The Pentagon's research arm has backed the development of the Nano Hummingbird, an experimental miniature drone that could one day do reconnaissance by landing on a window ledge.
The pocket-size drone, developed by AeroVironment as a mini-spy plane capable of manoeuvering on the battlefield and in urban areas, flaps tiny robotic wings.
The battery-powered drone was built over five years for the Pentagon's research arm as part of
a series of experiments in nanotechnology.The little flying machine is built to look like a bird for potential use in spy missions.
Equipped with a camera, the drone can fly at speeds of up to 17km/h, AeroVironment said. It can hover and fly sideways, backwards and forwards, as well as go clockwise and counterclockwise, by remote control for about eight minutes.
The quick flight meets the goals set forth by the government to build a flying "hummingbird-like" aircraft.
It also demonstrates the promise of fielding mini-spy planes.
Industry insiders see the technology eventually being capable of flying through open windows or sitting on power lines, capturing audio and video while enemies would be none the wiser.
The Hummingbird would be a major departure from existing drones that closely resemble traditional aircraft.
The next step is likely to be further refinement of the technology, officials said, before decisions are made about whether the drones would be mass-produced and deployed.
"The miniaturisation of drones is where it really gets interesting," said defence expert Peter W. Singer, author of Wired for War, a book about robotic warfare.
"You can use these things anywhere, put them any place, and the target will never even know they're being watched."
The mini-drone weighs 19 grams, or less than an AA battery. The Hummingbird's innards are made up of motors, communications systems and a video camera. It is slightly larger than the average hummingbird.
The success of the program "paves the way for a new generation of aircraft with the agility and appearance of small birds", Todd Hylton, Hummingbird program manager for the Pentagon's research arm, said in a statement.
In all, the Pentagon has awarded about $4 million to AeroVironment since 2006 to develop the technology and the drone itself.
Matt Keennon, the company's manager on the project, said it was a technical challenge to create the mini-machine from scratch because it pushed the limitations of aerodynamics.
Less than two years ago, an earlier version of the drone could fly for 20 seconds. Keennon said the current eight minutes of flight were likely to be extended as experiments continued.
"This is a new form of man-made flight," Keennon said. It is about "biomimicry", or building a machine that is inspired by nature, he said.
The Pentagon issued seven specific milestones for the Hummingbird, including the ability to hover in an 8km/h wind gust and the ability to fly from outdoors to indoors and back outdoors through a normal-size doorway.
Critics have noted that privacy issues might emerge depending on how the drones are used.
For now, the Hummingbird is just a prototype, Keennon said. But 10 years from now, he sees the technology carrying out detailed reconnaissance missions.
But it's not likely to resemble a hummingbird, considering that that's a rare bird in, say, New York City.
"I'm not a bird expert, but a sparrow seems to be better," Keennon said.
