Document Type
Article
Publication Date
6-7-2019
Abstract
An objective understanding of human foot and ankle function can drive innovations of bio-inspired wearable devices. Specifically, knowledge regarding how mechanical force and work are produced within the human foot-ankle structures can help determine what type of materials or components are required to engineer devices. In this study, we characterized the combined functions of the foot and ankle structures during walking by synthesizing the total force, displacement, and work profiles from structures distal to the shank. Eleven healthy adults walked at four scaled speeds. We quantified the ground reaction force and center-of-pressure displacement in the shank’s coordinate system during stance phase and the total mechanical work done by these structures. This comprehensive analysis revealed emergent properties of foot-ankle structures that are analogous to passive springs: these structures compressed and recoiled along the longitudinal axis of the shank, and performed near zero or negative net mechanical work across a range of walking speeds. Moreover, the subject-to-subject variability in peak force, total displacement, and work were well explained by three simple factors: body height, mass, and walking speed. We created a regression-based model of stance phase mechanics that can inform the design and customization of wearable devices that may have biomimetic or non-biomimetic structures.
Journal Title
PLOS ONE
Volume
14
Issue
6
Recommended Citation
Hedrick EA, Stanhope SJ, Takahashi KZ (2019) The foot and ankle structures reveal emergent properties analogous to passive springs during human walking. PLoS ONE 14(6): e0218047. https://doi.org/10.1371/journal.pone.0218047
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Funded by the University of Nebraska at Omaha Open Access Fund
Comments
© 2019 Hedrick et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.