Sound source localization using a single-point stereo microphone for robots

In this study, a secondary sound source localizer for robot applications is developed. The purpose of using the secondary sound localizer is to assist the camera and hand manipulation of disaster-response robots. A key requirement for this application is the compactness of the input device. In this study, a single-point 13-mm diameter stereo microphone mountable on the robot hand is employed, and its observation model is developed. The localizer must be usable while the hand scans to collect visual information. This is realized by the conversion of the parameter scan in conventional parametric modeling to the mechanical scan of the hand. Another requirement is robustness against the ego noise of the robot. Two localization methods for a single-point stereo microphone that have noise-whitening functions are proposed. Experimental results show that the proposed method achieves a performance comparable to that achieved by the conventional time delay estimation approach but with a much more compact configuration.