound pressure of ANC using a conventional speaker and a parametric speaker as a control source are shown by numerical analyses and experiments.