Development and Design of Self-Adaptive Variable Diameter Robot for In-Pipe Inspection

Abstract

Pipeline defects such as aging, corrosion and cracks may result in the structural failure of industry pipelines, causing environmental pollution, energy waste and even catastrophic accidents of explosion. In-pipe inspection robots are regarded as an expected non-destructive testing tool of analyzing and evaluating in-pipe defects. This paper built a simple variable-diameter pipeline platform based on real pipeline environment. The movement of robots was analyzed to meet the functional requirements of variable diameter and obstacle-crossing. A design scheme of automated in-pipe robot with self-adaptive various diameter mechanism was developed, where a parallelogram connecting rod mechanism combining spring and feed screw nut pair was employed to adapt the diameter change of pipelines from 200mm to 250mm, actively and forcedly. Moreover, a digital camera device was equipped to perform on-line macro detections and in-pipe image acquirements. The results indicate that designed robot system has good various diameter properties. The work provides a reference for subsequent designs of in-pipe inspection robots.