3D Localization of a Sound Source Using Mobile Microphone Arrays Referenced by SLAM
This enables mobile robots to combine acoustic and visual data for enhanced spatial awareness, representing an incremental improvement in cooperative sound mapping.
The paper tackles the problem of 3D sound source localization by using two robots with microphone arrays that self-localize via SLAM and triangulate sound positions in a shared map, achieving errors under 0.3 m under specific angular conditions for static and moving sources.
A microphone array can provide a mobile robot with the capability of localizing, tracking and separating distant sound sources in 2D, i.e., estimating their relative elevation and azimuth. To combine acoustic data with visual information in real world settings, spatial correlation must be established. The approach explored in this paper consists of having two robots, each equipped with a microphone array, localizing themselves in a shared reference map using SLAM. Based on their locations, data from the microphone arrays are used to triangulate in 3D the location of a sound source in relation to the same map. This strategy results in a novel cooperative sound mapping approach using mobile microphone arrays. Trials are conducted using two mobile robots localizing a static or a moving sound source to examine in which conditions this is possible. Results suggest that errors under 0.3 m are observed when the relative angle between the two robots are above 30 degrees for a static sound source, while errors under 0.3 m for angles between 40 degrees and 140 degrees are observed with a moving sound source.