Interactive sound source localization using robot audition for tablet devices

This paper investigates localization of sound sources in a real environment using a tablet device. For the localization, we use build-in sensors on a tablet device and additionally mount a cover with a microphone array. Because of the flat shape and limited sensor performance, the localization has mainly the following three issues; 1) the flat microphone array allows only azimuth estimation but elevation estimation; 2) the measurement noise of built-in sensors degrades the direction of arrival estimation performance; 3) the direction of arrival is not sufficient information to localize sound sources in three dimensional space to explore. To solve these issues, we propose interactive sound source localization using robot audition. For 1), we propose elevation estimation by integrating sound azimuth estimation and device motion information under an active audition framework in robot audition. For 2), we introduced a constrained optimization to robustify the direction of arrival estimation. For 3), we propose an interactive interface based on augmented reality for tablet devices, which navigates the device camera view to sound sources to explore. The proposed system was evaluated both subjectively and objectively and showed validity in real cases of sound source localization.