Washington (AFP)
Since the beginnings of aviation, the inventors have been brainstorming to create machines that fly as nimbly, quickly and gracefully as birds.
This dream got a little closer to reality on Thursday. Researchers at Stanford University have announced that they have carefully studied the wings of dead pigeons to create the "PigeonBot", a kind of drone with wings made of 40 real feathers.
"Aerospace and materials engineers can now begin to rethink how to design and make wings and materials that transform as skillfully as birds do," said David Lentink, a professor of mechanical engineering at Stanford and author of two articles. describing the results of this study in Science and Science Robotics.
All four-membered animals, including dinosaurs, come from an ancestor who had five fingers at the end of his limbs, which over time became hands, paws, fins or wings.
Today's birds, like pigeons, have kept three fingers. When studying their wings in a wind tunnel, the researchers noticed that their wrists and fingers made it possible to precisely control the position of their feathers and the wingspan of their wings.
During flight tests, the manipulation of the wrist and fingers triggered tight and precise turns, evidence according to the researchers that birds mainly use these fingers to navigate in flight.
The teams also discovered how the birds adapt their wings in flight: the adjacent feathers can stick together with a micro-structure functioning like Velcro to make the journey more fluid.
These feathers cling to each other when the wing expands and detach again when it contracts, making it more resistant to turbulence.
Researchers have noticed that similar structures exist in many bird species, except for owls, which can thus fly more quietly.
These Velcro-like structures, known as "lobate cilia" could have a wide range of uses, from medical to aerospace, which represents for Mr. Lentink and his colleagues many sources of inspiration for future research.
© 2020 AFP