Examining the mechanics of rope bending over a three-dimensional edge in ascending robots

This paper presents the analysis of ropes’ bending on three-dimension edges by ascending robots. A rope ascending robot (RAR) is a type of exterior wall-working robot that utilizes a synthetic rope to traverse the outer surface of a building. Rope-based façade cleaning robots demonstrate effective performance in well-structured buildings. However, in unstructured buildings, the rope used by these robots may become entangled or caught on various structures, presenting a significant challenge for their operation. If the rope becomes caught on a structure, the robot will be unable to move to its intended position. In more severe cases, the rope may become damaged, leading to potential failure or even a fall of the robot. Therefore, solving this problem is crucial for safe and efficient robot operation. Consequently, this study defines the issue of the rope becoming caught on a structure as a rope-locking problem and analyzes it by categorizing it based on the dimensions of contact between the rope and the edge. To address the varying tension experienced in different areas, the rope was divided into micro units and subjected to a three-dimensional analysis to resolve the rope-locking problem. Additionally, the analysis was verified by experiments.