Configurable, wearable sensing and vibrotactile feedback system for real-time postural balance and gait training: proof-of-concept

Junkai Xu; Tian Bao; Ung Hee Lee; Catherine Kinnaird; Wendy Carender; Yangjian Huang; Kathleen H Sienko; Peter B Shull

doi:10.1186/s12984-017-0313-3

Configurable, wearable sensing and vibrotactile feedback system for real-time postural balance and gait training: proof-of-concept

J Neuroeng Rehabil. 2017 Oct 11;14(1):102. doi: 10.1186/s12984-017-0313-3.

Authors

Junkai Xu¹, Tian Bao², Ung Hee Lee², Catherine Kinnaird², Wendy Carender³, Yangjian Huang¹, Kathleen H Sienko^{2

4}, Peter B Shull⁵

Affiliations

¹ State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China.
² Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA.
³ Vestibular Testing Center, Department of Otolaryngology, University of Michigan, Ann Arbor, MI, USA.
⁴ Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
⁵ State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China. pshull@sjtu.edu.cn.

Abstract

Background: Postural balance and gait training is important for treating persons with functional impairments, however current systems are generally not portable and are unable to train different types of movements.

Methods: This paper describes a proof-of-concept design of a configurable, wearable sensing and feedback system for real-time postural balance and gait training targeted for home-based treatments and other portable usage. Sensing and vibrotactile feedback are performed via eight distributed, wireless nodes or "Dots" (size: 22.5 × 20.5 × 15.0 mm, weight: 12.0 g) that can each be configured for sensing and/or feedback according to movement training requirements. In the first experiment, four healthy older adults were trained to reduce medial-lateral (M/L) trunk tilt while performing balance exercises. When trunk tilt deviated too far from vertical (estimated via a sensing Dot on the lower spine), vibrotactile feedback (via feedback Dots placed on the left and right sides of the lower torso) cued participants to move away from the vibration and back toward the vertical no feedback zone to correct their posture. A second experiment was conducted with the same wearable system to train six healthy older adults to alter their foot progression angle in real-time by internally or externally rotating their feet while walking. Foot progression angle was estimated via a sensing Dot adhered to the dorsal side of the foot, and vibrotactile feedback was provided via feedback Dots placed on the medial and lateral sides of the mid-shank cued participants to internally or externally rotate their foot away from vibration.

Results: In the first experiment, the wearable system enabled participants to significantly reduce trunk tilt and increase the amount of time inside the no feedback zone. In the second experiment, all participants were able to adopt new gait patterns of internal and external foot rotation within two minutes of real-time training with the wearable system.

Conclusion: These results suggest that the configurable, wearable sensing and feedback system is portable and effective for different types of real-time human movement training and thus may be suitable for home-based or clinic-based rehabilitation applications.

Keywords: Balance training; Gait retraining; Wearable systems.

MeSH terms

Aged
Biofeedback, Psychology*
Equipment Design
Exoskeleton Device*
Female
Gait / physiology*
Gait Disorders, Neurologic / rehabilitation
Healthy Volunteers
Humans
Male
Postural Balance / physiology*
Psychomotor Performance
Software
Touch
Vibration