Portable System for Detecting Infrasound

Abstract

The purpose of this project is to create a device to detect infrasound communication from elephants in order to inform handlers of possible impending aggressive behavior. Elephants often communicate using infrasound which is low-frequency sound below the threshold of human hearing. Elephants may be trying to communicate with zookeepers but the handlers are unable to hear their call. Knowing that an elephant is communicating may give handlers time to move to safety. A device is designed and prototyped that is capable of monitoring an input signal for infrasound and produces a warning alarm for handlers. This device can also record audio for long periods of time to a digital storage device. It can be utilized for other areas of study with some modification. The device is low-cost so it would be able to be procured more easily and in higher quantities than more expensive laboratory monitoring equipment. This device could also be used as an educational and research device for students studying animal behavior in the field and laboratory. Infrasound is not limited to only elephants, but hippopotamuses, rhinoceroses and giraffes also communicate with infrasound. Environmental infrasound from sources such as wind turbines, sonic booms, explosions, tornadoes, and earthquakes can also be monitored. Test results showed that the device accurately recorded low-frequency input signals. The device also was able to detect infrasound frequencies and triggered an alarm.