Time-frequency analysis of high-intensity, fast transient noise from power tools by analytic wavelet transform.
Kulkarni-P; Zhu-X; Kim-J
NOISE-CON 2004: Proceedings of the National Conference on Noise Control Engineering, Baltimore, Maryland, July 12-14, 2004. Burroughs C, Maling Jr G, eds., Ames, IA: Institute of Noise Control Engineering of the USA, 2004 Jul; :306-312
Using two types of portable power tools as examples, it is explained that a time-frequency analysis is necessary to properly characterize highly impulsive sound. Between the two tools, the noise generated by the impact wrench is more highly transient compared to the jigsaw noise. It is shown that the characteristics, and therefore the related risks, of such noises cannot be severely underestimated unless accurate time-frequency analysis is utilized. We propose the analytic wavelet transform as an ideal signal analysis tool to characterize such highly transient sounds. It is explained that the transform provides the advantages of both the wavelet transform and the Fourier transform. The transform can be interpreted as a transient spectral analysis, which will open up many interesting applications. While the transform can be used to study the response characteristics of any dynamic system, it is especially useful in acoustics applications because of its resemblance to the way our auditory system processes sound signal. It is our long-term plan to develop a method for quantitative risk assessment of impact noise induced hearing loss. This work summarizes the first stage of this long term effort.
Power-tools; Noise; Noise-frequencies; Noise-analysis; Noise-propagation; Impact-noise; Sound-propagation; Noise-waves; Noise-control; Work-areas; Work-environment; Workplace-studies; Hearing-threshold; Noise-exposure; Noise-levels; Noise-measurement; Noise-pollution; Noise-sources; Noise-transmission; Audiofrequency; Audiometry; Auditory-discrimination; Auditory-feedback
Structural Dynamics Research Laboratories, Mechanical, Industrial and Nuclear Engineering Department, University of Cincinnati, Cincinnati, OH 45221-0072, U.S.A.
Burroughs-C; Maling-G Jr.
NOISE-CON 2004: Proceedings of the National Conference on Noise Control Engineering, Baltimore, Maryland, July 12-14, 2004