著者

山本 広樹 青島 伸治

出版者

The Society of Instrument and Control Engineers

雑誌

計測自動制御学会論文集 (ISSN:04534654)

巻号頁・発行日

vol.39, no.11, pp.993-1001, 2003 (Released:2009-03-27)

参考文献数

12

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In this paper, we propose evaluation indices for grasping the characteristics of measurement signals from three axis sensors. Those evaluation indices are based on signal representation of quaternion and spectral analysis on the form. And, those are led by linking the coefficients of such spectra and the concept of the periodic motion on elliptic orbit in quaternion space. To show the benefit of the method in future use, an model experiment processing the three axis acceleration measurement data, which were recorded by originally developed sensor ball, were carried out. Then, the indices were calculated with the acceleration data given in such manner. As the result, comparing to the complex spectra at each axis, our evaluation indices have some advantages at the point of quick observation and recognition of three dimensional dynamical characteristics. Although the data processing based on quaternion has been widely used among the field of computer graphics or attitude control system of artificial satellite, a few attention are paid to the application for the signal processing of three dimensional measurement signal. On the other hand, in the field of the diagnostics with vibration such as of rotating machine, the spectral analysis which can observe a phase relation between multiple axis may become to be in great demand. So that, our evaluation indices will be a useful mean under such situation.

著者

久保 和良 青島 伸治

出版者

The Society of Instrument and Control Engineers

雑誌

計測自動制御学会論文集 (ISSN:04534654)

巻号頁・発行日

vol.31, no.6, pp.712-721, 1995-06-30 (Released:2009-03-27)

参考文献数

22

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Piano and guitar tone decay analysis has been carried out using reverberation responses calculated by Wigner distributions. The responses are investigated in comparison with record of the conventional short time spectra. The reverberation responses which are intimately related with the internal energy of instrumens represent 1) the envelope of tone decay without fluctuation induced by interference, reflect 2) mutual load effect associated with the oscillators, thus, clearly show 3) the gradients of energy decay curves, and are 4) less influenced by window function length. A guitar under investigation is shown to provide 1) two-step tone decay curve not caused by difference between decay rates of horizontal and vertical vibration modes of the strings (single string tone), and 2) multi-step energy curve with each step having much longer duration than the interference period (two string tone).On the other hand, the analysis of a grand piano reveals the following features:1) two power peaks in the spectra of aftersound are caused by different reasons from each other, 2) multistep energy decay curve is altered by performance style or piano condition, and 3) the partials are exhausted after absorbing energy of the other vibration modes.

著者

山本 広樹 青島 伸治

出版者

計測自動制御学会

雑誌

計測自動制御学会論文集 = Transactions of the Society of Instrument and Control Engineers (ISSN:04534654)

巻号頁・発行日

vol.39, no.11, pp.993-1001, 2003-11-30

被引用文献数

1 1