INSPIRING ROBOTS

Biologically inspired robotics has developed into a major focus at the Institute, with multiple labs looking to the animal kingdom for inspiration. One challenge that has long vexed researchers is the ability to traverse across sand. It’s a tricky prospect, as sandy surfaces can take on the properties of a solid, a liquid and even a gas.

But while robots struggle with the surface, various animals are able to move across sand, including lizards, sea turtles and snakes. Now Tech roboticists are mining the creatures’ behavior for their evolutionarily perfected secrets.

Animals are inspiring Tech’s faculty and students to create advanced robots, medical technology and improved prosthetics, among other developments that will shape the future, both saving and improving human lives.

A robotics team led by Dan Goldman, an associate professor in the School of Physics, and David Hu, an associate professor of mechanical engineering, began performing comparative studies on how sea turtles and sandfish (which essentially swim on land) move over sand.

Then they turned to snakes.

One snake-based robot that came out of the lab—known as Scalybot—was effective on many surfaces, but it always got stuck in sand. Many real snakes struggle with sand, too.

They partnered with Joe Mendelson, curator of herpetology at Zoo Atlanta and an adjunct professor at Tech, to study a snake that’s at ease on sand: the sidewinder rattlesnake.

“They’re famous for their funky sideways locomotion through sand dunes,” Mendelson says.

Georgia Tech prohibits venomous snakes on campus, and Tech researchers themselves can’t handle poisonous animals. Mendelson’s position at Zoo Atlanta allowed him to collect sidewinders from Arizona and conduct the research at the zoo in “the world’s most expensive sandbox.” Tech’s researchers simply observed the results.

The team now has a firm understanding of how sidewinders handle sandy slopes, and they’re examining how the snakes navigate obstructions. While sidewinder-style robots have obvious uses—search-and-rescue missions, military operations, planetary exploration—research partners from Harvard University have suggested sending the robots into sand-filled tunnels in Egyptian ruins.

“A robot can’t go down a sand-choked tunnel underground—only a snake can do that,” Mendelson says. “So we need a sidewinding robot with a camera that can look around. Then [if something of value is down there] you can put in the effort to dig it out.”

The needs of robots extend far beyond traversing sand, and inspiration has come from some surprising places. Hu received a lot of attention in 2012 for publishing a study of the “wet-dog shake”—when dogs shake wildly to dry themselves.

The physics of the wet-dog shake are impressive—dogs can shake themselves 70 percent dry in just a fraction of a second. While the research might seem silly, it does have useful implications. Hu says the research could be used for improved drying technology or in robotics.

“In the future, self-cleaning and self-drying may arise as an important capability for cameras and other equipment subject to wet or dusty conditions,” he says.

 

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IMPROVING HUMAN LIVES

The School of Applied Physiology is home to the Comparative Neuromechanics Lab, where humans, rats and other creatures run on instrumented treadmills. Meanwhile, researchers gather data on how animals move.

This comparative data reveals a wealth of information on how healthy animals move, and how their bodies compensate after an injury. The findings are critical to the development of new approaches to rehabilitation of human and animal patients.

This research could be a potential alternative to bone-grafting operations.

The lab’s director, associate professor Young-Hui Chang, says he’d wanted to study animal locomotion ever since growing up watching animals in National Geographic documentaries.

The lab’s data also is being used in Tech’s Center for Prosthetic and Orthotic Research and Education to design and test new prosthetics, which are changing the lives of humans with missing limbs.

In the biotech quad on campus, the Parker H. Petit Institute for Bioengineering and Biosciences is focused largely on studying disease and injury and developing innovative treatments. One recent study showed that delivering stem cells on a polymer scaffold to treat large areas of missing bone led to improved results compared to using a scaffold alone. This research—conducted on rats—could be a potential alternative to bone-grafting operations.

“Massive bone injuries are among the most challenging problems that orthopedic surgeons face, and they are commonly seen as a result of accidents as well as in soldiers returning from war,” says the study’s lead author, Robert Guldberg, a professor of mechanical engineering and the Institute’s executive director. “This study shows that there is promise in treating these injuries by delivering stem cells to the injury site. These are injuries that would not heal without significant medical intervention.”