Reflection-Aware Sound Source Localization
This addresses sound localization for robots or systems in indoor settings, offering improved accuracy by incorporating reflections, though it is incremental over prior methods.
The paper tackles 3D sound source localization in indoor environments by modeling both direct and reflected acoustic signals, achieving an average distance error of 0.8m in a 7m by 7m room with 3m height, including mobile and non-line-of-sight sources.
We present a novel, reflection-aware method for 3D sound localization in indoor environments. Unlike prior approaches, which are mainly based on continuous sound signals from a stationary source, our formulation is designed to localize the position instantaneously from signals within a single frame. We consider direct sound and indirect sound signals that reach the microphones after reflecting off surfaces such as ceilings or walls. We then generate and trace direct and reflected acoustic paths using inverse acoustic ray tracing and utilize these paths with Monte Carlo localization to estimate a 3D sound source position. We have implemented our method on a robot with a cube-shaped microphone array and tested it against different settings with continuous and intermittent sound signals with a stationary or a mobile source. Across different settings, our approach can localize the sound with an average distance error of 0.8m tested in a room of 7m by 7m area with 3m height, including a mobile and non-line-of-sight sound source. We also reveal that the modeling of indirect rays increases the localization accuracy by 40% compared to only using direct acoustic rays.