Ultra Low Cost Infrasonic Acoustic Sensors

G. Srinivas
TDA Research Inc, Colorado, United States

Keywords: Infrasound, low frequency, acoustic, sensor, low cost, dense array

TDA Research, designed, built, and tested a dense array of 100 very low cost infrasonic acoustic sensors. Due to their low cost (1/100x-1/10x the cost of other infrasound sensors), they can be economically deployed in very large number. These sensors measure infrasound from 0.1 Hz-100 Hz down to 0.08 Pa. They can be used to detect and locate any phenomena that generates infrasound including volcanoes, avalanches, tornadoes, explosions and nuclear tests. We tested the sensors in small sub-arrays (N=4 to N=12) with higher frequency signals (30 Hz-80 Hz) and in a full array of 100 sensors with very low signals using a rotary subwoofer (2 Hz-20 Hz). The sensors performed extremely well, recording all of the signals that we tested them with. A dense array of many infrasound sensors will have significant advantages to a sparse array. Data can be collected on a more granular level, providing information on how infrasound propagates through space over time within small distances and short time frames. Overall, this project shows that we can design, build, and network together a dense array of a large number of very low cost infrasonic acoustic sensors.