Speaker
Weijun Zhang
(Robotics Institute)
Description
The flexible in-vessel inspection system (FIVIS) for EAST is a unique 10-degree-of-freedom manipulator for its serial structure of arcuate deployed Big Arm and its planar Small Arm (end effector):the Big Arm takes the Small Arm to all positions of the toroidal vacuum vessel (VV) along its equatorial plane,achieving a full coverage of VV’s first wall. In the in-vessel inspection process, the Big Arm will stretch out as a hanging beam, the full extended configuration of which will reach a half of the toroidal VV. Significant offset from the center of D-shape section of VV is observed at the full extended posture of Big Arm due to its gravity and external payload during the prototype operation test, making it difficultto maintain the position accuracy of planned trajectory for inspection process. In this paper, By structural analysis and the finite element analysis methods, a simplified rigid-flexible model of FIVIS is adopted to calculate the deformations for fully extended and fullextracted configurations of Big Arm and effectors , The position accuracy tests have been performed by laser tracking system to validate the effectiveness of proposed stiffness model.A deflection compensation method has been presented to improve the stiffness ofBig Arm. Future work show that modal analysis methods is an effective tool to improve the dynamic performance of high precision position control of FIVIS
Co-author
Weijun Zhang
(Robotics Institute,Mechanical Engineering School, Shanghai Jiaotong University, Shanghai City, China)
