Robot Reveals Dragonfly Flight

Are four wings better than two? After all the dragonfly has been slicing, and then breaking into a hover, then slicing again (sometimes backward) with quadruple force for 300 million years. Previous studies have said no, that air motion between the pair of fore and hind wings reduces lift.

But research from UK's Royal Veterinary College and the University of Ulm have shown otherwise. Using a robot that simulates dragonfly flight, they found that although flying with two pairs of wings does not offer any advantages for lift, it can improve aerodynamics. When the fore and hind wings are phased just right, the lower wings recover energy from the wing tips that would otherwise swirl away in the waste of a wake.

Dragonflies don't have to be told what makes their flight aerodynamic. But what scientists learn from these agile insects could be one day applied to micro air vehicles.

The paper is here. And you can see video of the robot here.