Radiation and corrosive seawater may deter Robots from saving the day at Fukushima. The Japanese are after Robots that can operate under the severe conditions found at the Daiichi nuclear reactor sites damaged by the tsunami and subsequent attempts to avert a meltdown.
While apologizing, Tokyo Electric Power Company?s (TEPCo) president says they are doing all they can to rectify the crisis situation. The company asked iRobot Corp in Bedford, Massachusetts, maker of the popular Roomba vacuum cleaner, to send over some of their military grade robots. Apparently, they don?t think the little vacuum robot is sufficient to soak up all the water and radiation.
A Canadian robotic company, Inuktun Services, has received inquiries as to how they might help. Japan itself is responding with their own Moni-Robo, the Disaster Monitoring Robot from Mitsui Engineering and Shipbuilding. Moni-Robo, can be likened to the so called "one-armed bandit" slot machines in Reno, Nevada. The device has only one arm, as well as a video camera for taking 3D thermographic images, sensors for measuring radioactivity and detecting combustible gases, elements dangerous to two armed humans. Let?s hope the bot hits the jackpot and finds ways to help.
Robots have been used successfully in the past for similar nuclear transgressions. A robotics professor from Carnegie Mellon University, William Whittaker, led a team over 30 years ago fixing Three Mile Island?s nuclear generating station in the US after a near meltdown occurred.
A demo ROV (remote operated vehicle), Versatrax, may have already been deployed from Inuktun?s Tokyo representative. The crawler bot with remote-controlled video camera was designed for inspecting pipes and sewers and other confined spaces. The Versatrax 100 can work in small 4 inch (10 centimeter) pipes. It can investigate up to 600ft (180m) of pipe and overcome obstacles and offset joints along the way.
Two Packbots and two Warriors, from iRobot landed with six engineers. They aren?t sure what, if any, assignments TEPCo will give them, considering their original purpose. Packbot comes equipped to do explosive ordinance disposal.
A radioactivity sensor has been added to Packbot, pretty important considering his assignment location. It is hoped he can relocate hazardous materials with his three-link arm capable of lifting 13.6 kilograms. The bot climbs 60 degree grades, goes up stairs and can travel at 9.3 kilometers per hour.
While still an unreleased prototype, the Warrior sent to Japan was modified to transport 6.4 centimeter fire hose, since water for cooling has been a major concern. The bot?s arm can lift up to about 150 pounds (100 kilograms), climb stairs on an adjustable track system, and moves out sharply at 12.9 kilometers per hour.
iRobot Warrior comes from iRobot’s military line of products
Tim Trainer, iRobot’s vice president of operations, says: "We sent the robots without a defined mission in place but to assist where appropriate, whether this means delivering water to the fuel rods, moving equipment within the facility or cleaning up the facility once fuel has become stable,"
Every company offering robots for the Fukushima Daiichi recovery needs to address the severe environment. The military grade iRobot units have integrated electromagnetic interference (EMI) shielding to cover the wiring, circuit boards and other vulnerable areas. They were modified with fiber-optic tethered spoolers in case radiation interferes with radio signals. Both the Packbot and Warriors can be tele-operated from 220 and 500 meters respectively according to Trainer.
Versatrax can handle medium level radiation and dosage. The bots are made of stainless steel so decontamination is made easier. Whitaker said, "In order to interface with humans [again] these robots also have to able to tolerate a high-pressure wash down." His bots at Three Mile Island sloshed through contaminated cooling water. iRobot models can manage about a meter of water, but unlike Inuktun bots, they weren?t designed to be submersible. However, they can sustain exposure to 170 to 180 millisieverts of radiation much better than the TEPCo workers who were hospitalized after stepping into contaminated water at Unit #3 at Fukushima.
TEPCo, established in 1951 as an electric power supplier to the metropolitan Tokyo area, has historically taken a big hit in customer satisfaction. TEPCo ordered closure of all its reactors after admitting to falsifying data in about 30 safety logs and up to 200 incidents. This included Fukushima Daiichi Unit-1 and seven reactors at the Kashiwazaki-Kariwa plant in Japan’s west coast which was built over a known earthquake fault line. Kashiwazaki-Kariwa was involved in the Niigataken Chuetsu-oki Earthquake of July 2007.
TEPCo apologizes on their website, and in typical Japanese fashion states: "We sincerely regret causing anxiety and inconvenience to our customers and the society."
They continue to explain: "Due to the serious damages caused to our nuclear power stations, thermal power stations and transmission systems, despite our efforts, to maintain stable supply of electricity has become impossible. We are very sorry but have decided to implement rolling blackouts."
The electric power company provided a link with scheduled blackout dates and times as of March 25. Blackouts, however, will be the least of their problems after the radioactive dust settles.
Fukushima Governor Sato is quoted as saying: "Considering the anxiety, anger and exasperation being felt by people in Fukushima, there is just no way for me to accept their apology."