UA professor says snakes are key to better-moving robots

words and photos by Skylar Cole

Penny is a Vietnamese beauty snake. She is the lab mascot for Dr. Henry Astley, an assistant professor in the Biology Department and Department of Polymer Science at the University of Akron who studies the locomotion of animals and, most recently, the physics of underwater locomotion, specifically in animals like salamanders or newts.

Astley got Penny because he didn’t feel right having lab animals specific for testing, and there was too much protocol to bring in his own snakes from home, so Astley adopted Penny as a lab mascot that he can also use in his research. As I walked into this interview, Penny was handed to me and happily slithered around me for the hour-long conversation.

There are 3,700 species of snakes. For comparison, there are about 6,000 species of mammals, but 1,200 of those are bats and another 1,000 are rodents. Snakes alone are coming close to edging out non-flying mammals. In a rough back-of-the-envelope calculation, Astley calculated that “among tetrapods, which is the group that contains all vertebrates that aren’t fish, basically, limbless locomotors are roughly 12% of all species.”  

But if the quantity of snakes in our world is so large, why are they so under-researched? 

“They are perceived as weird and aberrant and sort of a niche,” Astley says. “We think everything walks and flies and swims, so why are you wasting time studying limbless organisms?”

Penny has roughly 200 body vertebrae and another hundred or so in her tail. In the body vertebrae, every bone has a pair of ribs and every rib has 20 or more muscles, which can span to as many as 50 segments of her body, repeated all the way down. Astley says Penny has “as many as 8,000 muscles in her body,” while humans have around 650.

Astley’s research is being used to create robots as a part of UA’s biomimicry program, which works to find nature-inspired solutions to tackle complex human problems. In particular, a snake-inspired robot would be useful in unpredictable terrain. 

“Snakes move better in complex, cluttered, and confined terrain when there is something to create friction against. So if you were to set Penny on this floor, she would just sort of flail around to go almost nowhere… [but] in dense grass or rubble, she would be able to push off of the objects around her and fly.” 

A study conducted in the early 1990s showed that snakes move faster and faster as they encounter more obstacles, in the same places where wheels would slow down. Astley explains that in situations such as earthquakes and collapsed buildings, you want to find people as fast as possible. Snake-like robots would be one way to do it. They could better maneuver and push off of their surroundings to find survivors faster and more efficiently than traditional methods. On Mars, he stated, a snake robot would be better equipped to maneuver the dusty, rocky terrain. 

Astley wants people to understand just how amazing–and accessible– snake locomotion is. We encounter snakes every day and we just don’t know it — they could be hiding under a log, in the grass, in water, or even in the dirt. He made the point that humans spend millions of dollars on research to create robots without looking at the simple things around us first for inspiration. Astley says he wants to take snake locomotion out of the niche it’s in so more people can appreciate and understand it.

Recently, Astley was awarded the $297,267 two-year EAGER (Early Concept Grants for Exploratory Research) grant from the National Science Foundation to research the physics of underwater locomotion using newts. 

Skylar Cole is a senior at Bio-Med Science Academy.