Design of a standalone joint module toward real EAST in-vessel operation use

Abstract

The remote handling in-vessel inspection manipulator for China’s Experimental Advanced Superconducting Tokamak (EAST) has proven its survivability in 120°C high temperature environment and its kinematics feasibility in full-scale tokamak mock-up. To adapt this manipulator for real in-vessel operation use, most of its joint components, such as motors, reducers, and transmission structures must be considered for possible contamination to the tokamak in-vessel ambient. In order to verify the feasibility of combining vacuum sealing techniques with the previous in-vessel inspection manipulator solution, we have designed a standalone rotary joint module as prototype for relevant experimental tests. The joint module has a standard stainless steel metallic bellow to seal all its ordinary commercial joint components from tokamak environment, while the servo control wires, sensor wires and active cooling tubes inside the sealed chamber are led out by special vacuum feedthroughs. Basic mobility tests have been carried out under equivalent vacuum environment. This paper mainly presents the joint module design and related vacuum environment tests result of this prototype joint module. Further work will concentrate on adapting the whole in-vessel manipulator for vacuum environment operation based on this joint module design and tokamak environment tests result.