Multi‐Wheel Cooperative Simultaneous Climbing Control for Bridge Pier Defects DetectionCircular Frame Robot System

To address the limitations of traditional unmanned aerial vehicles (UAVs) and wall‐climbing robots in bridge‐pier defect detection, this research proposes a circular‐climbing robot specifically designed for bridge piers. First, based on the geometric characteristics of bridge piers and their construction environment, a circular robot frame is designed, and its mechanical behavior is analyzed to determine the conditions for stable climbing. Second, based on attitude information collected by multiple gyroscopes, an attitude estimation method for the circular robot and a multi‐wheel cooperative motion control algorithm are developed. On this basis, a multi‐motor master–slave fuzzy proportional integral derivative (PID) controller is implemented on a field programmable gate array (FPGA) platform to perform fuzzy inference on the attitude information, generate real‐time control parameters, and adaptively adjust the speeds of the crawling mechanisms, thereby achieving coordinated motion control of the multi‐wheel system. Finally, experiments are conducted to verify the system's reliability in terms of climbing stability and motion control accuracy. A comparative analysis further shows that the proposed robot exhibits a more stable mechanical structure and greater adaptability than existing wall‐climbing robots, and offers advantages in contact pressure adjustment, load capacity, and scalability, enabling it to carry various bridge pier inspection devices for different application needs. This work provides a practical platform for the automated health monitoring of bridge piers.