Examination of the performance characteristics of velostat as an in-socket pressure sensor
Author(s)
Hopkins, Matthew
Vaidyanathan, Ravi
McGregor, Alison H
Type
Journal Article
Abstract
Velostat is a low-cost, low-profile electrical bagging material with piezoresistive properties, making it an attractive option for in-socket pressure sensing. The focus of this research was to explore the suitability of a Velostat-based system for providing real-time socket pressure profiles. The prototype system performance was explored through a series of bench tests to determine properties including accuracy, repeatability and hysteresis responses, and through participant testing with a single subject. The fabricated sensors demonstrated mean accuracy errors of 110 kPa and significant cyclical and thermal drift effects of up to 0.00715 V/cycle and leading to up to a 67% difference in voltage range respectively. Despite these errors the system was able to capture data within a prosthetic socket, aligning to expected contact and loading patterns for the socket and amputation type. Distinct pressure maps were obtained for standing and walking tasks displaying loading patterns indicative of posture and gait phase. The system demonstrated utility for assessing contact and movement patterns within a prosthetic socket, potentially useful for improvement of socket fit, in a low cost, low profile and adaptable format. However, Velostat requires significant improvement in its electrical properties before proving suitable for accurate pressure measurement tools in lower limb prosthetics.
Date Issued
2020-03-04
Date Acceptance
2020-02-22
Citation
IEEE Sensors Journal, 2020, 20 (13), pp.6992-7000
ISSN
1530-437X
Publisher
Institute of Electrical and Electronics Engineers (IEEE)
Start Page
6992
End Page
7000
Journal / Book Title
IEEE Sensors Journal
Volume
20
Issue
13
Copyright Statement
© 2020 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
The Royal British Legion
Identifier
https://ieeexplore.ieee.org/document/9024130
Grant Number
BMPF_P60304
Subjects
Analytical Chemistry
0205 Optical Physics
0906 Electrical and Electronic Engineering
0913 Mechanical Engineering
Publication Status
Published
Date Publish Online
2020-03-04