Coming, aerial robots modelled after flying snakes
Posted on Feb 01 2014 | IANS
New York, Jan 31 : A flying snake is not a fairytale creature. Some snakes really do sail through the air and look like unidentified flying objects (UFOs).
The researchers are hopeful that understanding such snakes' flight pattern can help them make tiny aerial robots - to be used in search and rescue missions in places where humans or larger devices could not enter.
Snakes in the genus 'Chrysopelea' can remain airborne for up to 100 feet in rainforest habitats in southeast Asia.
The snakes launch from a tree, flexing their ribs as they initiate a glide.
They then stretch and flatten their bodies from a circle into an arched semi-circle.
"It looks like someone's version of a UFO," study co-author Jake Socha of Virginia Tech's College of Engineering in the US was quoted as saying in a press release.
Socha and his colleagues first watched the snakes in action.
The researchers used a 3-D printer to produce a rod with the same cross-section as the snake's body.
They then placed it across a tank filled with water that flowed over the snake-shaped bar.
They flowed water over the model at a specific range of speeds. Those speeds ranged from about 8 to 20 inches per second.
Slightly tilting the snake model revealed that, at most angles, the snake's body generated sufficient lift to account for the impressive gliding.
When the rod was flat, however, turbulence created a suction-like force on the snake model, pulling it downward.
The model, however, does not fully explain how snakes use their long bodies to stay airborne for so long.
"If you make a rough estimate of the lift to drag ratio for the real animal, it appears to do better than what we got from this study," Socha said in the study published in the Journal of Experimental Biology.