How Darpa's Tiny Robotic Hummingbird Hovers and Films | Popular Science

How Darpa's Tiny Robotic Hummingbird Hovers and Films | Popular Science: "AeroVironment has a working prototype: the 6.5-inch-wingspan Nano Hummingbird. “It was never our intention to copy what nature has done; it’s just too daunting,” says Matt Keennon, the UAV’s head researcher. The camera-equipped bird beats its wings 20 times a second, whereas hummingbirds clock up to 80. Still, it can hover like the real thing, plus perform rolls and even backflips. Here’s how the bird flies."