In the ongoing battle to clean up Japan’s crippled Fukushima Dai-ichi nuclear power plant, Toshiba is deploying a novel robot that’s a bit like a scorpion.
Developed with the International Research Institute for Nuclear Decommissioning (IRID), the cylindrical machine is designed to enter the primary containment vessel (PCV) of the Unit 2 reactor at the plant, which was heavily damaged by the 2011 earthquake and tsunami in northern Japan. The catastrophe sparked a nuclear emergency and long-term evacuations.
Toshiba wants to deploy the device to help determine the condition and location of melted-down fuel in the reactor, which is too dangerous for workers to enter. The effort is part of decommissioning work at the plant that’s expected to take decades.
The robot is 54 centimeters long, and can put itself right-side up if it topples over. It has a joint near its middle that allows it to raise its tail like a scorpion, bringing a camera and LED lights to bear on its environment, complementing another camera and LEDs in its nose section.
The video feed will be used by operators using devices resembling PlayStation game controllers. Control signals are sent to the robot through a wire. The 5 kilogram machine also has a thermometer and a dosimeter. It can withstand about 100 Sieverts per hour of radiation for 10 hours.
The robot could get hit by as much as 70 Sieverts per hour of radiation in the No. 2 reactor, which would be about seven times that encountered by robots that ventured into the No. 1 reactor, a Toshiba spokeswoman said.
In April, plant operator Tokyo Electric Power sent shape-shifting, snake-like robots developed by IRID and Hitachi-GE Nuclear Energy into the No. 1 reactor. One machine got stuck, but another helped provide a detailed look at the inside of the PCV.
Toshiba, which has produced a lifelike android robot and a line of robot vacuum cleaners, began development of the nuclear probe in 2013. It’s slated to be deployed in the next two months, but the electronics maker doesn’t have a backup unit in case it gets stuck.
Japan put all of its nuclear power plants offline following the 2011 disaster. Safety concerns, public opposition and legal disputes have kept the current tally of 43 plants out of service, but Kyushu Electric Power is scheduled to bring one of its plants back online in August.