PipeEye's robot managed to touch down on the mine's floor through the fourth borehole. Its cameras captured images of wire mesh that had been used to stabilize the mine's ceiling but were instead hanging down to the floor. "All we could see was piles of rocks and mud," says James Milward, PipeEye's senior technician. Conditions on the mine's floor "were worse than we expected," Murphy adds. With continued seismic activity blowing holes in the mine's walls, the floor was filled with water and debris.
Unable to provide the rescuers with much information, the robot was left down the borehole overnight. Unfortunately, when the crew returned to retrieve it the next morning they discovered that the hole had shifted and the robot could no longer make its way back to the surface. Despite several attempts to remove the robot, including using a 400-pound chisel to break up the ground blocking its escape, the $35,000 robot became permanently trapped 52 feet below the surface. "It's in the mountain forever," Milward says.
Given more time, Milward is convinced he and his team could have designed a robotic device better suited for the situation. The robot used was just barely small enough to fit through the borehole. "If we do anymore work in this industry,'' he says, "we would use a smaller version."
Murphy hopes that lessons learned at Crandall Canyon will be incorporated into any standards that the U.S. Commerce Department's National Institute of Standards and Technology, or NIST, develops for future rescue robotics. Since every disaster is different, the best robotics designs give rescuers the most flexibility, she says, adding, "You never get it all right, even if you think you know what's down there."
It is crucial that robotic rescue devices be well crafted before they are sent into harsh conditions such as those found at Crandall Canyon. This includes having a watertight body with sensors and camera equipment positioned higher up on the robot so that they are less likely to be blocked by debris. All of this needs to be done to help workers on the surface operating the robot. The long hours and harsh conditions at a rescue site make it "unreasonable to expect that people will be able to compensate for any of the technology's shortcomings on-site," Murphy says.