When was the last time you heard about a sea turtle getting stuck in a shipwreck? Never, that's when. Although that's partly because stuck turtles rarely make the news, it's also due to the fact that they're relatively small and highly maneuverable. With that in mind, the European Union-funded ARROWS project has created U-CAT – a prototype robotic sunken-ship-exploring sea turtle.
Just like a real turtle, U-CAT has four independently-driven flippers that allow it to move up and down, forward and backward, and to pivot on the spot. Propellers would let it do those same things, although they'd also churn up much more visibility-limiting silt in the process.
U-CAT is autonomous, so it doesn't require a control cable that could get snagged or tangled. It also has an onboard video camera, which records video that can later be used to visually map out the inside of the shipwreck.
Plans call for the technology to be tested at underwater archeological sites in the Mediterranean Sea and the Baltic Sea. The idea is that U-CATs could ultimately be used in conjunction with other underwater robots that are too large to enter wrecks, and too expensive to risk losing within them.
Once they get into regular service, U-CATs might not be the only robotic turtles in the sea. Scientists from the ETH Zurich research group are developing a roboturtle of their own, known as naro-tartaruga.
The U-CAT prototype can be seen in action in the video below. If you're interested in seeing it first-hand, its public premier will be taking place this weekend at the London Science Museum's Robot Safari exhibit.
Sources: Tallinn University of Technology, ARROWS Project
[See our article on the BIOSwimmer at http://www.gizmag.com/bioswimmer-robotic-tuna/24213/ - Ed.]
Sadly no mention of it's depth rating and would also be interested in it's buoyancy control if it has any. Where is some video footage from the Turtle's camera? It didn't look as if it could hold a steady video shot flipping and flapping all over the place. A lot of the video would be at only a glance, not impossible, but not so great if you wish to closely study an items condition, position, etc. If it had both small propellers and the fins controlled off the same arms, plus a way to control buoyancy (like a sub) you could use the fins for most situations and the props to hold a steady position where low silting allows it.
I really like the concept and wish all the best, but I suspect the big challenge is in autonomous navigation. The hazards in a wreck- fishing nets, bad visibility, sometimes strong currents, silt are a challenge even to human divers. Understanding the broken form of a shipwreck, recognizing how it relates to the ship when it was new ("oh, this must be the remains of the main deck!"), deciding where to enter. Even worse getting inside- the ship is broken down, full of silt and trash, may be tilted or upside down, with holes in the hull..
But taking it step by step, and solving little tasks first (like "go down with the diver, penetrate hull 10m and return") .. it can take you forward. Just suggest to have some practitioneers in the team..