Study of vibration and sound characteristics of a copper gong

Tsai, Gwo-Chung; Wang, Bor–Tsuen; Lee, Yeu‐Shiuan; Chang, Zhiwei

doi:10.1080/02533839.2005.9671038

Cited by 8 publications

(5 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This analysis highlights the duplication of the asymmetric modes due to asymmetries in the geometry of the instrument. These results are consistent with the experimental modal analysis previously performed by Tsai et al 22 This modal analysis allows for the identification of the location of linear modes and is therefore necessary for the location of sensor and actuator.…”

Section: A Preliminary Modal Analysissupporting

confidence: 91%

Modal active control of Chinese gongs

Jossic

Mamou-Mani

Chomette

et al. 2017

The Journal of the Acoustical Society of America

View full text Add to dashboard Cite

Instruments that belong to the gong family exhibit nonlinear dynamics at large amplitudes of vibration. In the specific case of the xiaoluo gong, this nonlinear behavior results in a pitch glide of several modes of the instrument in addition to harmonic distortion and internal resonances. This study applies a linear modal active control to a xiaoluo gong in an attempt to change its sound properties. First, a modal damping control of the fundamental mode based on a linear identification and a state space controller is applied in the small amplitude regime (no pitch glide). Results indicate that modal control influences not only the controlled mode but also the frequency components involved in distortion or internal resonance phenomena. Second, a modal damping control is performed in the large amplitude regime (in the presence of pitch glide). Results show that modal control does not affect the pitch glide. However, the controller becomes effective at a time trigger which is related to the instantaneous frequency.

show abstract

Section: A Preliminary Modal Analysissupporting

confidence: 91%

Modal active control of Chinese gongs

Jossic

Mamou-Mani

Chomette

et al. 2017

The Journal of the Acoustical Society of America

View full text Add to dashboard Cite

show abstract

“…A novel approach, which proposed in this study is adding a tradational gong geometry as air cavity to matrix material. The model dimensions is taken from the literature [30]. It is expected that the incident sound wave energy transform into vibration, and heat energy thanks to gong air cavity.…”

Section: Resultsmentioning

confidence: 99%

“…The thickness of matrix material is represented as h_matrix, and it is set as 30 mm in all models. The gong shape air cavity is obtained from the literature [30] and all dimensions are shown in Table 4.…”

Section: Design and Optimizationmentioning

confidence: 99%

Design of Acoustic Meta-surfaces for Underwater Stealth in Low Frequency Ranges

Ranjbar,

Bayer

2023

Preprint

View full text Add to dashboard Cite

In this study, it is aimed to protect underwater vehicles against active sonar systems by anechoic metamaterial coating. A mixture of matrix material with close acoustic impedance to water, resistivity to hydrostatic pressure, suitability for the marine environment, and high material loss factor are selected. At low frequencies, the inclusions in different shapes and sizes are added to the matrix material. Since solid inclusions will increase the density considerably, air cavities are preferred as inclusions. More attention is paid to low frequency absorption, especially below 1 kHz, because of advancing sonar technology. The acoustic performance of the designed models is compared in three frequency range: low (0–3 kHz), middle (3–6 kHz), and high (6–10 kHz). The designed models are constructed by considering hydrostatic pressure; hence, volume of air cavities is tried to decrease while absorption performance is aimed to increase. Therefore, a conical air cavity is optimized by chancing its dimensions and location. Also, novel approaches, gong shape air cavity, and sandglass air cavities are introduced. The results show that, not only cavity shape, but also its location and dimensions are highly influential on absorption performance. High volume air cavities increase the absorption performance at the low frequency range, but they are not effective at high frequencies. The gong shape, and sandglass air cavities shows broadband absorption, also, gong shape air cavity volume is less than literature models. Thus, its usability increases at deep waters. The results of this study provide novel underwater meta surfaces for various applications.

show abstract

“…In order to obtain the expression in the physical space of the NNM described in Eq. (7), we replace the expression (5) in the nonlinear change of variables in Eq. (3).…”

Section: A Background On Nonlinear Modesmentioning

confidence: 99%

“…Fletcher 4 showed that the pitch glide phenomenon depends on the ratio between the thickness of the gong and the height of its central shell. Tsai et al 5 performed an experimental and numerical linear analysis of a daluo. Jossic et al 6 underlined the presence of internal resonances in the xiaoluo using modal active control.…”

Section: Introductionmentioning

confidence: 99%

Effects of internal resonances in the pitch glide of Chinese gongs

Jossic

Thomas

Denis

et al. 2018

The Journal of the Acoustical Society of America

View full text Add to dashboard Cite

The framework of nonlinear normal modes gives a remarkable insight into the dynamics of nonlinear vibratory systems exhibiting distributed nonlinearities. In the case of Chinese opera gongs, geometrical nonlinearities lead to a pitch glide of several vibration modes in playing situation. This study investigates the relationship between the nonlinear normal modes formalism and the ascendant pitch glide of the fundamental mode of a xiaoluo gong. In particular, the limits of a single nonlinear mode modeling for describing the pitch glide in playing situation are examined. For this purpose, the amplitude-frequency relationship (backbone curve) and the frequency-time dependency (pitch glide) of the fundamental nonlinear mode is measured with two excitation types, in free vibration regime: first, only the fundamental nonlinear mode is excited by an experimental appropriation method resorting to a phase-locked loop; second, all the nonlinear modes of the instrument are excited with a mallet impact (playing situation). The results show that a single nonlinear mode modeling fails at describing the pitch glide of the instrument when played because of the presence of 1:2 internal resonances implying the nonlinear fundamental mode and other nonlinear modes. Simulations of two nonlinear modes in 1:2 internal resonance confirm qualitatively the experimental results.

show abstract

Study of vibration and sound characteristics of a copper gong

Cited by 8 publications

References 5 publications

Modal active control of Chinese gongs

Modal active control of Chinese gongs

Design of Acoustic Meta-surfaces for Underwater Stealth in Low Frequency Ranges

Effects of internal resonances in the pitch glide of Chinese gongs

Contact Info

Product

Resources

About