The Stealthy Little Drones that Fly Like Insects
Phoenix666 writes:
BBC:
Known as Skeeter, the secretive project has cracked the challenge of using flapping wings to power a drone. While wings are more efficient than a propeller and allow a dragonfly to hover in the face of strong gusts they are almost impossible for human engineers to emulate.
"Making devices with flapping wings is very, very hard" says Mr Caccia. Helicopters manoeuvre by changing the pitch of rotor blades to go forward and backward or to hover. For smaller objects hovering is a major challenge.
"A dragonfly is an awesome flyer" says Alex Caccia, "It's just insane how beautiful they are, nothing is left to chance in that design. It has very sophisticated flight control."
The dragonfly does have 300 million years of evolution on its side. Animal Dynamics has spent four years writing software that operates the hand-launched drone like an insect and allows it to hover in gusts of more than 20 knots (23mph or 37km/h). From 22 to 27 knots is classed as a "strong breeze".
[...] It is currently around eight inches long, but production versions are planned to be smaller. Squeezing a lot of aerodynamic and navigational wisdom into a diminutive package is nature's prerogative but was a big challenge for Animal Dynamics. "We started small to learn hard lessons" as Alex Caccia puts it.
[...] Under the family name of DelFly, the creation from TU Delft weighs less than 50g, and takes inspiration from the wing movement of fruit flies. DelFly's four wings consist of an ultra-light transparent foil powered by a light, economical motor, which lets it fly for six to nine minutes.
The project worked beautifully until "due to a terrible miscalculation of scale the entire battle fleet was accidentally swallowed by a small dog."
Read more of this story at SoylentNews.