The Silent Nemo

The US Navy has revealed its latest recruit - a giant robotic spy disguised as a tuna. The robo-fish is designed to swim into enemy territory, and to guard the hulls of US boats.

It uses a robo-fin to move silently through the water - and had been dubbed 'Silent Nemo' by Navy bosses.

Researchers from the Chief of Naval Operations Rapid Innovation Cell and Boston Engineering tested the prototype at the Joint Expeditionary Base Little Creek in Virginia on Thursday.

The fish can be controlled with a joystick or be programmed to swim on its own. The unmanned underwater vehicle is able to make tight turns and move through the water quietly, making it ideal for surveillance and reconnaissance missions.

The Navy hopes it could be used to inspect the hull of a ship, check waters for threats such as mines or protrusions, deliver payloads including sonar and guidance packages, and access otherwise denied areas.

Over the past several weeks, Boston Engineering's tuna-sized device, also known as Ghost Swimmer, has been gathering data on tides, varied currents, wakes, and weather conditions for the development of future tasks.

“GhostSwimmer will allow the Navy to have success during more types of missions while keeping divers and Sailors safe,” said Michael Rufo, director of Boston Engineering's Advanced Systems Group.

The GhostSwimmer was developed to resemble the shape and mimic the swimming style of a large fish.

At a length of approximately 5 feet and a weight of nearly 100 pounds, the GhostSwimmer vehicle can operate in water depths ranging from 10 inches to 300 feet.

“It swims just like a fish does by oscillating its tail fin back and forth,” said Rufo.

Its bio-mimicry provides additional security during low visibility intelligence, surveillance and reconnaissance (ISR) missions and friendly hull inspections, while quieter than propeller driven craft of the same size, according to Navy Warfare Development Command (NWDC).

The robot is capable of operating autonomously for extended periods of time due to its long-lasting battery, but it can also be controlled via laptop with a 500-foot tether.