Its creators, from the Georgia Institute of Technology (Georgia Tech) and Northwestern University, wanted a better understanding of how these animals use their flippers and fins to move on surfaces like sand.
Flipperbot, which is 19 centimeters long and weighs 790 grams, crawls by using two flipper-like front limbs that span about 40 centimeters. To power the turtle-like robot, each of its limbs is equipped with small servo motors with thin, lightweight flippers attached to the end.
Flipperbot could also help scientists gain a better understanding of how structures like fins and flippers evolved when fish-like animals moved from the water onto land several hundred million years ago.
To better understand the mechanics of flipper-based movement on land Daniel Goldman from the Georgia Tech team said that his group, before designing Flipperbot, to better understand the mechanics of flipper-based movement on land, researchers studied how hatchling sea turtles propelled themselves from their nests on sandy beaches into the sea.
“Flipperbot allowed us to explore aspects of the sea turtle’s gait and structure that were challenging, if not impossible, to investigate in field experiments using actual animals,” said Goldman.
The researchers realized the advantages of a free moving wrist, instead of a fixed wrist, at the end of the flipper. When fitted with a free wrist, Flipperbot moved much more effectively over the ground while not disturbing much surface material as it propelled itself forward.
“With a fixed wrist, the robot also interacts with the ground that has already been disturbed by its previous steps, which hinders its movement,” Goldman said.
Video of “Flipperbot” in action (Institute of Physics)
The researchers tested Flipperbot on a 122-centimeter-long bed of poppy seeds and recorded its movements with a high-speed digital camera.
The study’s co-author, Nicole Mazouchova, also from Georgia Tech, believes further robot testing could help in turtle conservation biology.
“The natural beach habitat of hatchling sea turtles is endangered by human activity,” she said. “Robot modeling can provide us with a tool to test environmental characteristics of the beach and implement efforts for conservation.”