Abstract: Up to now, more than 30 kinds of robots were used in Unit 1/2/3 of Fukushima Daiichi NPP for aerial survey of the reactor building exterior, decontamination of work area and walkway, investigation of water leakage from primary containment vessel, the reactor building interior and the primary containment vessel interior. Eight of these robots broke down during operation mainly because of radiation damage and blocking of obstacles. The good practice and lessons learned from the deployment of robots in Fukushima NPP are worth for reference in the R&D and practical application of nuclear robot. Nuclear robot should be paid more attention and be developed in serialarity. Except for the high radiation field above dozens of Gy/h, the space accessibility and control performance,not the radiation tolerance,are usually the decisive factors to the practical application of nuclear robot. When used in the radiation field below 10 Gy/h, cumulative dose management and exchange of core components are effective countermeasures to make up for the shortage of radiation tolerance design for general robots.

Key words: Fukushima accident, nuclear robot, radiation tolerance