Toss a paper airplane into a strong wind and it either nosedives or unfolds and blows away. Fly a drone into a strong wind and it struggles to stay stable before crashing into a wall or the ground. Release a flock of birds into a strong wind and it’s poetry in motion. Why can’t we build drones to do that?
It’s just something we haven’t accomplished in robotics yet. We need to study birds up close so we can figure out what their secret is to flying so stably under such difficult conditions, and apply that to aerial robotic design.
Stanford University Professor David Lentink, a biologist and engineer, is well on the way to accomplishing it after developing the world’s first wind tunnel for studying birds in flight. Designed with the help of the US Air Force, the miniature wind tunnel is two meters (6.5 feet) long and has a fan the size of a small car that’s capable of generating winds of up to 180 km per hour (112 miles per hour). A turbulence generating system varies the wind direction and speed and high-speed cameras and motion capture devices record the movements and wing-beats of the birds in milliseconds.
This sounds like it could end up with birds splattered against the back wall but Lentink assures that he’s gentle with the lovebirds, parrotlets and hummingbirds he’s used for his initial tests and has trained them to fly safely in the wind tunnel. As he gets additional birds accustomed to this birdie treadmill, he hopes to have more than one flying at a time to see how wing-flapping in close formation affects other birds and how the birds manage to fly without collisions. He also plans to add fluoroscopes to help see the birds’ muscular-skeletal movements.
Of course, the main goal is to develop drones that can fly in turbulence like birds, possibly even developing wings that extend or retract in response to wind conditions. If he can accomplish this with his bird wind tunnel, Lentink puts himself in a pretty exclusive group:
Ever since Otto Lilienthal and the Wright Brothers studied birds to invent their airplanes, engineers have relied on talking with biologists to learn the tricks birds use.
Otto Lilienthal? He was the German aviation pioneer whose inventions earned him the name Glider King. What will Lentink’s nickname be? Wind-tunnel Wizard? Duke of Drones? Bird Baron?