The design and implementation of distributed architecture in the CMOR motion control system

Abstract

The CMOR Motion Control System is a multi-degree-of-freedom, long-beam, heavy-duty robot system with end effectors used to maintain the blanket and divertor of the China Fusion Engineering Test Reactor (CFETR) with irregular structural geometry. Since the multi-degree of freedom, large size, and flexible structure of the fusion robot will increase the complexity of the algorithm, it is necessary to design the corresponding control system and auxiliary algorithm to realize the motion control of the robot. In this paper, a feasible CMOR (CFETR Multipurpose Overload Robot) motion control system architecture is proposed, which adopts the distributed control structure of the upper and lower machine. Firstly, the game theory algorithm decouples the macro arm with 9-degree-freedom and the micro arm with 14 degree-of-freedom (dual 7-DOFs robots) and separates the pose and accuracy targets after planning the motion of the target task with the Markov chain. Secondly, to improve the accuracy, the kinematics controller based on macro arm motion planning strategy for initial positioning and the force-position hybrid controller based on micro arm motion planning strategy for compensation for precise positioning are designed separately. Finally, a robot distributed architecture is designed to realize offline and online simulation and control in which the offline mode simulates a collision-free trajectory based on the game theory and the online mode synchronously displays fusion robot motion by digital twin technology. The feasible CMOR motion control system architecture is proposed in this paper which can assist complex algorithms to achieve intelligent control in the fusion application.