A Transparent Lower Limb Perturbator to Investigate Joint Impedance During Gait

Ronald C. van ’t Veld*, S. S. Fricke, Ander Vallinas Prieto, Arvid Q.L. Keemink, Alfred C. Schouten, H. van der Kooij, E. H.F. van Asseldonk

*Corresponding author for this work

Research output: Chapter in Book/Conference proceedings/Edited volumeChapterScientificpeer-review

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Joint impedance plays an important role in postural control and movement. However, current experimental knowledge on lower limb impedance during gait is limited to the ankle joint. We designed the LOwer limb PERturbator (LOPER) aimed to assess knee and hip joint impedance during gait. The LOPER applies force perturbations with a 39 Hz bandwidth, tested on a free-hanging leg. In minimal impedance mode, peak interaction forces during walking are low (< 5 N). Also, this mode has a negligible effect on the gait pattern, as it is smaller than the within-subject variability during normal walking. In short, the LOPER is a transparent device able to elicit a clear response at both hip and knee joints to investigate lower limb dynamics. A second motor added to the LOPER could improve isolation of the perturbation contribution to knee and hip dynamics. People with neurological disorders can benefit from knowledge of joint impedance during gait through improved biomimetic devices and clinical decision making.

Original languageEnglish
Title of host publicationConverging Clinical and Engineering Research on Neurorehabilitation IV
Subtitle of host publicationProceedings of the 5th International Conference on Neurorehabilitation (ICNR2020), October 13–16, 2020
EditorsDiego Torricelli, Metin Akay, Jose L. Pons
ISBN (Electronic)978-3-030-70316-5
ISBN (Print)978-3-030-70315-8
Publication statusPublished - 2022
EventICNR 2020: International Conference on NeuroRehabilitation (Virtual) -
Duration: 13 Oct 202016 Oct 2020

Publication series

NameBiosystems and Biorobotics
ISSN (Print)2195-3562
ISSN (Electronic)2195-3570


ConferenceICNR 2020: International Conference on NeuroRehabilitation (Virtual)

Bibliographical note

Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care
Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.


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