In this disaster, officials have found that even dogs trained for search and rescue have not been able to climb across much of the debris, and the dust-laden air has diminished the dogs' keen sense of smell.
The experimental robots that did prove useful in New York look like mini-tanks with treads. Using a device similar to a joystick, Murphy can direct the small machines to wiggle, crawl, and travel into voids as deep as 30 feet (10 meters).
Murphy said the experimental robots have had "no real impact" on the rescue mission in part because there are so few of them. "It's like one guy showing up to a construction site with six nail guns. You need everybody to have a nail gun to make an impact," she said. "This is truly like finding needles in a haystack."
Instead, the simplest kind of technology"bucket brigades"has been one of the most effective search techniques at the World Trade Center site. Hundreds of rescue workers are removing rubble by passing buckets of it from hand to hand.
The experience in New York, however, gives Murphy and other engineers insights that can help them design search-and-rescue robots that are smarter, faster, and more independent, which is critical in most disasters.
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