It's not safe for humans to spend much time at the Fukushima-Daiichi power plant anymore. Four years ago, a massive tsunami hit the facility, triggering a core meltdown that earned the most severe ranking on the International Nuclear Scale—on par with the Chernobyl disaster in 1986. (It's worth noting, though, that far more radiation was released at Chernobyl than at Fukushima.)
And though the evacuation order for tens of thousands of people who once lived near the plant is expected to be lifted in the next year, the inside of the old power plant is still a mess: melted fuel rods, toxic water, and other debris that must be contained before a more comprehensive clean-up can begin.
And so, in one area of the plant—a spot where a person would risk too much radiation exposure after just 10 minutes—engineers placed a wheeled box the size of a refrigerator, one of the many robots that is cleaning up Fukushima.
It's called a manipulator, and it consists of a robotic arm that emerges from the box and can snake through the power plant to plug leaks. (An earlier manipulator robot that was deployed to find the leaks in the first place has already completed its mission.) Operators can attach various tools to the carbon fiber arm—a cutting tool that uses water jets, and a vent tube filled with grout to patch holes, for instance. Think of it like the Inspector Gadget of robots—one machine with a very long arm that can do all kinds of things.
"The arm itself when it's deployed is essentially a vertical mast, a telescoping tube that's five cylinders nested together just like a pirate's telescope," said Matt Cole, the director for robotics systems and services at Kurion, one of the companies that's contracted to help with the clean-up. "On the bottom of that, two hydraulically-powered pivots—we call it elbows—the elbows are what pivot it. On the end of that pivot is another three sets of telescoping tubes... At the end of that is a plate that allows us to connect any number of different tools."