Helicopter Hostile Fire Indicator (HFI) Sensor Development

Acoustic directional information has always been based upon measuring the difference between sound pressure signals at different locations, just like human hearing (two ears spaced apart). A new sensor technology for battlefield acoustics has emerged that measures acoustic particle velocity instead of sound pressure. Unlike sound pressure, that is a non-directional scalar value, acoustic particle velocity is a directional vector value which can be used to measure a shooter"s location. Dragonfly Pictures, Inc. (DPI) proposes to use this novel acoustic vector sensor (AVS) as an Acoustic Hostile Fire Locator (AHFL). No known sensor is as light, 100 grams (0.22 lbs), as small, the size of a dice, and efficient, consuming less than 100 mA. It is proposed to test the sensor in a fully instrumented autonomous Vertical Takeoff and Landing (VTOL) UAS in Phase I. This prepares us to test against small arms, RPGs, MANPADS, to prove its effectiveness at detecting, classifying and locating the threat with<10 meter circular error probable at<1km range in Phase II.