Design, development, and clinical validation of a two degrees of freedom compliant ankle-foot prosthesis based on a 4-4r parallel mechanism

Xiu, H; Han, Y; Wang, X; Zhang, Y; Liang, W; Wei, G; Ren, L; Ren, L

Abstract

Compared with active prostheses, passive compliant ankle prostheses offer the advantages of reduced energy consumption, a lighter weight, a simple structure, and lower costs. However, although various commercial products are available, these designs do not provide adequate degrees of freedom (DOFs) for movement. This paper presents a compliant passive ankle–foot prosthesis (CPAF) capable of 2-DOF rotation during locomotion. The CPAF uses a 2-DOF parallel mechanism to support the bodyweight and offer limited rotation during movement, and it incorporates a compliant component to facilitate and generate torque to conform to uneven terrains. The kinematics of the parallel mechanism, including the workspace and singularities, were investigated. Then, a prototype was developed, and the performance evaluations showed that sufficient torque could be generated with an appropriate range of motion for the ankle. Concequently, clinical validations were conducted: the dynamic analysis indicated that the CPAF provided good gait movement and generated sufficient ankle torque during level-ground walking, and the metabolic tests demonstrated that the configuration-4 of the compliant component could achieve the best efficiency during walking.

Citation

Xiu, H., Han, Y., Wang, X., Zhang, Y., Liang, W., Wei, G., …Ren, L. (2022). Design, development, and clinical validation of a two degrees of freedom compliant ankle-foot prosthesis based on a 4-4r parallel mechanism. Mechanism and Machine Theory, 172, 104818. https://doi.org/10.1016/j.mechmachtheory.2022.104818

• Journal Article Type: Article
• Acceptance Date: Feb 28, 2022
• Online Publication Date: Mar 6, 2022
• Publication Date: Jun 1, 2022
• Deposit Date: Mar 29, 2022
• Publicly Available Date: May 6, 2022
• Journal: Mechanism and Machine Theory
• Print ISSN: 0094-114X
• Publisher: Elsevier
• Volume: 172
• Pages: 104818
• DOI: https://doi.org/10.1016/j.mechmachtheory.2022.104818
• Publisher URL: https://doi.org/10.1016/j.mechmachtheory.2022.104818
• Related Public URLs: http://www.journals.elsevier.com/mechanism-and-machine-theory/
• Additional Information: Funders : National Key R&D Program of China; Grant Number: 2018YFC2001301