Application of isomorphic remote manipulators with haptic feedback in the development of automatic analysis equipment for spent fuel reprocessing samples

Acid concentration and plutonium valence state in samples are crucial analytical parameters for process control during spent fuel reprocessing. Due to the high radioactivity and strong corrosiveness of reprocessing samples, remote operation is mandatory. A master-slave isomorphic teleoperation robot with haptic feedback function has been developed for the transfer of radioactivity sample in automated analysis devices through program control, which additionally provides manual operation capabilities in a master-slave mode. The isomorphic teleoperation robot was made up of a master arm and a slave arm, the master arm was equipped with an established Universal Robots (UR) system to ensure reliable operation.This study develops a radiation-hardened teleoperation system with a gear-coupled slave arm that centralizes electronics in a shielded base. We propose position-force coupling algorithms for precise joint control and a sensorless haptic rendering method enabling real-time force feedback. The design ensures operational fidelity while protecting components in high-radiation environments.Notably, compared to cable-driven systems, fully gear-driven manipulators provide superior structural stiffness through rigid meshing transmission, effectively minimizing elastic deformation and backlash. This mechanical advantage is complemented by advanced sensorless force feedback algorithms - notably, the system can translate effective payload on the slave arm into precise feedback force without physical force sensors, enabling real-time force display on the master arm.Therefore, the operator can perceive the operating conditions of the slave arm. The master-slave isomorphic remote manipulators had brought safety and efficiency for operations, and has been successfully applied in automatic analysis and equipment maintenance in highly radioactive environments.