Biomimetic Finger Extension Mechanism for Soft Wearable Hand Rehabilitation Devices


For the rehabilitation and assistance of the hand functions, wearable devices have been developed, and the interest in tendon driven mechanisms have especially increased since it allows light weight and compact design. The tendon driven hand rehabilitation devices provides grasping force via exo-tendons routed on the dorsal and palmar sides of the hand pulled by remotely located actuators. However, most of the devices were not able to provide natural joint extension sequence of the finger and showed hyperextension of finger joints because the tendons for extension were fixed at the fingertip, concentrating the torque at the distal interphalangeal joint. In this study, a ring-type biomimetic finger extension mechanism was developed, which mimics the origin, structure, and orientation of the extensor tendon. The biomimetic mechanism was evaluated by comparing the motion with voluntary finger extension and the motion made by other conventional tendon driven finger extension mechanisms. The biomimetic extension mechanism provided the same joint extension sequence with voluntary finger extension, and the fully extended posture was most close to the voluntary finger extension among the tendon-driven mechanisms used in the experiments. The joint angle differences between the proposed tendon mechanism and the voluntary finger extension was -1.2° ± 3.4°, -2.9° ±2 .0°, and -3.1° ± 8.0° for distal phalangeal, proximal phalangeal, and metacarpo-phalangeal joint, respectively.

Meeting Name

2017 International Conference on Rehabilitation Robotics, ICORR 2017 (2017: Jul. 17-20, London, England)


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

Biomimetic design; Finger extension; Tendon driven mechanism; Wearable device

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)

1945-7898; 1945-7901

Document Type

Article - Conference proceedings

Document Version


File Type





© 2017 IEEE Computer Society, All rights reserved.

Publication Date

01 Jul 2017