Developing a Climbing Robot for Stay Cable Maintenance With Security and Rescue Mechanisms

The significance of climbing robotic systems for cable maintenance is escalating in both academic research and real-world applications. As these systems are poised for real-world deployment, it is imperative to develop security and rescue mechanisms that ensure robots' intrinsic safety and robustness in dealing with uncertainty factors. This study presents a novel cable climbing robot designed with a climbing platform, a robotic manipulator integrated with specialized maintenance tools, and a gripper to withstand dynamic loads and impacts from maintenance operations. In addition, we propose the variable-damping safe-landing mechanism, the rescue mechanism, and the fusible gripper mechanism to counteract substantial disturbances in worst-case scenarios. Extensive experiments have been conducted to evaluate the proposed robot and its security and rescue mechanisms. The cable climbing robot has a heavy-duty capacity of 45 kg and an obstacle-negotiation ability of 10 mm. It also demonstrated its capabilities in various maintenance tasks, such as cable inspection, grinding, or repair. The variable-damping safe-landing mechanism was tested, showing the maximum falling speed can decrease from 1 to 0.1 m/s to promise safety, and the falling time can increase from about 5 to 45 s. Meanwhile, the rescue mechanism successfully retrieved the trapped robot. The results demonstrate the capabilities of the cable climbing robot and the feasibility of using the security and rescue mechanisms for the climbing robotic system, which have implications that the cable climbing robot with security and rescue mechanisms is more reliable and can be deployed in the real world with greater confidence.