Work

Matching the Hip Variable Stiffness Feature by an Unpowered Hip Exoskeleton Reduces the Metabolic Cost of Human Walking

Year: 2025

Type: article

Abstract: Unpowered exoskeletons provide assistance for human walking by recycling negative mechanical energy from lower limb joints. However, current studies fail to further improve the effect of metabolic reduction due to a lack of an optimal match with the variable stiffness of lower limb joints during walking. We analyzed the feature of stiffness variation in the human hip joint and designed an unpowered hip exoskeleton to match that feature. The proposed exoskeleton utilized a mechanism composed of a cam and a linear spring to provide a moment variable in stiffness. This exoskeleton, manually adjustable to fit wearers, reduced the metabolic cost of human walking by $9.14~\pm ~0.85$ % (mean ± s.e.m.) compared to not wearing the exoskeleton. In addition, we found that heavier wearers achieved optimal assistive effects by using exoskeletons with higher stiffness. Our study further enhanced the effectiveness of exoskeletons by optimizing their stiffness feature, which has guiding significance for the subsequent development of exoskeletons.

Source: IEEE Transactions on Neural Systems and Rehabilitation Engineering

DOI: 10.1109/tnsre.2025.3578774

Authors: Hanwen Zhang, Zhuoran Li, Qinhao Zhang, Tiancheng Zhou, Wenbin Chen, Caihua Xiong

Institution: Huazhong University of Science and Technology

Language: English

Topic: Prosthetics and Rehabilitation Robotics

Subfield: Biomedical Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,075