Scientists at Stanford University have trained a Parrotlet called Obi to wear some pretty rad goggles and fly through laser sheets in an effort to test models that predict the lift generated by flying animals. The purpose of this experiment is to help develop better flying robots in the future. Obi wears those cool goggles to protect his bird eyes from the laser beams he is flying through.
The scientists infused the air Obi flies through with tiny aerosol particles that are primed to scatter and track disruptions in the air. Obi is trained to fly from one platform to another when the researcher points. The goal of the experiment is to precisely measure the vortices that Obi creates in flight.
Researchers want to explain how animals generate enough lift to fly. “The goal of our study was to compare very commonly used models in the literature to figure out how much lift a bird, or other flying animal, generates based off its wake,” said Diana Chin, a graduate student in the Lentink lab and co-author of the study. “What we found was that all three models we tried out were very inaccurate because they make assumptions that aren’t necessarily true.”
The goggles Obi wears have reflective markers on the sides to allow measurement of velocity. When Obi flies through the laser sheet and the aerosol particles scientists were able to gain the clearest picture to date of the wake left by a flying bird. Previous measurements thought that the vortices generated by the bird’s flight would remain relatively frozen over time similar to how airplane contrails remain. However, the team found that the bird generated vortices break up suddenly. The team found that all-new models are needed for bird flight.
“Many people look at the results in the animal flight literature for understanding how robotic wings could be designed better,” said Stanford mechanical engineer David Lentink. “Now, we’ve shown that the equations that people have used are not as reliable as the community hoped they were. We need new studies, new methods to really inform this design process much more reliably.”