As operators at the H.B. Robinson nuclear generating station in Hartsville, S.C., completed refueling last weekend, they had help from a few extra arms -- robotic arms, that is.

Progress Energy Inc., the plant's operator and owner, bought three robots from iRobot Corp., whose machines ventured into the Fukushima Daiichi reactor buildings in Japan last year to collect vital information about radiation, water levels and hazardous materials during the meltdowns.

The nuclear industry has been interested in robots for decades, but recent advances have made the technology far more attractive, according to Joseph Pollock, an executive director at the Nuclear Energy Institute.

The iRobot 710 is one of three robots Progress Energy used in a recent refueling at the H.B. Robinson nuclear generating station. The company hopes that its technology, designed originally for military use, will prove attractive to the energy industry, among others. Photo courtesy iRobot.

"What has opened the door is the development of robots' capabilities to move over and around obstacles that they could not do in the '80s and '90s," he said. "They could be used for routine inspections of plant areas or for investigations of abnormal indications."

The refueling that wrapped up this weekend was the first time Progress has used robots in a radiological area, said spokeswoman Jessica Lambert.

"It mitigates the risk by keeping personnel out of radioactive areas in our power plants," she said, noting that the robots are particularly valuable for their ability to do tasks with extreme precision.

iRobot, which also makes consumer products like the floor-cleaning Roomba, began with research conducted through the Defense Advanced Projects Research Agency (DARPA). The company's robots have been used to protect troops from improvised explosive devices in Iraq and Afghanistan and to investigate dangerous areas before sending in service members, said Tim Trainer, general manager for iRobot's military robot business.

"In Afghanistan they were used for some of the cave exploration missions," he said. "Soldiers certainly found that it was more desirable to have a robot go into a dark and unknown cave environment rather than them."

Progress' purchase is iRobot's first sale to the energy industry, but Trainer said he hopes it's just the beginning.

"It really is looking for early adopters and how they take this technology and make it useful in their operations," he said. "I think this is an emerging area for robotics and one that we're trying to get in on the ground floor."

Progress intends to use the robots -- two 510 PackBot models and a larger 710 Warrior -- for routine maintenance and inspections. Lambert said the robots would travel to service the company's entire nuclear fleet.