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Five years ago, NASA’s rover on Mars, Spirit, got stuck in sand while exploring the red planet. Recently, another NASA vehicle on Mars, Curiosity, had to change its path to avoid a sandy area. Scientists realized they needed to find a way to prevent the costly robots from getting trapped in the sand. So, they looked to nature for answers. The researchers brought deadly snakes to a zoo in Atlanta, Georgia. The sidewinder rattlesnakes are native to the southwestern United States. The researchers put the creatures in a box of sand. The scientists video recorded the snakes as they moved sideways up different sand hills. Their movement is called sidewinding. Daniel Goldman teaches physics at the Georgia Institute of Technology in Atlanta. He says the snakes moved easily in the sand even when the sand was moving. Mr. Goldman and other researchers wrote about their findings in the journal Science. The researchers then performed experiments with a robotic snake developed at Carnegie Mellon University in Pittsburgh, Pennsylvania. MOD-Snake is one meter long, and has 16 parts, or modules. Each part is 6 centimeters wide. The robot is known for its ability to get in and out of tight spaces. MOD-Snake helped show why sidewinders climb better than other snakes. Now the researchers are working on the next generation of Mod-Snake. They hope this sidewinder version will travel through sand well as real snakes. The robot might be able to explore Earth or other planets. It also might be useful in rescue operations.
