Reflection-Aware Sound Source Localization

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. 8 m tested in a room of 7 m by 7 m area with 3 m 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.

Authors

• Inkyu An
• Myung-Bae Son
• Dinesh Manocha
• Sung-Eui Yoon

Keywords

• Acoustics
• Ray tracing
• Microphone arrays
• Three-dimensional displays
• Robots
• Indoor environments
• Sound Source
• Sound Localization
• Average Error
• Continuous-time
• Local Method
• Single Frame
• Source Position
• Prior Approaches
• Stationary Sources
• Indirect Signaling
• Microphone Array
• Benchmark
• Left Side
• Covariance Matrix
• Normal Vector
• 3D Space
• Singular Value Decomposition
• Time Difference Of Arrival
• Simultaneous Localization And Mapping
• Ray Path
• Particle Filter
• Order Reflection
• Specular Reflection
• General Variables
• Acoustic Materials
• Challenging Cases
• Sound Propagation