Noise mechanisms in motorcycle helmet noise

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

A unique set of results on the acoustics of motorcycle helmets has been gathered during road tests on a rider wearing a representative modern helmet. The data were collected during a study of the noise which can cause hearing damage and, possibly, distraction in riders. They consisted of simultaneous measurements of noise at the rider’s ear and unsteady pressure on the helmet surface, combined with GPS measurements of rider position and speed. These signals have been analyzed to reduce the coherent structures in the turbulent flow responsible for noise generation. The identified structures appear to be produced by a vortex street shed by the motorcycle windscreen. The internal and external pressures proved to be poorly correlated over most of the frequency range, which has been identified as a result of the insertion loss of the helmet. The implications of these findings are that the majority of the variation in helmet noise is a function of such extrinsic factors as motorcycle configuration and rider build and posture. Efforts to reduce the harmful effects of noise in motorcycling should, then, move to studying the whole system of rider, helmet, motorcycle, and external environment.
Original languageEnglish
Pages (from-to)1777
Number of pages1
JournalJournal of the Acoustical Society of America
Volume127
Issue number3
DOIs
Publication statusPublished - 2010

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helmets
windshields
vortex streets
posture
sheds
internal pressure
ear
hearing
roads
insertion loss
turbulent flow
frequency ranges
damage
acoustics
causes
configurations
Distraction
Damage
Acoustics
Insertion

Cite this

Noise mechanisms in motorcycle helmet noise. / Carley, Michael J; Holt, N J; Walker, Ian.

In: Journal of the Acoustical Society of America, Vol. 127, No. 3, 2010, p. 1777.

Research output: Contribution to journalArticle

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