Configuration Design of an Adaptive Knee Exoskeleton with Axial Support

doi:10.3901/JME.260722

Abstract

Abstract: Focusing on the mechanical etiology of knee osteoarthritis, a knee joint axial support method based on a wearable exoskeleton is proposed to alleviate cartilage wear caused by excessive loading, thereby achieving conservative treatment goals. Addressing the requirement for knee joint offloading, the design concept of an axial-supporting knee joint offloading exoskeleton is first introduced. Based on the kinematic characteristics of the knee joint, an equivalent mechanism model and its kinematic model are established. To resolve the issue of human-exoskeleton kinematic mismatches, a method for exoskeleton configuration synthesis based on the linear correlation of kinematic screws is proposed, resulting in a series of exoskeleton configurations capable of adapting to knee joint motion while providing axial support. Taking two typical mechanisms, RRR and RPR, as examples, the kinematics, Jacobian matrix, and statics model of the closed-loop mechanism formed by the human and exoskeleton are derived and validated through simulation. The mechanisms of kinematic adaptability and mechanical assistance of the afore mentioned mechanisms are further analyzed. Equivalent substitution methods and examples are proposed for the corresponding mechanisms to extend their applicability across different scenarios. Finally, the effectiveness of the proposed exoskeleton configuration in actual wearability is further validated through prototype experiments involving both passive and active exoskeletons.

Key words: adaptive, axial support, knee exoskeleton, configuration design

CLC Number:

TH112

GUO Yu, ZHANG Qingdong, DONG Jinan, LIU Jianxin, CHEN Ziming. Configuration Design of an Adaptive Knee Exoskeleton with Axial Support[J]. Journal of Mechanical Engineering, 2026, 62(15): 350-365.

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URL: http://www.cjmenet.com.cn/EN/10.3901/JME.260722

http://www.cjmenet.com.cn/EN/Y2026/V62/I15/350

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