Probabilistic 3D sound source mapping using moving microphone array

The paper proposes a system for mapping the 3D location of a sound source using data from a microphone array, each of which gives an independent estimate of the direction. LiDAR is used to generate a 3D map of the environment and to estimate the location of the sensor in six degrees of freedom (6-DoF). By combing these modules, our system determines the direction to a sound source in 3D global space for a moving robot. From evaluation of the time series of the tracked sound stream, the position of the sound source is estimated by using the Monte Carlo localization approach. When estimated from a moving robot, an approach based on triangulation does not always adequately locate a sound source, because the estimate depends on the relationship between the location of the source and that of the moving robot. The main advantage of the proposed system is that as an audible signal is perceived, it continuously estimates the location of the source. We evaluate the system by performing an experiment using a hand-held sensor.