A competition held at the annual conference of the American Association for Artificial Intelligence in Austin, Texas, was a big mess - deliberately. Researchers from the National Institute of Standards and Technology in Gaithersburg, Md., unveiled their take on urban decay with a three-stage obstacle course that they designed to quantify the search-and-rescue capabilities of robots. The course re-created three rooms from a collapsed building, showing progressively worse damage. The robots had to navigate debris, exposed rebar, gas leaks and unstable or missing floors to locate the infrared signatures of human victims, which were simulated by heating pads. The researchers hope that the establishment of a performance metric will enable designers and buyers to objectively evaluate robots for a particular application.