著者

大橋 史武 梶原 逸朗

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.2004, no.10, pp.211-212, 2004-03-03

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Vibration suppression is very important to boost the performance of advanced mechatronics devices. It has been expected that technology of smart structure will contribute to the development of small and light-weight mechatronics devices with the required performance. The smart structure is composed of the piezoelectric sensor and actuator in order to reduce the structural vibration. The placement of the piezoelectric actuator and H_2 control system are simultaneously optimized based on genetic algorithm to improve the effect on the vibration suppression. It has been verified by applications with an L-shaped beam and a plate-type smart structures that an enhanced performance for the vibration suppression can be achieved by the proposed optimal design method.

著者

宮本 大資 梶原 逸朗 細矢 直基 西留 千晶

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.77, no.777, pp.1760-1771, 2011 (Released:2011-05-25)

参考文献数

11

被引用文献数

2 2

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This paper proposes a vibration testing and health monitoring system based on an impulse response excited by a laser ablation. High power YAG pulse laser is used in this system for producing an ideal impulse force on structural surface. It is possible to measure high frequency vibration responses in this system. A health monitoring system is constructed by this vibration testing system and a damage detecting algorithm. A microscopic damage of structures can be extracted by detecting fluctuations of high frequency vibration response with the present health monitoring system. In this study, loosening of bolt tightening torques is defined as the damage of the system. The damage is detected and identified by statistical evaluations of measured frequency response data with Recognition-Taguchi method.

著者

秋田 涼佑 梶原 逸朗 細矢 直基

出版者

一般社団法人 日本機械学会

雑誌

Dynamics & Design Conference 2016 (ISSN:24242993)

巻号頁・発行日

pp.343, 2016 (Released:2017-06-19)

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This paper proposes a health monitoring system for detecting a hole opened on a pipe based on laser plasma acoustic excitation and acoustic measurement. In this system, the acoustic excitation is applied to the pipe by the laser-induced plasma in the air, which is generated by a high-power Nd: YAG pulse laser. Non-contact acoustic impulse excitation can be realized by laser-induced plasma. A microphone is used for measuring the time response of acoustic pressure. In this study, the detection of the hole on the pipe is focused. The time response of acoustic pressure changes due to reflection of acoustic wave caused at the hole opened on the pipe. The position of the hole is identified by applying continuous wavelet transform to time response of with/without the hole.

著者

岩垂 素子 大橋 史武 土屋 亮 梶原 逸朗 堀江 三喜男

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.2004, no.10, pp.209-210, 2004-03-03

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H_2 controller is designed with the reduced order model of smart pantograph structure which is obtained by finite element and modal analyses. The control force is applied by the piezoelectric film actuator and the feedback signals are detected by the accelerometer in the system. The vibration response is suppressed by modal control. The placement of the piezoelectric actuator and the H_2 control system are simultaneously optimized by using GA to achieve an enhanced vibration control performance. It has been verified by simulations that the enhanced performance for the vibration suppression can be achieved by the present method.

著者

梶原 逸朗 山家 勝裕 下嶋 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.64, no.626, pp.3839-3846, 1998-10-25

参考文献数

9

被引用文献数

1

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Dynamics of multi-link manipulators are highly nonlinear and depend on the time varying configuration. This paper presents a method of gain scheduling which consists in designing an linear time invariant (LTI) controller for each operating point and in switching controller when the operating conditions change. Each LTI controller is designed based on LMI approach in which an optimization problem is defined as a mixed H_2/H_∞ control problem with pole placement. The performances of the force and the position controls are defined by the H_2 norm, and the robust stability according to gain scheduling is evaluated with the H_∞ norm and the pole placement of the closed-loop system. The effectiveness and the practicability of the proposed method are verified by both simulations and experiments with 2-link manipulator system.

著者

下嶋 浩 松永 義弘 小池 関也 梶原 逸朗

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.65, no.633, pp.1849-1856, 1999-05

参考文献数

7

被引用文献数

2

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An approach for feedback active noise control of a one dimensional duct with multiple control sources based on modal analysis is presented in this paper. Based on experimental modal analysis, the modal parameters of an acoustical system are derived from measured multiple frequency response functions. The state equation of the duct is described by the identified modal parameters. Considering eigenvectors of the acoustical system calculated by finite element method, control sources are located to the duct. A feedback active noise controller is designed based on mixed H_2/H_∞ problem in addition to H_∞ problem, preventing the increase in dimensions of the controllers. Simulations are carried out using the designed controllers. Moreover experiments are carried out using identified controllers based on modal analysis to reduce dimensions of the controllers. The desired performances are obtained by the presented approach.

著者

梶原 逸朗 福田 将直 下嶋 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.64, no.621, pp.1668-1675, 1998-05

参考文献数

5

被引用文献数

5

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Approach for modeling and feedback noise control of a one-dimensional duct based on experimental modal analysis and LMI is presented in this paper. The modal parameters of a coupled acoustical-structural system are derived from measured noise and vibration data. The state equation of the duct is described by the identified modal parameters. An active noise controller is designed based on LMI approach in which an optimization problem is defined as a mixed H_2/H_∞ control problem. The performances of the noise reduction and the robust stability are described with H_2 and H_∞ norms of the closed loop system, respectively. Frequency response shaping is performed by the presented approach with weighted modal matrix and frequency weighting functions. Simulations and experiments are carried out and the desired performances are obtained by the presented approach.

著者

宮本 大資 梶原 逸朗 細矢 直基

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C編 (ISSN:18848354)

巻号頁・発行日

vol.77, no.784, pp.4402-4412, 2011 (Released:2011-12-25)

参考文献数

8

被引用文献数

1 1

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This paper proposes a contactless vibration testing system for rotating disks based on an impulse response excited by a laser ablation. High power YAG pulse laser is used in this system for producing an ideal impulse force on structural surface without contact. The contactless vibration testing system is composed of a YAG laser, laser Doppler vibrometer and spectrum analyzer. This system makes it possible to measure vibration characteristics of structures under operation, such as vibration measurement of a rotating disk. The effectiveness of this system is confirmed by experimental and theoretical analyses. In this paper, a platter of hard disk drive is employed as an experimental object. Vibration characteristics of a rotating and non-rotating platter are measured and compared with the results of theoretical analysis.