POSYDON, the GPS equivalent for underwater vessels, is set for sea trials by 2018. It is being developed by the Draper group.

Although the Global Positioning System (GPS) is incredibly useful for us landlubbers and surface going ships, however since it can’t penetrate the seawater, it’s pretty much useless for submarines or UUVs.

In order to cater to the growing needs for an acoustic navigation system, the DARPA has created GPS equivalent for underwater navigation dubbed POSYDON for Positioning System for Deep Ocean Navigation and has awarded the Draper group for developing this system.

While GPS is dependent on a constellation of satellites orbiting the earth in fixed positions relative to the surface of the Earth, which essentially allow GPS receivers to triangulate the signals from these satellites to determine your exact coordinates, the POSYDON system is expected to provide the same basic functionalities, but using just sound.

The Draper group plans of setting up a limited number of long-range acoustic sources that UUVs or submarines could ping to triangulate its position without having to surface.

POSYDON is scheduled for sea trials by 2018.

Like GPS, initially the system will be exclusively used the government and by the military, and hopefully later, it will open up for civilian use.