Design and implementation of 3-DOF gripper for maintenances tasks in EAST vacuum vessel

EAST, a non-circular advanced steady-state plasma experimental device, will greatly rely on robotic technology to accomplish the in-vessel inspection and maintenance between experimental sessions without breaking the machine conditioning. In this prospect, a multi-link robot called EAST Articulated Maintenance Arm (EAMA), jointly undertaken by CEA-IRFM and ASIPP, has been developed to implement various maintenance tasks depend on different tools to be plugged at the front head of the arm. Due to high energetic plasma, the Plasma Facing Components (PFCs) could be damaged during EAST operation. The 3-DOF gripper consists of camera and claw offering accurate visual inspection and debris grasping inside EAST Tokamak. The dedicated gripper has some creative features with reference to other devices known in the industrial application, relating to particular the environment, the workspace, and the sensory equipment. In this paper, the main design specifications are described. The proposed choices made on the mechanics, the electronics, the control system and the joint motion control were discussed. Integration adaptation and experimental evaluation of the gripper has been provided to demonstrate the feasibilities of the gripper. Some optimizations that will be applied in the next version of the gripper are being considered.