Scombrid fishes like Tuna are high-performance swimmers, especially during behaviors such as escaping from predators or catching prey. A robot inspired from ‘tuna’ can wriggle just as fast as real fish and swim faster than most other robots of its type. This “Tunabot” could help us learn how fish use their fins and may someday be used for underwater surveillance.
Hilary Bart-Smith and her colleagues at the University of Virginia built a Tunabot from 3D-printed steel and resin, covered in a stretchy plastic skin. It is designed to mimic an adolescent tuna, but without any fins other than the tail, and is about 25 centimetres long.
To explore the high-frequency fish swimming performance space, they designed and tested a new platform based on yellowfin tuna (Thunnus albacares) and Atlantic mackerel (Scomber scombrus). They swim by wiggling their whole bodies back and forth up to about 10 times per second – the faster they thrash, the faster they swim.
The ‘Tunabot’ can wiggle back and forth up to 15 times per second and swim at about 1 meter per second, not quite as fast as tuna but far faster than most other swimming robots. Making Tunabot more similar to actual tuna could help us learn how the tuna themselves swim, says Bart-Smith.
Bart-Smith and her team are working to develop Tunabot as a swimming surveillance robot, both to monitor things like the structural integrity of ship hulls and bridge supports and possibly to keep an eye out for more nefarious goings-on underwater.
The Tunabot has a range of ~9.1 kilometers if it swims at 0.4 meter per second or ~4.2 kilometers at 1.0 meter per second, assuming a 10–watt-hour battery pack. These results highlight the capabilities of high-frequency biological swimming and lay the foundation to explore a fish-like performance space for bio-inspired underwater vehicles.
you can find complete paper here: https://robotics.sciencemag.org/content/4/34/eaax4615