Resembling a feathered flying ace with his miniature protective goggles and chinstrap, a parrotlet named Obie stood ready to take off. On signal, Obie propelled into the air, flapped through a laser field infused with microparticles and landed on another perch three feet away.
The journey only lasted three seconds, but it challenged the accuracy of three aerodynamics models long used to predict animal flight. It also might impact future designs of bio-inspired drones, robots and unmanned aerial vehicles, a topic of interest to the Navy and Marine Corps.
Sponsored by the Office of Naval Research, researchers at California’s Stanford University found a new way to precisely measure the vortices -- patterns of rotating air -- created by birds’ wings during flight. The results shed greater light on how these creatures produce enough lift to fly.
“One of the most exciting recent advances in understanding flying animals has been the use of new technologies like this to collect all kinds of data in free-flight conditions,” said Marc Steinberg, the ONR program manager overseeing the research. “We can learn what’s really happening -- the biology and physics -- and apply it to create UAVs capable of navigating challenging environments like under a thick forest canopy or through urban canyons.”
Led by David Lentink, an assistant professor of mechanical engineering, the Stanford team tested three models commonly used to estimate how much lift birds and other flying animals generate when flying.