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CLC number: TP242.6

On-line Access: 2020-05-18

Received: 2019-08-30

Revision Accepted: 2020-04-21

Crosschecked: 2020-04-30

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Citations:  Bibtex RefMan EndNote GB/T7714


Hugh M. Herr


Xing-bang Yang


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Frontiers of Information Technology & Electronic Engineering  2020 Vol.21 No.5 P.723-739


An untethered cable-driven ankle exoskeleton with plantarflexion-dorsiflexion bidirectional movement assistance

Author(s):  Tian-miao Wang, Xuan Pei, Tao-gang Hou, Yu-bo Fan, Xuan Yang, Hugh M. Herr, Xing-bang Yang

Affiliation(s):  School of Mechanical Engineering and Automation, Beihang University, Beijing 100083, China; more

Corresponding email(s):   hherr@media.mit.edu, xingbang@mit.edu

Key Words:  Ankle exoskeleton, Plantarflexion-dorsiflexion bidirectional assistance, Biological gait torque, Cable-driven, Gait detection

Tian-miao Wang, Xuan Pei, Tao-gang Hou, Yu-bo Fan, Xuan Yang, Hugh M. Herr, Xing-bang Yang. An untethered cable-driven ankle exoskeleton with plantarflexion-dorsiflexion bidirectional movement assistance[J]. Frontiers of Information Technology & Electronic Engineering, 2020, 21(5): 723-739.

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author="Tian-miao Wang, Xuan Pei, Tao-gang Hou, Yu-bo Fan, Xuan Yang, Hugh M. Herr, Xing-bang Yang",
journal="Frontiers of Information Technology & Electronic Engineering",
publisher="Zhejiang University Press & Springer",

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%T An untethered cable-driven ankle exoskeleton with plantarflexion-dorsiflexion bidirectional movement assistance
%A Tian-miao Wang
%A Xuan Pei
%A Tao-gang Hou
%A Yu-bo Fan
%A Xuan Yang
%A Hugh M. Herr
%A Xing-bang Yang
%J Frontiers of Information Technology & Electronic Engineering
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%@ 2095-9184
%D 2020
%I Zhejiang University Press & Springer
%DOI 10.1631/FITEE.1900455

T1 - An untethered cable-driven ankle exoskeleton with plantarflexion-dorsiflexion bidirectional movement assistance
A1 - Tian-miao Wang
A1 - Xuan Pei
A1 - Tao-gang Hou
A1 - Yu-bo Fan
A1 - Xuan Yang
A1 - Hugh M. Herr
A1 - Xing-bang Yang
J0 - Frontiers of Information Technology & Electronic Engineering
VL - 21
IS - 5
SP - 723
EP - 739
%@ 2095-9184
Y1 - 2020
PB - Zhejiang University Press & Springer
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DOI - 10.1631/FITEE.1900455

Lower-limb assisted exoskeletons are widely researched for movement assistance or rehabilitation training. Due to advantages of compliance with human body and lightweight, some cable-driven prototypes have been developed, but most of these can assist only unidirectional movement. In this paper we present an untethered cable-driven ankle exoskeleton that can achieve plantarflexion-dorsiflexion bidirectional motion bilaterally using a pair of single motors. The main weights of the exoskeleton, i.e., the motors, power supplement units, and control units, were placed close to the proximity of the human body, i.e., the waist, to reduce the redundant rotation inertia which would apply on the wearer’s leg. A cable force transmission system based on gear-pulley assemblies was designed to transfer the power from the motor to the end-effector effectively. A cable self-tension device on the power output unit was designed to tension the cable during walking. The gait detection system based on a foot pressure sensor and an inertial measurement unit (IMU) could identify the gait cycle and gait states efficiently. To validate the power output performance of the exoskeleton, a torque tracking experiment was conducted. When the subject was wearing the exoskeleton with power on, the muscle activity of the soleus was reduced by 5.2% compared to the state without wearing the exoskeleton. This preliminarily verifies the positive assistance effect of our exoskeleton. The study in this paper demonstrates the promising application of a lightweight cable-driven exoskeleton on human motion augmentation or rehabilitation.


王田苗1,裴轩1,侯涛刚1,2,樊瑜波3,5,杨轩1,Hugh M. HERR4,杨兴帮4



Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article


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