New underwater robot to explore Fukushima containment vessel

Following the disaster that took place there in 2011, a survey on the primary containment vessel (PCV) of Unit 3 in 2015 found it had flooded with coolant to a depth of 6m. Fuel and debris inside the PCV must be mapped in order to move forward with the plant’s clean-up, but the vessel’s access point is just 14cm in diameter.

The underwater ROV (remotely operated vehicle) developed by Toshiba and IRID is 13cm in diameter and 30cm long. Once inside Unit 3’s PCV, front and rear camera and LED lights will deliver a live video feed to the operators. The radiation-hardened robot will be controlled via a wire, its four rear thrusters and single front thruster guiding it through the coolant, helping the team to assess the damage.

“We have already developed remotely operated robots for inspections at Fukushima,” said Goro Yanase, general manager of Toshiba’s Nuclear Energy Systems & Services Division.