Airborne drones are becoming commonplace, especially in the military. But what about seaborne drones? Swarms of autonomous vehicles out in the ocean could help monitor coastlines or dangerous passageways rife with pirates.

To that end, the Department of Defense wants to seed the oceans with robotic vehicles, leaving them on the seafloor until they’re needed. In a time of crisis, a military commander would transmit a signal to the underwater vehicles, which would then float to the surface and either monitor the area, or launch a separate unmanned vehicle into the air to gather intelligence. At the end of the mission the vehicle could be picked up by a submarine or support ship. The system of robotic vehicles and their UAVs would be called Upward Falling Payload.

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The Defense Advanced Research Projects Agency is asking private companies to come up with designs for the communications systems, the “risers” that will float the UAVs to the surface, the UAVs themselves and the equipment they would carry.

Such an arsenal of autonomous vehicles would have to survive for a long time — perhaps years — at the bottom of the ocean in cold, corrosive seawater unfriendly to metal and electronics. Communications will also be a challenge, because only very low frequency radio waves can penetrate ocean depths. The wavelengths are so long that the amount of data that can be transmitted is limited, so any complicated communications — beyond the “float to the surface” signal would probably have to be transmitted from a done at or near the surface.

On the other hand, Lockheed Martin designed an unmanned vehicle called the LMSW Cormorant that does something similar to what DARPA is asking for. So it’s certainly possible, though nobody has flown anything like it yet.

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The non-technological questions include just how many seaborne drones would be needed and in what circumstances would they be called to duty. A strategist from 1998 might have predicted that drones would be needed in the Adriatic, near the Balkans. In 2008, the answer might be in the Persian Gulf, or perhaps the Taiwan Straits, or in the Sea of Japan near North Korea.

Accounting for both present and future needs is a major challenge, even if DARPA can develop swarms of these robots cheaply.

Via DARPA, Aviation Week

Credit: Lockheed Martin