The New Mobile Infantry

Battle-ready robots are rolling out of the research lab and into harm's way.

Lieutenant Colonel John Blitch retired from the Army last fall, filling out the paperwork in an out-processing office of the Pentagon on the morning of September 10, 2001. In his three years at the helm of the Defense Department's Tactical Mobile Robots Program, Blitch had funded nearly a dozen academic and corporate research efforts. Their goal: building bots to replace human soldiers and rescue workers in dangerous situations. Barrel-chested and brawny, the 43-year-old Special Forces officer was leaving to direct the Center for Intelligent Robotics and Unmanned Systems at the Science Applications International Corporation, an engineering outfit and defense contractor in Littleton, Colorado. He planned to start the 1,500-mile drive the following day.

With news of the terrorist attacks, though, Blitch scrapped the trip. He removed his belongings from the flatbed trailer hitched to his pickup, loaded up a set of tactical mobile robots, or TMRs - most about the size of a football and fitted with rugged treads and an assortment of sensors - and headed for New York. On the road, Blitch donned his fatigues, dug out his military ID, and worked his cell phone, summoning colleagues from Florida to Boston to pack up their finest tactical robots and rendezvous at Ground Zero. "When I arrived, we passed through 32 checkpoints," he recalls. "People were asking, 'Who is this guy in camouflage running around with grad students and robots?'"

Over the next 11 days, the group's 17 robots squeezed into spaces too narrow for humans, dug through heaps of scalding rubble, and found seven bodies trapped beneath the mountains of twisted steel and shattered concrete. While that was only a tiny portion of the 252 victims recovered by rescue workers, the success triggered a deluge of fawning press ("AGILE IN A CRISIS, ROBOTS SHOW THEIR METTLE," announced The New York Times. "ROBOTS HELP WHERE HUMANS FEAR TO TREAD," echoed the Houston Chronicle). The publicity helped Blitch avoid a berating from his superiors for skirting regulations and passing off specious credentials (technically, he was retired).

More important, the mission proved the viability of Blitch's grand ambition: "to build robots that can do things human soldiers can't do, or don't want to do." Although the machines at Ground Zero were used for search-and-rescue, the real-world test reinvigorated researchers developing more versatile soldier robots to handle reconnaissance, live combat, and all-purpose warfare.

While robotic research has been trudging forward for nearly a half century, TMRs are a fairly recent innovation. Darpa launched its program in 1997 under the leadership of Eric Krotkov, a former Carnegie-Mellon roboticist and an expert in planetary rovers. Krotkov signed up the first 10 contractors for an initial five-year, $50 million initiative. Blitch took over one year later, funding 25 major projects and more than a dozen smaller ones - all told, they produced 43 prototypes and 18 unique robots.

Today, more than 40 Darpa-backed companies and academic labs are developing robots. There are recon machines that can be air-dropped into enemy territory and relay back intelligence data in real time. There are 3-pound surveillance bots that frontline soldiers could lob through a window or around a corner to get an audio and video preview of conditions. There are robots that can negotiate harsh terrain, scurry up stairs, or rush into battle to rescue injured soldiers pinned down by heavy shelling or gunfire. Other machines in development can carry weapons, deliver jolts of electricity, sniff for biogerms, and see through walls. There's even a walking robot, which could lead soldiers around blind corners, drawing fire from potential snipers. "We needed one of those in Somalia," says Blitch as he watches a demo video of the biped bot that's been spliced with gory scenes from Saving Private Ryan.

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