UPDATE: The Associated Press reports that the robots have detected peak radiation levels of around 50 millisieverts per hour inside units 1 and 3 (World Nuclear News also has a nice summary of the range of numbers seen, and what they mean). The bottom line is that rates in some places at least are far too high for human workers to enter the plant. The readings point to a long and difficult clean up process. You can read more about what the numbers mean here.
Over the weekend, remote-controlled robots entered the Fukushima Daiichi nuclear power plant. The robots took the first photos inside the units 1 and 3 reactors (right) and assessed radiation levels. The Tokyo Electric Power Company (TEPCO), which runs the plant, sent Packbots, from the American company iRobot.
Packbots are used for explosive ordinance disposal in Iraq and Afghanistan, but in the wake of the nuclear accident iRobot sent two to Fukushima, along with two larger Warrior bots. The robots are equipped with cameras and radiation detector equipment, and are even capable of opening doors (presuming they’re not locked). Normally the robots are radio-controlled, but iRobot installed a fiber-optic link on the models at Fukushima, to make it easier to operate them in the harsh radiation environment that is believed to exist inside the plant.
Click here for more on the role of robots at Fukushima.