Comparison of the human-exosuit interaction using ankle moment and ankle positive power inspired walking assistance

Martin Grimmer, Brendan T. Quinlivan, Sangjun Lee, Philippe Malcolm, Denise Martineli Rossi, Christopher Siviy, Conor J. Walsh

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Previous ankle exoskeleton assistance techniques that were able to demonstrate metabolic reductions can be categorized into those that delivered moment profiles similar to the biological ankle moment throughout the stance phase, and others that delivered positive power only during push off. Both assistance techniques and a powered-off condition were compared in treadmill walking (1.5 m s −1 ) with a soft exosuit. We hypothesized that both techniques can result in a similar metabolic reduction when providing a similar level of average positive exosuit power at each ankle (0.12 W kg −1 ) and hip (0.02 W kg −1 ) while the underlying global center-of-mass and local joint biomechanics would be different. We found a similar net metabolic rate reduction of 15% relative to walking with the suit powered-off for both techniques. The ankle moment inspired technique showed larger magnitudes of reductions for biological moment and power at the hip and the ankle. The ankle power inspired technique might benefit from higher biological efficiency, when reducing positive instead of negative power at the knee and when almost keeping the isometric function of the plantarflexors before push-off. Changes at the ankle caused energetic reductions at the knee, hip and the center-of-mass. A major contribution to metabolic reduction might be based on them. As the lower limb biomechanics that led to these reductions were different, we believe that humans alter their gait to maximize their energetic benefit based on the exosuit assistance. For further insights on mechanisms that lead to metabolic reduction, joint mechanics and muscle-tendon dynamics must be analyzed in combination.

Original languageEnglish (US)
Pages (from-to)76-84
Number of pages9
JournalJournal of Biomechanics
Volume83
DOIs
StatePublished - Jan 23 2019

Fingerprint

Ankle
Walking
Hip
Biomechanical Phenomena
Knee
Joints
Joints (anatomy)
Exercise equipment
Biomechanics
Mechanics
Gait
Tendons
Lower Extremity
Muscle
Muscles

Keywords

  • Assistance
  • Control
  • Exosuit
  • Moment
  • Power

ASJC Scopus subject areas

  • Biophysics
  • Orthopedics and Sports Medicine
  • Biomedical Engineering
  • Rehabilitation

Cite this

Comparison of the human-exosuit interaction using ankle moment and ankle positive power inspired walking assistance. / Grimmer, Martin; Quinlivan, Brendan T.; Lee, Sangjun; Malcolm, Philippe; Rossi, Denise Martineli; Siviy, Christopher; Walsh, Conor J.

In: Journal of Biomechanics, Vol. 83, 23.01.2019, p. 76-84.

Research output: Contribution to journalArticle

Grimmer, Martin ; Quinlivan, Brendan T. ; Lee, Sangjun ; Malcolm, Philippe ; Rossi, Denise Martineli ; Siviy, Christopher ; Walsh, Conor J. / Comparison of the human-exosuit interaction using ankle moment and ankle positive power inspired walking assistance. In: Journal of Biomechanics. 2019 ; Vol. 83. pp. 76-84.
@article{ef715ec2bf834e439c98ef0d036b3d2f,
title = "Comparison of the human-exosuit interaction using ankle moment and ankle positive power inspired walking assistance",
abstract = "Previous ankle exoskeleton assistance techniques that were able to demonstrate metabolic reductions can be categorized into those that delivered moment profiles similar to the biological ankle moment throughout the stance phase, and others that delivered positive power only during push off. Both assistance techniques and a powered-off condition were compared in treadmill walking (1.5 m s −1 ) with a soft exosuit. We hypothesized that both techniques can result in a similar metabolic reduction when providing a similar level of average positive exosuit power at each ankle (0.12 W kg −1 ) and hip (0.02 W kg −1 ) while the underlying global center-of-mass and local joint biomechanics would be different. We found a similar net metabolic rate reduction of 15{\%} relative to walking with the suit powered-off for both techniques. The ankle moment inspired technique showed larger magnitudes of reductions for biological moment and power at the hip and the ankle. The ankle power inspired technique might benefit from higher biological efficiency, when reducing positive instead of negative power at the knee and when almost keeping the isometric function of the plantarflexors before push-off. Changes at the ankle caused energetic reductions at the knee, hip and the center-of-mass. A major contribution to metabolic reduction might be based on them. As the lower limb biomechanics that led to these reductions were different, we believe that humans alter their gait to maximize their energetic benefit based on the exosuit assistance. For further insights on mechanisms that lead to metabolic reduction, joint mechanics and muscle-tendon dynamics must be analyzed in combination.",
keywords = "Assistance, Control, Exosuit, Moment, Power",
author = "Martin Grimmer and Quinlivan, {Brendan T.} and Sangjun Lee and Philippe Malcolm and Rossi, {Denise Martineli} and Christopher Siviy and Walsh, {Conor J.}",
year = "2019",
month = "1",
day = "23",
doi = "10.1016/j.jbiomech.2018.11.023",
language = "English (US)",
volume = "83",
pages = "76--84",
journal = "Journal of Biomechanics",
issn = "0021-9290",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Comparison of the human-exosuit interaction using ankle moment and ankle positive power inspired walking assistance

