The United States is sending specialised robots to Japan to help officials get control of the Fukushima Daiichi nuclear power plants damaged in this month's devastating earthquake and tsunami.

Dr Peter Lyons, an acting assistant secretary for nuclear energy with the Department of Energy, told a Senate panel on Tuesday that the government is shipping radiation-hardened robots to assist the Japanese. He said the robots could begin to give Japanese and US officials readings on the environment inside the nuclear power plants that were badly damaged during the 9.0 magnitude earthquake and the subsequent tsunami that rocked the nation on 11 March.

The robots could be sent into areas that would be dangerous for humans to enter because of high radiation levels.

Lyons, speaking in front of the Senate Energy and Natural Resources Committee, did not specify how many robots are going, but did say they would arrive soon and are being sent at the request of the Japanese government.

"The government of Japan has been very, very interested in understanding the capabilities that could be brought to bear from this country," said Lyons. "We have provided that information. They have identified needs. We are moving expeditiously to ship not only the robots but also operators who perhaps will be used to train Japanese operators. We don't know yet how close the operators will need to be to the site."

When asked about getting information about the state of the damaged reactors, Lyons said the robots could provide some information. "Certainly not all we need, but some," he added.

The robots aren't the only aid the US is sending. Lyons said the Department of Energy has also sent 40 people to Japan, along with 17,000 pounds of equipment.

A little more than a week ago, Massachusetts-based iRobot shipped four remote-controlled robots to help the Japanese military with its daunting relief efforts. The company, which in the past has sent robots to aid rescue and cleanup efforts in the area affected by the Gulf of Mexico oil spill and at Ground Zero after the 11 September 2001, terrorist attacks, also has six employees in Japan helping to train others to use the machines.

Tim Trainer, vice-president at iRobot, told Computerworld that the robots could be used for search-and-rescue missions, and there's a strong possibility that they will be sent into the damaged nuclear facilities.

All four of iRobot's machines that have been sent to Japan are equipped with multiple cameras and can be operated from up to half a mile away. "People can stay at a safe distance and evaluate obstructions and the security and safety of a building," Trainer said.