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Final Project Search and Rescue. Objective. As part of the search and rescue contest, you will need to find a high frequency (4 – 6 kHz) sound located somewhere in the room. There will be low frequency (< 500 Hz) sound source in the room, also. . BRAINSTORMING.
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Objective As part of the search and rescue contest, you will need to find a high frequency (4 – 6 kHz) sound located somewhere in the room. There will be low frequency (< 500 Hz) sound source in the room, also.
BRAINSTORMING How can we locate a sound source?????
Sound Pressure Levels Sound pressure levels are measured in Pascals (Pa). If someone is yelling at you from 2-3 feet away that is about 1 Pa i.e. (1 Volt out of microphone) If he is speaking in a normal voice, that would be about 0.1 Pa. (100 mV out of microphone) If he is whispering (very softly) that might be 1 mPa. (1 mV out of microphone)
Path Difference Sound Source If l0 >> d, Dl = d * sin(f) l2 l0 l1 f Left Mic Right Mic d
Phase Delay • If c = speed of sound = 340 m/s, then Dt = Dl / c. • = arc_sin{(c * Dt) / d} So, how can I measure Dt????
Phase Comparison Vphase = Vdd * (Dt / T) So Dt = Vphase * T / Vdd