AU - Grimmer, Martin

AU - Quinlivan, Brendan T.

AU - Lee, Sangjun

AU - Malcolm, Philippe

AU - Rossi, Denise Martineli

AU - Siviy, Christopher

AU - Walsh, Conor J.

PY - 2019/1/23

Y1 - 2019/1/23

N2 - Previous ankle exoskeleton assistance techniques that were able to demonstrate metabolic reductions can be categorized into those that delivered moment profiles similar to the biological ankle moment throughout the stance phase, and others that delivered positive power only during push off. Both assistance techniques and a powered-off condition were compared in treadmill walking (1.5 m s −1 ) with a soft exosuit. We hypothesized that both techniques can result in a similar metabolic reduction when providing a similar level of average positive exosuit power at each ankle (0.12 W kg −1 ) and hip (0.02 W kg −1 ) while the underlying global center-of-mass and local joint biomechanics would be different. We found a similar net metabolic rate reduction of 15% relative to walking with the suit powered-off for both techniques. The ankle moment inspired technique showed larger magnitudes of reductions for biological moment and power at the hip and the ankle. The ankle power inspired technique might benefit from higher biological efficiency, when reducing positive instead of negative power at the knee and when almost keeping the isometric function of the plantarflexors before push-off. Changes at the ankle caused energetic reductions at the knee, hip and the center-of-mass. A major contribution to metabolic reduction might be based on them. As the lower limb biomechanics that led to these reductions were different, we believe that humans alter their gait to maximize their energetic benefit based on the exosuit assistance. For further insights on mechanisms that lead to metabolic reduction, joint mechanics and muscle-tendon dynamics must be analyzed in combination.

AB - Previous ankle exoskeleton assistance techniques that were able to demonstrate metabolic reductions can be categorized into those that delivered moment profiles similar to the biological ankle moment throughout the stance phase, and others that delivered positive power only during push off. Both assistance techniques and a powered-off condition were compared in treadmill walking (1.5 m s −1 ) with a soft exosuit. We hypothesized that both techniques can result in a similar metabolic reduction when providing a similar level of average positive exosuit power at each ankle (0.12 W kg −1 ) and hip (0.02 W kg −1 ) while the underlying global center-of-mass and local joint biomechanics would be different. We found a similar net metabolic rate reduction of 15% relative to walking with the suit powered-off for both techniques. The ankle moment inspired technique showed larger magnitudes of reductions for biological moment and power at the hip and the ankle. The ankle power inspired technique might benefit from higher biological efficiency, when reducing positive instead of negative power at the knee and when almost keeping the isometric function of the plantarflexors before push-off. Changes at the ankle caused energetic reductions at the knee, hip and the center-of-mass. A major contribution to metabolic reduction might be based on them. As the lower limb biomechanics that led to these reductions were different, we believe that humans alter their gait to maximize their energetic benefit based on the exosuit assistance. For further insights on mechanisms that lead to metabolic reduction, joint mechanics and muscle-tendon dynamics must be analyzed in combination.

KW - Assistance

KW - Control

KW - Exosuit

KW - Moment

KW - Power

UR - http://www.scopus.com/inward/record.url?scp=85057480863&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85057480863&partnerID=8YFLogxK

U2 - 10.1016/j.jbiomech.2018.11.023

DO - 10.1016/j.jbiomech.2018.11.023

M3 - Article

C2 - 30514626

AN - SCOPUS:85057480863

VL - 83

SP - 76

EP - 84

JO - Journal of Biomechanics

JF - Journal of Biomechanics

SN - 0021-9290

ER -