Design of a Passive Gravity Compensation Mechanism for Wearable Bilateral Lower Limb Exoskeletons
Tongshu Chen, Ke Shi, Maozeng Zhang, Aiguo Song
Abstract
Gravity compensation has been widely employed in lower limb exoskeletons to reduce leg load and alleviate muscle fatigue. Passive compensation approaches offer inherent safety and lightweight advantages; however, existing designs are often constrained by the bulk and complexity of spring-based mechanisms, which compromises the compactness and reliability of the exoskeleton. To address these limitations, a gravity compensation mechanism is developed for a wearable passive bilateral lower limb exoskeleton, featuring a compact, simple, and robust design. A unilateral compensation concept based on a synthetic centroid mapping method is first introduced and then extended to a bilateral configuration through a differential structure. Combined with an adaptive constant-force mechanism, the resulting system maintains structural simplicity and spatial efficiency, making it suitable for wearable applications with limited integration space. An exoskeleton prototype is constructed based on the proposed mechanism, and its performance is evaluated through experiments. The results demonstrate that the proposed system effectively compensates for leg weight during walking while maintaining a lightweight, low-complexity, and structurally robust design.
BibTeX
@inproceedings{ral2026_designofapassive,
title = {Design of a Passive Gravity Compensation Mechanism for Wearable Bilateral Lower Limb Exoskeletons},
author = {Tongshu Chen and Ke Shi and Maozeng Zhang and Aiguo Song},
booktitle = {RA-L 2026},
year = {2026}
}