Research on automated methods for fastener disassembly and collection in railway maintenance and construction

The disassembly and collection of railway fasteners are critical components of track maintenance, directly influencing the efficiency, safety, and sustainability of railway operations. Currently, manual operations are hindered by high labour intensity and safety risks, while semi-automatic equipment remains limited by its reliance on manual positioning. Specialized machinery often suffers from low collection rates and poor compatibility across diverse fastener types. Although various robotic disassembly technologies have been proposed, existing solutions face significant challenges, including coaxiality deviations between the end-effector and the nut assembly, and insufficient compensation for angular and positional misalignments during high-speed execution. To address these issues, this paper proposes a novel fully automated railway fastener disassembly and collection system. The system integrates a specialized pneumatic end-effector with a universal joint limiting mechanism designed for angular deviation compensation and high-speed swing suppression. Furthermore, a modular mechanical architecture comprising six core functional modules is developed to realize a continuous material handling sequence from disassembly to centralized storage. A test platform simulating realistic railway operating conditions was constructed to conduct comparative experiments under varying lateral offsets. The results demonstrate that the proposed configuration achieves a 100% operational success rate under lateral deviations of 0–2.0 mm and maintains an 80% success rate at a maximum deviation of 3.0 mm, significantly outperforming conventional configurations. These findings provide a robust technical reference for the intelligent transformation of railway maintenance by enhancing operational reliability and reducing manual intervention.