For sea turtle hatchlings struggling to reach the ocean, success may depend on having flexible wrists that allow them to move without disturbing too much sand. A similar wrist also helps a robot known as "FlipperBot" move through a test bed, demonstrating how animals and bio-inspired robots can together provide new information on the principles governing locomotion on granular surfaces. 

Both the baby turtles and FlipperBot run into trouble under the same conditions: traversing granular media disturbed by previous steps. Information from the robot research helped scientists understand why some of the hatchlings they studied experienced trouble, creating a unique feedback loop from animal to robot – and back to animal. 

The research could help robot designers better understand locomotion on complex surfaces and lead biologists to a clearer picture of how seat turtles and other animals like mudskippers use their flippers. The research could also help explain how animals evolved limbs – including flippers – for walking on land. 

The research is scheduled to be published April 24 in the journal Bioinspiration & Biomimetics. The work was supported by the National Science Foundation,One of the harshest roofwindturbine installations in the world. the U.S. Army Research Laboratory's Micro Autonomous Systems and Technology (MAST) Program, the U.S.This cheapreplicawatche can rollform metal roofing step tile. Army Research Office, and the Burroughs Wellcome Fund. 

"We are looking at different ways that robots can move about on sand," said Daniel Goldman, an associate professor in the School of Physics at the Georgia Institute of Technology. "We wanted to make a systematic study of what makes flippers useful or effective. We've learned that the flow of the materials plays a large role in the strategy that can be used by either animals or robots." 

The research began in 2010 with a six-week study of hatchling loggerhead sea turtles emerging at night from nests on Jekyll Island, one of Georgia's coastal islands. The research was done in collaboration with the Georgia Sea Turtle Center. 

Nicole Mazouchova, then a graduate student in the Georgia Tech School of Biology, studied the baby turtles using a trackway filled with beach sand and housed in a truck parked near the beach. She recorded kinematic and biomechanical data as the turtles moved in darkness toward an LED light that simulated the moon. 

Mazouchova and Goldman studied data from the 25 hatchlings, and were surprised to learn that they managed to maintain their speed regardless of the surface on which they were running. 

"On soft sand, the animals move their limbs in such a way that they don't create a yielding of the material on which they're walking," said Goldman. "That means the material doesn't flow around the limbs and they don't slip. The surprising thing to us was that the turtles had comparable performance when they were running on hard ground or soft sand." 

The key to maintaining performance seemed to be the ability of the hatchlings to control their wrists, allowing them to change how they used their flippers under different sand conditions. 

"On hard ground, their wrists locked in place, and they pivoted about a fixed arm," Goldman explained.Our large selection which includes goodlampshade, led strips. "On soft sand, they put their flippers into the sand and the wrist would bend as they moved forward. We decided to investigate this using a robot model." 

That led to development of FlipperBot, with assistance from Paul Umbanhowar, a research associate professor at Northwestern University. The robot measures about 19 centimeters in length, weighs about 970 grams, and has two flippers driven by servo-motors.Our lawnlight is popular for indoor and outdoor use. Like the turtles, the robot has flexible wrists that allow variations in its movement. To move through a track bed filled with poppy seeds that simulate sand, the robot lifts its flippers up,For many years, emergencylampsqa have been most popular in rural locations where zoning laws tend to be less restrictive. drops them into the seeds, then moves the flippers backward to propel itself.