THE PROJECT
A UK and Japan collaboration on long-reach robotics.
LongOps was a research and development collaboration between Britain and Japan, born from the 2019 UK Japan robotics agreement, to work out how advances in robotics could make fission and fusion decommissioning faster and safer. It was led by RACE, the UKAEA centre for Remote Applications in Challenging Environments, and focused on two long-term use cases: the Fukushima Daiichi reactors owned by TEPCO, and the JET fusion machine at Culham. Funding was shared equally between UK Research and Innovation, the Nuclear Decommissioning Authority and TEPCO.
THE CHALLENGE
A multi-metre arm cannot behave as rigid.
An arm that has to reach several metres inside a reactor bends under its own weight, and every movement leaves the tip oscillating for seconds after the joints have stopped. The operator either waits it out or works with a model that says the tip is somewhere it is not. The usual fix is to put sensors on the arm and measure what it is really doing. Inside a reactor that option does not exist: sensors do not survive, and there is no way to go in and service them.
HEROBOTS IN THE PROJECT
Modelling, digital twin and vibration control.
We developed the modelling algorithms, the digital twin and the vibration control for long-reach flexible manipulators, and delivered them to the programme. They were tested first on our own flexible-link testbed, a rig with revolute and prismatic joints and elastic links, built to behave like the manipulators used in nuclear remote operations. They were then applied to the robots the programme targeted: TARM, the multi-tonne articulated manipulator housed at RACE, and the Fukushima Daiichi system. Results were demonstrated at Herobots to the UKAEA and TEPCO teams. Vibration was reduced by up to 97%, with no additional sensors on the robot.
Vibration control
Control algorithms that suppress oscillation in long, flexible links.
Real-time simulation
Models that run at the speed of the operation.
VR teleoperation
Virtual reality teleoperation of the manipulator.
Digital twin
A realistic twin of long-reach flexible manipulators.
PROJECT IN NUMBERS
PARTNERS / FUNDING
Partners
UKAEA, RACE (lead) · TEPCO.
Sites
Fukushima Daiichi, Japan · JET, Culham, UK.
Funding
UK Research and Innovation · Nuclear Decommissioning Authority · TEPCO.