DESIGN AND APPLICATION RESEARCH OF AN ADAPTIVE VARIABLE-DIAMETER PIPELINE ROBOT

This paper explores the innovative development and application of a continuously steerable, variable-diameter pipeline robot with active and passive drive capabilities, aimed at addressing the maintenance challenges of pipeline systems in long-term operation of hydroelectric generator units.To overcome the high cost and prolonged cycle time of traditional manual cleaning, a robot adaptable to complex pipeline environments-including straight pipes, curved pipes, T-shaped branches, and variable-diameter sections-has been designed.This robot features active diameter adjustment, active-passive drive integration, and continuous steering capabilities.It integrates both cleaning and grasping functions, employing a high-expansion-ratio scissor mechanism to accommodate pipelines of varying diameters.A three-screw parallel robotic arm ensures high-precision operation, while a tracked mobility mod-ule enhances stability in vertical pipelines.The motor drive and transmission systems have been meticulously de-signed, and the dynamics and inverse kinematics of both locomotion and the robotic arm have been systematically analyzed.To ensure the accuracy and reliability of the design and calculations, SolidWorks modeling, finite element simulations, and NX MCD dynamic validation were conducted.This study not only improves the efficiency of pipe-line maintenance but also provides valuable insights for the future design of small-scale pipeline robots capable of handling large-diameter variations.