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
The effort to develop search and rescue robots was launched in earnest following the Oklahoma City bombing in 1995. Blitch helped out in that rescue effort, and that convinced him that research sponsored by the Department of Defense could help in the development of new tools to help future rescues.
He was in a position to know. As a program manager at the Defense Advanced Research Projects Agency, the Pentagon's funding arm for far-out projects, he had funded research on miniature robotics for military reconnaissance.
He began funding civilian research projects, including Murphy's, and that has led to some pretty innovative thinking in the field of robotics.
Howie Choset, associate professor of mechanical engineering in the Robotics Institute of Carnegie Mellon University, has been working for some time now on an articulated snake that could worm its way into the debris left by a natural or human-caused disaster.
He's made some progress, but much more will be needed if his strange-looking beast is ever to be useful. It looks like a metallic snake, with joints that allow it to work its way into very tight spaces.
The prototype built in his lab, however, can't move like a real snake, partly because it is tethered to a mobile platform.
"It's sort of like an elephant," he says.
Like an elephant's trunk, the snake dangles off the face of the platform, so its reach is not very long. He is working now on rescue snakes that would be completely autonomous, thus allowing them to penetrate deep within a disaster area. Enormous technological challenges lie ahead, however, in the development of devices that will be mobile and robust enough to work in such a difficult environment.
It's worth a try, he says, because it could mean the difference between life and death.
"Just locating a victim and saying 'hey, help is on the way,' could save lives right there," he says. "And if you can get him food, water and oxygen, that's icing on the cake."
Meanwhile, mechanical engineering professors Michael Goldfarb and Ephrahim Garcia of Vanderbilt University have developed tiny, insect-like robots about a third the size of a credit card.
These ingenious devices can climb through rubble, like real insects, carrying sensors to detect such things as explosives, and infrared sensors that could reveal the presence of life, or tiny cameras to send back images of a disaster scene. They are being developed for the military, but could have an application in search and rescue as well.
The goal of all these research programs is the same — to send in mechanical devices where it might be too hazardous, or too inaccessible, for human rescuers. They will, however, never be anything more than tools.
"No matter how good these things are at getting into confined spaces, they aren't going to pick somebody up and pull them out of there," Blitch says. "That's too complex a task for a machine. It requires a lot of adaptive, intuitive types of behavior that are just beyond the machine world."
But maybe, just maybe, they might lift some of the burden from those very tired shoulders we've all seen working in the dust and the rubble where twin towers once stood.
Lee Dye’s column appears weekly on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.