Researchers have created a robot that mimics how baby sea turtles scuttle across the sand to reach the ocean just after hatching. Dubbed "Flipperbot," the scientists hope that the insights they gain from understanding the physics of sea turtle locomotion on land could lead to better ways to protect beaches and the endangered marine mammals that call it home.
They also hope it may provide clues to the movement of other critters that used their flippers to draw themselves from ocean to land -- like the mudskipper, sea lion or an ancient lobe-finned animal called the Tiktaalik.
"Flipperbot" was built by a team of physicists and engineers at Georgia Tech and Northwestern University. The idea came after looking at the results of an earlier study of how baby loggerhead sea turtles walk across the sands of Jekyll Island, Ga., just after hatching, said Daniel Goldman, a professor of physics at Georgia Tech.
"In that study we noticed they were doing a bend at their wrists," Goldman said. "We made some speculation, but didn't have any solid evidence. So we built a turtle inspired robot that functions as a physical model." (See a video of the device.)
Goldman said that not all baby sea turtles are good at scampering across the beach. Some were able to propel themselves pretty well, others dug themselves into a hole.
"There are those who move well and those who move poorly," Goldman said. "The difference is fairly small. Small changes in how sand leads to large effects. This is important because these animals are under severe predation on the beach, everything wants to eat them when they pop out of the nest."
The team use the photos and videos from Jekyll Island hatchlings to build Flipperbot in the lab. The resulting device propels itself over a bed of poppy seeds, which have similar physical characteristics as sand without the problem of moisture, according to Paul Umbanhowar, a physicist and mechanical engineer at Northwestern University.
Umbanhowar said understanding beach surfaces and how turtles move is important because many beaches in the United States are often subject to beach nourishment programs, where sand is dredged and dumped to prevent erosion.
"If you are restoring a beach, it might be the wrong kind of sand or deposited in a way that is unnatural," Umbanhoward said. "In order for this turtle to advance, it has to generate these kind of thrust forces and it may be unable to get their flippers into it. We could say something about that given our models."
Conservationist Serge Dedina is intrigued by Flipperbot. He says sometimes advances in understanding how the animals move and live is important to protecting them. Dedina has worked to protect marine turtles in the United States and Mexico from human and natural predators, and says he's seen the impact of increased hurricane activity on beaches that are important breeding grounds for sea turtles.
"With a Flipperbot, you could send those things out to determine what the impacts have been for erosion," said Dedina, executive director of Wildcoast, a binational marine conservation group based in Imperial Beach, Calif. "Small, smart things can make a big difference for marine animals."
The Georgia Tech study appears today in the journal Bioinspiration and Biomimetics.