Updated Feb. 9, 2015, The Japan Times: ” HITACHI, IBARAKI PREF. – A snakelike robot designed to examine the interior of one of the three meltdown-hit reactors at the Fukushima No. 1 nuclear power plant is ready to begin its expedition.
Assessing the damage in the reactors is a crucial step in decommissioning the poorly protected plant, which was crippled by core meltdowns triggered by the Great East Japan Earthquake and tsunami in March 2011.
Remote-controlled robots are essential for the job because the radiation in the reactors chambers is so high it would kill any person who got close.
Using information gathered by the robot, Tokyo Electric Power Co., the plant operator, plans to repair the damaged chambers enough so they can be filled with water in preparation to remove the melted radioactive debris, an operation planned to begin in about a decade.
The 60-cm-long robot, developed by electronics giant Hitachi and its nuclear affiliate Hitachi-GE Nuclear Energy, was demonstrated this week at a Hitachi-GE facility northeast of Tokyo. It is expected to enter the No. 1 reactor as early as April, officials said.
It has a lamp at the front and is designed to crawl like a snake through a 10-cm-wide pipe into the containment vessel. From there it must dangle and descend onto a platform just below the reactor core’s bottom, an area known as the pedestal.
There, the robot is to transform into a U-shaped crawler and capture live images and temperature and radiation levels and transmit them to a control station outside the building.
Expectations for the robot probe are high after earlier efforts at assessment met with limited success.
“Depending on how much data we can collect from this area, I believe (the probe) will give us a clearer vision for future decommissioning,” Hitachi-GE engineer Yoshitomo Takahashi said.
After its exploratory trip, which will make the robot extremely radioactive, technicians plan to store it in a shielded box. They have no plans to reuse it.
Different robots must be designed for each reactor, since each is slightly different.
According to computer simulations, all of the fuel rods in unit 1 probably melted and pooled at the bottom of the containment chamber, but there had been no way of confirming that until now.
A brief fiberscope observation conducted in 2012 produced images that were scratchy and of limited use.
To assess the debris at the bottom of the damaged reactor chambers, which are usually filled with water, an amphibious robot is being developed for deployment next year.
The damage from the melted fuel burned holes in the reactors, thwarting efforts to fill them with cooling water. As a result, water must be pumped into them continuously, producing an endless stream of radiation-contaminated water that is hampering the plant’s cleanup process. ”
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Posted Feb. 6, 2015, The Asahi Shimbun: ” HITACHI, Ibaraki Prefecture–A new shape-changing robot has been rolled out that can chart previously inaccessible areas of the damaged containment vessels at the crippled Fukushima No. 1 nuclear power plant.
The new device was demonstrated Feb. 5 at a plant owned by Hitachi-GE Nuclear Energy Ltd., one of the firms involved in its development. The International Research Institute for Nuclear Decommissioning, an organization made up of electric power companies and nuclear power plant manufacturers, developed it with a government subsidy.
The probe was conceived as a way to examine the containment vessels, which are too radioactive for humans to enter. It is scheduled for deployment at the No. 1 reactor building, which contains melted fuel, this spring.
The tubular-shaped robot, measuring 60 centimeters long in its normal state, can transform itself depending on the space it is trying to enter and the task to perform.
In the demonstration at the factory, the robot, in its tubular form, made its way through a pipe with a diameter of 10 cm. On the other side of the pipe, it changed shape to crawl around and capture images of the area.
The plan is to have the probe access the containment vessels through the holes in the wall through which electrical power lines pass.
Because strong radiation is harmful to electronic machines as well, the robot’s camera is only guaranteed to function for 10 hours. The device can also take radiation and temperature readings. ”
source with short clip of the new robot