Design and Accuracy of an Instrumented Insole Using Pressure Sensors for Step Count.

TitleDesign and Accuracy of an Instrumented Insole Using Pressure Sensors for Step Count.
Publication TypeJournal Article
Year of Publication2019
AuteursNgueleu, AM, Blanchette, AK, Bouyer, LJ, Maltais, D, McFadyen, BJ, Moffet, H, Batcho, CS
JournalSensors (Basel)
Volume19
Issue5
Date Published2019 Feb 26
ISSN1424-8220
Abstract

Despite the accessibility of several step count measurement systems, count accuracy in real environments remains a major challenge. Microelectromechanical systems and pressure sensors seem to present a potential solution for step count accuracy. The purpose of this study was to equip an insole with pressure sensors and to test a novel and potentially more accurate method of detecting steps. : Five force-sensitive resistors (FSR) were integrated under the heel, the first, third, and fifth metatarsal heads and the great toe. This system was tested with twelve healthy participants at self-selected and maximal walking speeds in indoor and outdoor settings. Step counts were computed based on previously reported calculation methods, individual and averaged FSR-signals, and a new method: cumulative sum of all FSR-signals. These data were compared to a direct visual step count for accuracy analysis. : This system accurately detected steps with success rates ranging from 95.5 ± 3.5% to 98.5 ± 2.1% (indoor) and from 96.5 ± 3.9% to 98.0 ± 2.3% (outdoor) for self-selected walking speeds and from 98.1 ± 2.7% to 99.0 ± 0.7% (indoor) and 97.0 ± 6.2% to 99.4 ± 0.7% (outdoor) for maximal walking speeds. Cumulative sum of pressure signals during the stance phase showed high step detection accuracy (99.5 ± 0.7%⁻99.6 ± 0.4%) and appeared to be a valid method of step counting. : The accuracy of step counts varied according to the calculation methods, with cumulative sum-based method being highly accurate.

DOI10.3390/s19050984
Alternate JournalSensors (Basel)
PubMed ID30813515
PubMed Central IDPMC6427154
Grant ListIT07003 / / MEDTEQ-MITACS /