By the time the sun rose on Friday, December 19th, the Homestead Miami race track had been taken over by robots. Some hung from racks, their humanoid feet dangling above the ground as roboticists wheeled them out of garages. One robot resembled a gorilla, while another looked like a spider; yet another could have been mistaken for a designer coffee table. Teams of engineers from MIT, Google, Lockheed Martin, and other institutions and companies replaced parts, ran last-minute tests, and ate junk food. Spare heads and arms were everywhere.

It was the start of the Robotics Challenge Trials, a competition put on by the Defense Advanced Research Projects Agency (DARPA), the branch of the US Department of Defense dedicated to high risk, high reward technology projects. Over a period of two days, the machines would attempt a series of eight tasks including opening doors, clearing a pile of rubble, and driving a car.

The eight robots that scored highest in the trials would go on to the finals next year, where they will compete for a $2 million grand prize. And one day, DARPA says, these robots will be defusing roadside bombs, surveilling dangerous areas, and assisting after disasters like the Fukushima nuclear meltdown.

Mark Gubrud, a former nanophysicist and frumpy professor sort, fit right in with the geeky crowd. But unlike other spectators, Gubrud wasn’t there to cheer the robots on. He was there to warn people.

“DARPA’s trying to put a face on it, saying ‘this isn’t about killer robots or killer soldiers, this is about disaster response,’ but everybody knows what the real interest is,” he says. “If you could have robots go into urban combat situations instead of humans, then your soldiers wouldn’t get killed. That’s the dream. That’s ultimately why DARPA is funding this stuff.”