Research on the radiation-resistant lightweight manipulator for fusion reactors

This paper proposes a design method for the Radiation-resistant Lightweight Manipulator (RLM) to address the needs of pipe cutting, welding, and grinding in vacuum vessels. By designing optimized and customized irradiation-resistant motors, resolver-based encoders, and external drive circuits, the irradiation resistance of the RLM joint module is enhanced. Based on the structural characteristics of RLM, the static stress-strain analyses are carried out to verify the effectiveness of the structural design. For the RLM force interaction operation task, a master-slave remote operation control mode based on the conductivity principle is proposed to achieve the force-flexibility control objective of the RLM operation process. Finally, to verify the reliability and radiation resistance of the RLM system in the strong radiation environment of the vacuum vessel, the radiation experiments are conducted on the joint motors and control system of the RLM. The experimental results show that the whole RLM motor and drive system can withstand a cumulative radiation dose of 5000 Gy with the addition of a special tungsten shielding structure, which proves the radiation resistance of the whole machine. • A radiation-resistant, lightweight manipulator design method is proposed. • RLM static analyses and strength validation are performed. • A master-slave remote handling model based on conductivity control is proposed. • Radiation experiments on RLM joint components are performed.