However, researchers at the Georgia Institute of Technology recently created a real-life, snake-like robot capable of swimming through granular material. While their serpentine robot may look like creature from a mystical desert planet, their inspiration is anything but science fiction.
Modeled after the sandfish lizard that escapes predators by diving beneath the sand's surface, the Georgia Tech team hopes that, by studying their robot, a future version potentially could be used to burrow through debris to rescue earthquake victims.
"One of the challenges for robots that must operate in complex shifting environments, like those found in land slides and disaster sites is that we don't have a deep understanding of the principles by which matter interacts with such environments," said Daniel Goldman in video released by the university. Goldman is an assistant professor in the School of Physics at Georgia Tech and part of the team working on the robot.
The snake-like robot is constructed of seven connected segments, each powered by a servo motor. Segments are encased in a latex sock and then wrapped in spandex, providing a smooth skin for undulating through the "granular medium," a euphemism for quarter-inch plastic balls.
More important than the robot's swimsuit was a feature that required some experimentation.
"Biologists have argued and speculated that the head shape of this animal allows the animal to move in the sand well," said Goldman. "The predominate idea is that the head is basically kind of a wedge shape that reduces drag as the animal moves through the medium."
When the team experimented with a robot head that angled 155 degrees, the robot swam down through the plastic balls. Raising the tip of the head from 0 to 7 degrees, the robot's downward trajectory decreased until it became level. When the tip was pointed above 7 degrees, the submerged robot swam back to the surface.
The team currently plans on testing their robot in material similar to debris found at disaster sights.
Photo: Courtesy Georgia Tech