Perception of azimuth angle of sound source located at high elevation angle: Effective distance of auditory guide signal

摘要

In Japan, auditory guide signals are commonly installed in public spaces to lead visually handicapped pedestrians to their destinations. The sound sources of the signals are usually installed at high places on walls. In other words, the sound sources have not only an azimuth angle but also an elevation angle when viewed from the users. in the present study, under the hypothesis that the horizontal localization error increases with increasing elevation angle of the sound source, a sound localization test allowing head movement was performed to clarify the upper limit of the elevation angle. The results of the test were consistent with the hypothesis and indicated that the upper limit of the elevation angle was 65 within the range of the signal used in the present study and the assumption that the correct discrimination of eight directions is sufficiently accurate in the application of auditory guide signals. Furthermore, the effective distance of auditory guide signals, that is, the closest distance that users can approach to the destination using the signals was Studied on the basis of the results of the present study. As a result, it was found that the effective distance of auditory guide signals does not exceed 1 m, in other words, the signals work effectively in the range horizontally farther than 1 m, when the height of the sound source is less than 3 m. (C) 2019 Elsevier Ltd. All rights reserved.