Design and implementation of wormlike creeping robot system working at the bottom of the nuclear fusion vessel

Abstract

Maintenance for nuclear fusion vessel is crucial, yet it faces great difficulty due to the complex internal physical and geometric conditions. For this reason, such remote control mobile robot system is required to do the inboard detection and maintenance work instead of human beings. Under the above background, this paper presents a wormlike creeping robot system working on the V-shaped circular slot at the bottom of the EAST nuclear fusion vessel, and constructs the engineering prototype. The wormlike creeping robot adopts three-part structure, which consists of fore segment, mid segment and back segment connected by bidirectional universal joint. The fore and back segments stretch the paws to contact the surface of V-shaped slot, while the mid segment realizes the movement of robot by axial expansion. Functional analysis is devoted to modules of robot system. For the requirements of walking stability on the V-shaped slot, creeping gait planning is analyzed. Finally, the engineering prototype is running in the simulated vessel to test the synthesis movement properties and evaluate the mechanical properties. The test shows that the wormlike creeping robot system has good feasibility and effectiveness.