Robot 'insects' create a buzz

Insight on the News, April 7, 1997 by Kenneth Silber

In the next century, tiny robot aircraft will monitor war zones, disaster areas, other hot spots.

Imagine this: A large office building has collapsed, the result of an earthquake. Finding survivors would imperil the lives of rescue workers. What to do?

In the coming years, response teams to such disasters might turn to micro-air vehicles," or micro-AVs. Tiny robot aircraft the size of birds or even bees have become a hot topic for researchers developing new methods of surveillance, detecting hazardous chemicals and maintaining communications under difficult conditions.

At present, such devices exist only on drawing boards or as rudimentary prototypes. But the Defense Advanced Research Projects Agency a high-tech arm of the Pentagon, hopes to perform field tests of several versions of the aircraft within three years.

Engineers are studying a variety of design possibilities for micro-Ads, including fixed-wing rotary-blade crafts. Some contemplate flapping-wing vehicles that would emulate birds and insects. In any case, the aerodynamic principles of tiny aircraft are different from those employed by their larger counterparts. "At some point, the physics will definitely change, but we're not sure where," says Georgia Tech research scientist Sam Blankenship.

Researchers are trying to avoid the dangers posed by propellers or other sharp objects to passersby. And since many missions would require multiple micro-Ads operating in tandem, they will have to communicate with one another. Other engineers have begun to work on devices able to carry small payloads-soil samples from contaminated areas, for instance.

Researchers envision a variety of uses for micro aircraft:

* Combat support. Ground soldiers could launch airborne drones at critical moments to identify enemy troops or targets.

* Emergency services. Airborne chemical sensors could determine the presence of toxic materials at damaged industrial facilities or amid truck or train wrecks.

* Security patrols. Micro AVs might perform routine monitoring of the perimeters of prisons or military bases, conduct searches of border areas for drug traffickers and illegal immigrants and monitor remote highways to report auto accidents.

One long-term project is "an insect-sized vehicle that could fly into a room and plant itself in a corner unnoticed," says Stephen Morris, president of MLB Co., an aeronautical consulting firm in Palo Alto, Calif.

Scientists are focusing their efforts on prototypes 6 inches long or less that weigh several ounces and can stay aloft for more than half an hour. Some already have flown test missions. Morris, for example, has built several radio-controlled planes ranging from 6 to 9 inches long, as well as a 2-foot-long version that comes equipped with video cameras and is controlled via a television set.

He and his colleagues emphasize that micro aircraft must operate with a considerable degree of autonomy. While a new generation of microchips has made such a goal feasible, numerous technical hurdles remain before micro-Ads can maneuver tight spaces. "To be most useful, these things would have to go places where you can't see them," says Blankenship.

One final consideration: The miniature aircraft must be affordable, since such vehicles frequently will be lost or destroyed. Researchers aim to develop highly sophisticated micro-Ads that would cost as little as $1,000 each. "You can imagine how you might end up in a situation where every fire truck and every police car would have one of these things," says Blankenship.