Two African penguins stretch their flippers at the Maryland Zoo.
At the American Physical Society's fluid dynamics conference this winter, there was a healthy infusion of biology. In between talks on propellers and plane wings, there were presentations about flying snakes, fire ants, humpback whales and hummingbirds. Physicists from all over the world are turning to the natural world to help them solve engineering problems.
It's not a new phenomenon. Otto Lilienthal, the "Father of Flight," famously studied storks to help him develop his gliders. But it's still a bit surprising that another scientist has turned to flightless birds for inspiration — specifically, he's turned to African penguins.
Flavio Noca, now a professor of aerodynamics at Switzerland's University of Applied Sciences, first encountered the power of penguins back when he was a grad student. He came across a paper that described the incredible acceleration of emperor penguins: from zero to 15 mph in just a second.
"I was just amazed by their performance," Noca remembers. "That's when, basically, I decided, 'OK, I want to work on penguins.' "
It's not just their speed that impressed him. Penguins can move side to side and make sharp turns effortlessly — things that underwater craft built by humans struggle to do. But very few people have studied penguins, so little is known about how these champion swimmers manage their underwater acrobatics.
"There are just, for some reason, only two basic papers," Noca says.
So Noca set out to learn more. He started by filming zoo penguins to track the exact movement of their wings.
"It was very hard because penguins have their own mind[s] so they're not going to go where you want them to go," Noca says.
But after analyzing lots of underwater videos, Noca and his students were able to describe the exact stroke of a penguin's flipper. But they still needed a way to model that movement in the controlled lab environment.
This year, Noca's research assistant, Bassem Sudki, developed and manufactured a completely novel joint mechanism that can mimic the stroke of a flipper. With the mechanical flipper churning in the water, Noca can better measure the flows and forces involved, and learn exactly how penguins achieve their maneuverability. He says someday this mechanism could help underwater craft dart through oceans.
The flipper mechanism is just one example of the bio-inspired design on display at this year's fluid dynamics conference. Many of the attendees believe they are on the edge of a new wave of discovery. Scientists finally have the technology not only to understand mechanics in the natural world, but also to actually replicate natural structures within human-made machines.
Nature, they say, can help engineers when they are stuck on a particular problem.
"Nature has been going through millions of years of engineering," Noca explains. "And it has found one solution."
It might not be the best solution, but it could be one that humans are able to imitate and improve upon.