US military tests PSAP Voyager underwater scanner probes powered directly from the water

The PSAP Voyager hydrophones are self-contained, as they use the temperature difference in the surrounding water to power them. Until now, underwater communications have required surface or subsea infrastructure.

The Persistent Smart Acoustic Profiler (PSAP) Voyager module was developed by the US Naval Postgraduate School (NPS) and Seatrec. It is capable of monitoring and transmitting acoustic and oceanographic data in near real time. The test off the Hawaiian Islands allowed us to collect a lot of data for study.

The module uses the conversion of thermal energy from ocean water to power the onboard computer (which runs on Linux). The device’s acoustic sensors are passive. The Voyager PSAP is also equipped with means of communication with satellites and a motor for changing position. The device can be used at a depth of up to 1 km. Currently, it operates at a depth of 700 meters and has schedules for transmitting information and reaching the surface.

Conventional underwater hydrophones require the additional use of surface or submarine ships or other underwater infrastructure. The Voyager PSAP can be easily installed anywhere, starts transmitting data immediately, and does so indefinitely (at least as long as physical resources allow). The hydrophone’s autonomy revolutionizes underwater communication and sensing.

The military does not tell too much about the Voyager PSAP. The Warzone learned, in particular, about the principle of autonomous power supply from the data of the partner company Seatrec, which cooperated with the manufacturer in 2022 and later from the founder of Seatrec, Dr. Yi Chao, about satellite communications and the engine. The U.S. Navy’s announcement of the test last week did not contain technical details, and the military did not answer questions about the timing of the probes’ commissioning. It is also unclear whether other devices use this power principle.

In today’s technological world, the secrecy of military developments is quite relative. Last year top-secret US underwater drone «spotted» Google Maps. Recently, the American and European militaries have been actively developing underwater technologies to counter the navies of China and Russia.