Bird Wind Tunnel Built for Better Drone Flight
Lovebirds, parrotlets, and hummingbirds are trained with positive reinforcement methods, similar to how dogs are trained to perform tricks.
Drones have a long way to go before they'll ever mimic the graceful maneuverability of birds. But a new wind tunnel at Stanford University is allowing researchers to study the nuances of bird flight to build better drones.
"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," said David Lentink, assistant professor of mechanical engineering at Stanford University.
The wind tunnel is a narrow, rectangular room with a fan about the size of a Volkswagen Beetle. An observation section about two meters long has windows on six sides too allow high-speed cameras and motion-capture devices to record data.
The fan producing the wind is highly tunable and can create wind speeds up to 50 meters per second, as well as a range of turbulent conditions.
Wind speeds of seven meters per second are generally used for a standard tests with the birds and the higher speeds are reserved for analyzing drone flight - not birds.
Lovebirds, parrotlets, and hummingbirds take part in the tests and are trained with positive reinforcement methods, similar to how dogs are trained to perform tricks. Birds get treats when they accomplish a desired task.
Data from the wing motions recorded inside the wind tunnel help the researchers understand the forces that flying put on the wings as well as on the surrounding air.
After training several birds, Lentink and his team plan to test entire flocks in the tunnel to see how wind and turbulence affect groups flying close together.
Lentink hopes to introduce other instruments into mix later this summer, including two fluoroscopes, which will allow his team to visualize the muscular-skeletal movements made during flight.
The analysis will eventually help them build drones and drone swarms that can fly without issues at any altitude and in close proximity. Lentink envisions entirely new drone designs to come out of this research, such as winged robots that morph their wing shape in order to maintain stability.
See the video below for more details.