Dimensional design method based on stability analysis to enhance traversability of heavy-duty hexapod robots over challenging terrains

Abstract

This paper presents a dimensional design methodology for heavy-duty hexapod robots, aiming to improve terrain traversability in field environments. Traditional robot design approaches often rely on iterative design loops or empirical adjustment, with stability validation typically performed at the final stages. In contrast, our proposed method integrates the Static Stability Margin directly into the early design process, enabling constrained the robot’s body dimensions, leg workspace, and center of mass. This allows systematic prediction of geometric configurations that satisfy diverse terrain mobility requirements while reducing the times of physical iterations. The proposed approach is founded on a static stability framework, which analytically establishes the relationship between robot geometric parameters and critical terrain parameters, including slope angle, lateral slope, ravine width, and obstacle height. This enables hexapod robots to achieve broader terrain adaptability through design. To validate the effectiveness of the proposed method, a hexapod simulation model is constructed according to the design results, and its performance is evaluated across various terrain scenarios. These results are then compared with physical experiments using the Elspider-IV prototype. The results show that the redesigned robot experiences reduced joint forces and achieves a more compact structure, aligning with the metrics of terrain-adaptive design. Overall, this method offers a generalizable and effective strategy for the dimensional design of heavy-duty legged robots.