Rescue workers faced with the heartbreaking task of combing through the rubble where the World Trade Center once stood have been getting a little help from some strange-looking mechanical contraptions.
Within hours after the terrorist attack on New York City and the Pentagon, scientists had moved robotic devices carrying cameras and heat-seeking sensors into the area to help search for survivors.
These are pretty crude devices, in some ways, because the field is still in its infancy. But they seem to have helped a little in the tragic aftermath of Sept. 11 by finding some remains and providing evidence that one void was too close to collapsing for search crews to enter.
Generally, these are camera and sensor platforms, mostly tracked vehicles, that crawl into tight or hazardous areas and send information back to the operators.
Longer term, scientists are developing more autonomous robots that can move into areas that are too small, or too dangerous, for humans.
The idea is to put the necessary tools — such as a night-vision camera or a heat sensor that could detect someone alive — aboard an expendable vehicle that could be sent into the rubble to see what's there before rescuers rush in and place themselves at peril.
Much progress has been made in recent years in developing fairly autonomous robots, like the Mars Pathfinder, but devices at disaster sites will have to work under extremely difficult circumstances ranging from intense heat to dust that can clog almost any mechanical device.
It's a tough challenge. And they will always be limited in what they can do.
Humans Are Key
Robots will never replace humans in the desperate effort to save others, says retired Army Lt. Col. John Blitch, director of the newly formed Center for Robot Assisted Search and Rescue, who rushed to New York from Washington with several robots to see if they could be of any help. They were, he says, but they were not nearly as valuable as "the real heroes in all this: the rescue guys and the firemen."
The robots were particularly helpful in sending back infrared images from heat emitted by objects in their field of view. That aided in the discovery of some body parts, and also alerted searchers to extremely hot areas where fire could be expected. But they didn't rescue anyone.
"Robots don't rescue anything," he adds. "People rescue people. What robots can do is provide assistance."
Robin R. Murphy, a computer scientist at the University of South Florida in Tampa, also rushed to New York following the disaster and headed up one of four teams working with Blitch. Murphy is a leader in the development of "marsupial robots," two machines that work together like the mothers and daughters of the marsupial world. One works as a supply van, the other as a reconnaissance vehicle.
She says her team had the most success with a "tethered robot," consisting of a shoebox-sized mobile platform connected to a larger machine that supplies such things as electrical power. The smaller device was able to work its way into some very tight areas, Murphy says, and it located some body parts and the remains of two victims, but no survivors.
The mobile platform was equipped with a camera that transmitted video images back to the "mother ship" which helped engineers determine that at least one area was too unsafe to enter.
"Having a video tape of this is just great," Murphy says. "They think of it as a camera on wheels."
Efforts Ramped Up