Please wait a minute...
Submit  |   Chinese  | 
Advanced Search
   Home  |  Online Now  |  Current Issue  |  Focus  |  Archive  |  For Authors  |  Journal Information   Open Access  
Submit  |   Chinese  | 
Engineering    2018, Vol. 4 Issue (4) : 471 -478
Research |
Unpowered Knee Exoskeleton Reduces Quadriceps Activity during Cycling
Ronnapee Chaichaowarat(),Jun Kinugawa,Kazuhiro Kosuge
Department of Robotics, Tohoku University, Sendai 980-8579, Japan

Cycling is an eco-friendly method of transport and recreation. With the intent of reducing the energy cost of cycling without providing an additional energy source, we have proposed the use of a torsion spring for knee-extension support. We developed an exoskeleton prototype using a crossing four-bar mechanism as a knee joint with an embedded torsion spring. This study evaluates the passive knee exoskeleton using constant-power cycling tests performed by eight healthy male participants. We recorded the surface electromyography over the rectus femoris muscles of both legs, while the participants cycled at 200 and 225W on a trainer with the developed wheel-accelerating system. We then analyzed these data in time–frequency via a continuous wavelet transform. At the same cycling speed and leg cadence, the median power spectral frequency of the electromyography increases with cycling load. At the same cycling load, the median power spectral frequency decreases when cycling with the exoskeleton. Quadriceps activity can be relieved despite the exoskeleton consuming no electrical energy and not delivering net-positive mechanical work. This fundamental can be applied to the further development of wearable devices for cycling assistance.

Keywords Augmentation      Cycling      Energy cost      Electromyography      Exoskeleton      Knee      Orthosis      Muscle activity     
Corresponding Authors: Ronnapee Chaichaowarat   
Just Accepted Date: 24 July 2018   Issue Date: 11 September 2018
E-mail this article
E-mail Alert
Articles by authors
Ronnapee Chaichaowarat
Jun Kinugawa
Kazuhiro Kosuge
Cite this article:   
Ronnapee Chaichaowarat,Jun Kinugawa,Kazuhiro Kosuge. Unpowered Knee Exoskeleton Reduces Quadriceps Activity during Cycling[J]. Engineering, 2018, 4(4): 471 -478 .
URL:     OR
[1] Xiaohong Zheng, Zewen Zhu, Xiao Lin, Yi Zhang, Yi He, Hongbin Cao, Zhi Sun. A Mini-Review on Metal Recycling from Spent Lithium Ion Batteries[J]. Engineering, 2018, 4(3): 361 -370 .
[2] Andrea Di Maria, Karel Van Acker. Turning Industrial Residues into Resources: An Environmental Impact Assessment of Goethite Valorization[J]. Engineering, 2018, 4(3): 421 -429 .
[3] Jorge L. Escobar Ivirico, Maumita Bhattacharjee, Emmanuel Kuyinu, Lakshmi S. Nair, Cato T. Laurencin. Regenerative Engineering for Knee Osteoarthritis Treatment: Biomaterials and Cell-Based Technologies[J]. Engineering, 2017, 3(1): 16 -27 .
Copyright © 2015 Higher Education Press & Engineering Sciences Press, All Rights Reserved.