Citation

Cai Y. Transp. Res. Proc. 2024; 78: 594-601.

Copyright

(Copyright © 2024, Elsevier Publications)

DOI

10.1016/j.trpro.2024.02.074

PMID

unavailable

Abstract

The reduced auditory detectability of electric vehicles (EVs) at low speeds has elicited concerns for pedestrian safety. In shared space where traffic regulations and physical separations are absent, the auditory perception of approaching vehicles from behind is a critical factor in preventing pedestrian-vehicle collisions, for both sighted and (blind) visually impaired people. This study explored the effects of the sound pressure level of background noise, vehicle type, vehicle manoeuvre and approaching direction on auditory perception. Vehicle sounds were recorded in a car park under controlled driving behaviour, and the background noise was recorded in a typical shared space. These sounds were then synthesized and reproduced in an anechoic chamber. 9 participants were presented with 48 sound cues. Their auditory perception was assessed by detection rate, direction determination, and detection distance of approaching vehicles.

RESULTS indicate that only 6% sound cues were missed by participants and it happened mostly at the highest background noise level (69 dBA), and all reported instances of approaching direction were accurately identified by the participants. All aforementioned factors were found to have a significant impact on detection distance. A regression model was also conducted and shows relative high prediction power for the detection distance (adjusted R2=0.703). The comparison between stopping distance and detection distance showed that in many experimental conditions, approaching conventional vehicles could be detected away from the stopping distance while electric vehicles could not. This paper proposes a conceptual framework for understanding the role of auditory perception in EV-pedestrian interactions, and the pilot lab experiment suggests that the quietness of EV may cause safety issue for pedestrians in shared space.

Language: en

Keywords

Auditory perception; Detection distance; Electric vehicles; Pedestrian safety; Shared space