Quadcopter tracking by acoustic sensing based on two stereo microphones

This paper describes a method for remotely tracking a quadcopter using acoustic sensors. Our method allows you to track a flying quadcopter using just two stereo microphones. The trackable area is 3 m x 5 m rectangle whose short side is a line made between two stereo microphones. In our demonstration, two microphones were set 3 m apart. Since it is not required for time synchronization between two stereo microphones, you can easily set our system to the sensing area. Furthermore, it is possible to easily expand the trackable area. Specifically, it just adds another stereo microphone. The direction of arrival of the sound source is estimated using individual stereo microphones. The position of a quadcopter is then estimated based on the triangulation principle from two stereo microphones where the higher sound level is observed. A prototype system implemented on an Intel Next Unit of Computing (NUC7iDNH) works at less than real-time (RT) factor 1.0 (RT < 1.0).