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Scientists are abuzz with talk and work on robotic spy bugs

A mechanical fly with a wingspan of less than an inch and weighing less than a gram is being developed by the Harvard Microrobotics Lab. Its wings buzz at 120 beats per second. A mechanical fly with a wingspan of less than an inch and weighing less than a gram is being developed by the Harvard Microrobotics Lab. Its wings buzz at 120 beats per second. (Robert Wood/Harvard University)

WASHINGTON - Vanessa Alarcon saw them while working at an antiwar rally in Lafayette Square last month.

"I heard someone say, 'Oh my god, look at those,' " the college senior from New York recalled. "I look up and I'm like, 'What the hell is that?' They looked kind of like dragonflies or little helicopters. But I mean, those are not insects."

Out in the crowd, Bernard Crane saw them, too.

"I'd never seen anything like it in my life," the Washington lawyer said. "They were large for dragonflies. I thought, 'Is that mechanical, or is that alive?' "

That is just one of the questions hovering over a handful of similar sightings at political events in Washington and New York. Some suspect the insectlike drones are high-tech surveillance tools, perhaps deployed by the Department of Homeland Security.

Others think they are, well, dragonflies - an ancient order of insects that even biologists concede look about as robotic as a living creature can look.

No agency admits to having deployed insect-size spy drones. But a number of US government and private entities acknowledge they are trying.

The robobugs could follow suspects, guide missiles to targets, or navigate the crannies of collapsed buildings to find survivors.

The technical challenges of creating robotic insects are daunting, and most specialists doubt that fully working models exist.

"If you find something, let me know," said Gary Anderson of the Defense Department's Rapid Reaction Technology Office.

But the CIA secretly developed a simple dragonfly snooper as long ago as the 1970s. And given recent advances, even skeptics say there is always a chance that some agency has quietly managed to make something operational.

"America can be pretty sneaky," said Tom Ehrhard, a retired Air Force colonel and specialist in unmanned aerial vehicles who is now at the Center for Strategic and Budgetary Assessments, a nonprofit research institute in Washington.

Robotic fliers have been used by the military since World War II, but in the past decade their numbers and level of sophistication have increased enormously. Defense Department documents describe nearly 100 different models in use today, some as tiny as birds, and some the size of small planes.

But getting from bird size to bug size is not a simple matter.

"You can't make a conventional robot of metal and ball bearings and just shrink the design down," said Ronald Fearing, a roboticist at the University of California at Berkeley. For one thing, the rules of aerodynamics change at very tiny scales and require wings that flap in precise ways - a huge engineering challenge.

Only recently have scientists come to understand how insects fly - a biomechanical feat that, despite the evidence before scientists' eyes, was for decades deemed "theoretically impossible." Just last month, researchers at Cornell University published a physics paper clarifying how dragonflies adjust the relative motions of their front and rear wings to save energy while hovering.

That kind of finding is important to roboticists because flapping fliers tend to be energy hogs, and batteries are heavy.

The CIA was among the earliest to tackle the problem. The "insectothopter," developed by the agency's Office of Research and Development 30 years ago, looked just like a dragonfly and contained a tiny gasoline engine to make the four wings flap. It flew but was ultimately declared a failure because it could not handle crosswinds.

Agency spokesman George Little said he could not talk about what the CIA may have done since then. The Office of the Director of National Intelligence, the Department of Homeland Security and the Secret Service also declined to discuss the topic.

Only the FBI offered a declarative denial. "We don't have anything like that," a spokesman said.

Researchers at the California Institute of Technology have made a "microbat ornithopter" that flies freely and fits in the palm of one's hand. A Vanderbilt University team has made a similar device.

With their sail-like wings, neither of those would be mistaken for insects. In July, however, a Harvard University team got a truly fly-like robot airborne, its synthetic wings buzzing at 120 beats per second.

"It showed that we can manufacture the articulated, high-speed structures that you need to re-create the complex wing motions that insects produce," said team leader Robert Wood.

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