Robotic control vehicle for measuring radiation in Fukushima Daiichi Nuclear Power Plant

The authors developed a robotic control vehicle for measuring the radiation in the Fukushima Daiichi Nuclear Power Plant. There are a lot of hotspots in the nuclear power plant (over several tens mSv/h). Heavy radiation prevents humans from searching and reconstructing it. It is essential to measure the radiation to ensure worker safety. The developed robotic control vehicle can measure radiation using a γ-cam and TALON with a radiation sensor. A heavily shielded operation box was built for reducing the exposure of radiation to 1/3. Two operators control the TALON and the γ-cam from the shielded operation box. Because of its pinhole mechanism, the γ-cam needs to know the distance to the targets. The 3-D light detection and ranging (LIDAR) was built for distance measurement. It has wide measurement range of up to 20m. Using the 3-D LIDAR and the shielded operation box can reduce the exposure during radiation measurement. The use of the developed robotic control vehicle can realize safe radiation measurement.