'Tuna Robot' built by Boston Engineering firm. - Boston Engineering
The Navy is testing a stealthy, 4 foot-long fish-shaped autonomous underwater vehicle designed to blend in with undersea life and perform combat sensor functions, service officials explained.
The so-called “bio-memetic” undersea vehicle is currently being developed as part of the Chief of Naval Operations Rapid Innovation Cell, or CRIC – a special unit set up by CNO Adm. Jonathan Greenert in 2012 to explore the feasibility of rapidly turning around commercially available technologies for Naval military use.
“It mimics a fish. It looks like a fish. We call it robo-tuna, affectionately, but it is a UUV (unmanned undersea vehicle). It does not have a propeller or a jet. It actually swims by flipping its tail around,” said Capt. Jim Loper, concepts and innovation department head, Navy Warfare Development Command, Norfolk.
The robot-fish is highly maneuverable and can accelerate quickly, reaching speeds up to 40 knots, Loper said. Being propelled by its tail instead of a shaft or propeller helps it remain stealthy and energy efficient. The shark-like sensor is engineered to carry a range of payloads from acoustic sensors to underwater cameras, he explained.
Built in Massachusetts by a firm called Boston Engineering, the robot fish could be used for a range of missions including undersea mine detection or prolonged surveillance of ships, ports and submarines. “We’re imaging this can loiter for days, possibly weeks on a battery that allows it to maintain its position. This is a sensor we can put out there that matches in with the local life so to speak,” Loper added.
The UUV is currently configured with a lithium ion battery and is engineered so that its front end remains stationary in order to maximize sensor performance. “The fact that the front portion of the animal is mainly stationary when swimming is important because when you carrying sensors, you don’t want everything moving all over the place and messing up what you are carrying on board,” Mark Smithers, vice president and chief technology officer at Boston Engineering, said in a written statement.
Another test of the robot-fish is slated for this coming December, said John Hottendorf, CRIC program manager. “This is an empty truck. You can put whatever kind of sensor you want on it,” Hottendorf said.
Should development continue as expected, the robot-fish could wind up being ready for deployment and operational use within the next several years, Hottendorf explained.
The robot-fish UUV could, at least in theory, work well with another project currently being developed by the CRIC called Suspended Undersea Raw Fiber, or SURF.
SURF involves the use of underwater fiber optic cable used to create secure, seamless point-to-point communications possibilities for surface and undersea entities such as ships, submarines and underwater vehicles.
Navy developers with CRIC have been working closely with laboratory scientists at Penn State who have developed a special kind of buoyant fiber-optic cable.
“They have developed a way to make the fiber cable neutrally buoyant or at least able to suspend itself in the water column. The idea is to take this cable with a high data rate up to 10-gigabytes and be able to connect point to point with zero detectability. The idea is to facilitate low observable communications so you can have high speed communications without worrying about a radio transmission being detected,” Loper said.
Some initial tests of SURF attached to a buoy off of Virginia beach have assessed the ability of the cable to withstand the wind and waves and suspend in the water column above the bottom of the ocean while not floating to the top, Loper explained.
In theory, miles of spooled out underwater fiber-optic cable could connect ships to submarines in real time, allowing them to seamlessly pass combat-relevant sensor data, he added. “In the future when we get this thing going, you could attach a ship and a submarine. The submarine can go several miles out of the way and do what it needs to do with a cable connecting it. All of the surface and air radar from a ship can be going back to a sub. Meanwhile, a sub can be passing all of its acoustic contacts back to the ship,” he said.
The CRIC is working with prototypes of SURF at the moment while exploring ways to further ruggedized the cable for maritime use. “The ocean environment has turned out to be a little more hostile than the original designers imagined. We want to send out 40, 50 or 60 miles of cable,” Loper said.
In addition, the SURF cable could wind up being attached to something like the robot-fish UUV, a scenario which would allow the underwater sensor to send images and data back to a submarine or ship in real time. "You could have a sub with a fish-like UUV tethered onto a cable, giving real time feedback as opposed to current ones that come back for a download. This would be a mechanism for having real-time contact with your UUVs,” Loper explained.
Overall, the robot-fish and SURF are examples of the kind of work explored by Greenert’s CRIC, an entity designed to turn promising technologies around within a year or two for about $1 million to $2 million. The CRIC is configured solely to harvest technological innovation and is not tailored to meet a specific operational threat.
“With the CRIC, we don’t necessarily answer to current fleet needs. The CRIC as an organization is looking for opportunities. We are looking for the thing that is out there now that we don’t know we need yet. What we’re trying to do is repurpose technologies that are out in the commercial world,” Loper said.