Abstract

Spinal cord injury can leave the affected individual severely disabled with a low level of independence and quality of life. Assistive upper-limb exoskeletons are one of the solutions that can enable an individual with tetraplegia (paralysis in both arms and legs) to perform simple activities of daily living by mobilizing the arm. Providing an efficient user interface that can provide full continuous control of such a device - safely and intuitively - with multiple degrees of freedom (DOFs) still remains a challenge. In this study, a control interface for an assistive upper-limb exoskeleton with five DOFs based on an intraoral tongue-computer interface (ITCI) for individuals with tetraplegia was proposed. Furthermore, we evaluated eyes-free use of the ITCI for the first time and compared two tongue-operated control methods, one based on tongue gestures and the other based on dynamic virtual buttons and a joystick-like control. Ten able-bodied participants tongue controlled the exoskeleton for a drinking task with and without visual feedback on a screen in three experimental sessions. As a baseline, the participants performed the drinking task with a standard gamepad. The results showed that it was possible to control the exoskeleton with the tongue even without visual feedback and to perform the drinking task at 65.1% of the speed of the gamepad. In a clinical case study, an individual with tetraplegia further succeeded to fully control the exoskeleton and perform the drinking task only 5.6% slower than the able-bodied group. This study demonstrated the first single-modal control interface that can enable individuals with complete tetraplegia to fully and continuously control a five-DOF upper limb exoskeleton and perform a drinking task after only two hours of training. The interface was used both with and without visual feedback.
Original languageEnglish
Article number739279
JournalFrontiers in Neuroscience
Volume15
Number of pages14
ISSN1662-4548
DOIs
Publication statusPublished - 17 Dec 2021

Bibliographical note

Copyright © 2021 Mohammadi, Knoche, Thøgersen, Bengtson, Gull, Bentsen, Gaihede, Severinsen and Andreasen Struijk.

Keywords

  • tongue computer interface
  • upper-limb exoskeleton
  • rehabilitation robotics
  • human-robot interaction
  • disabled individuals
  • assistive devices
  • tetraplegia

Fingerprint

Dive into the research topics of 'Eyes-free tongue gesture and tongue joystick control of a five DOF upper-limb exoskeleton for severely disabled individuals'. Together they form a unique fingerprint.

Cite this