Wrench-Based Stability Analysis for a Rope-Driven Wheel-Legged Robot

In our previous study, we introduced a rope-driven wheel-legged robot (RDWR) designed for climbing 3D facades. The RDWR utilizes a two-rope ascender and a wheel-legged mechanism to navigate complex surface geometries. Similar to other legged robots, stability analysis is crucial for the RDWR to prevent tipping over and ensure safe operation. In this paper, we propose a wrench-based stability analysis for the RDWR, integrating concepts from both legged robots and cable-driven parallel robots (CDPR). We define a stable region, which ensures static stability by preventing tip-overs, and present a new maneuvering strategy that synchronizes rope ascending/descending with legged movement to enhance stability during 3D facade traversal. We compute the stable region using the linear programming (LP) algorithm and validate its effectiveness, along with the proposed maneuvering strategy, through simulations.