Next Article in Journal
A Spaceborne Synthetic Aperture Radar Partial Fixed-Point Imaging System Using a Field- Programmable Gate Array−Application-Specific Integrated Circuit Hybrid Heterogeneous Parallel Acceleration Technique
Next Article in Special Issue
A Damping Grid Strapdown Inertial Navigation System Based on a Kalman Filter for Ships in Polar Regions
Previous Article in Journal
A Real-Time Contactless Pulse Rate and Motion Status Monitoring System Based on Complexion Tracking
Previous Article in Special Issue
A Cost-Effective Vehicle Localization Solution Using an Interacting Multiple Model−Unscented Kalman Filters (IMM-UKF) Algorithm and Grey Neural Network
Article Menu
Issue 7 (July) cover image

Export Article

Open AccessArticle
Sensors 2017, 17(7), 1492; doi:10.3390/s17071492

Static and Dynamic Accuracy of an Innovative Miniaturized Wearable Platform for Short Range Distance Measurements for Human Movement Applications

1
Information Engineering Unit, Department of Information Engineering, Political Sciences and Communication Sciences, University of Sassari, Sassari 07100 (SS), Italy
2
Department of Electronics and Telecommunications, Politecnico di Torino, Torino 10129 (TO), Italy
3
Department of Engineering and Applied Sciences, University of Bergamo, Dalmine 24044 (BG), Italy
*
Author to whom correspondence should be addressed.
Received: 8 May 2017 / Revised: 14 June 2017 / Accepted: 21 June 2017 / Published: 24 June 2017
(This article belongs to the Special Issue Inertial Sensors for Positioning and Navigation)
View Full-Text   |   Download PDF [20213 KB, uploaded 24 June 2017]   |  

Abstract

Magneto-inertial measurement units (MIMU) are a suitable solution to assess human motor performance both indoors and outdoors. However, relevant quantities such as step width and base of support, which play an important role in gait stability, cannot be directly measured using MIMU alone. To overcome this limitation, we developed a wearable platform specifically designed for human movement analysis applications, which integrates a MIMU and an Infrared Time-of-Flight proximity sensor (IR-ToF), allowing for the estimate of inter-object distance. We proposed a thorough testing protocol for evaluating the IR-ToF sensor performances under experimental conditions resembling those encountered during gait. In particular, we tested the sensor performance for different (i) target colors; (ii) sensor-target distances (up to 200 mm) and (iii) sensor-target angles of incidence (AoI) (up to 60 ). Both static and dynamic conditions were analyzed. A pendulum, simulating the oscillation of a human leg, was used to generate highly repeatable oscillations with a maximum angular velocity of 6 rad/s. Results showed that the IR-ToF proximity sensor was not sensitive to variations of both distance and target color (except for black). Conversely, a relationship between error magnitude and AoI values was found. For AoI equal to 0 , the IR-ToF sensor performed equally well both in static and dynamic acquisitions with a distance mean absolute error <1.5 mm. Errors increased up to 3.6 mm (static) and 11.9 mm (dynamic) for AoI equal to ± 30 , and up to 7.8 mm (static) and 25.6 mm (dynamic) for AoI equal to ± 60 . In addition, the wearable platform was used during a preliminary experiment for the estimation of the inter-foot distance on a single healthy subject while walking. In conclusion, the combination of magneto-inertial unit and IR-ToF technology represents a valuable alternative solution in terms of accuracy, sampling frequency, dimension and power consumption, compared to existing technologies. View Full-Text
Keywords: wearable devices; inertial sensors; time-of-flight; proximity sensors; distance estimation; human movement analysis; step width wearable devices; inertial sensors; time-of-flight; proximity sensors; distance estimation; human movement analysis; step width
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Bertuletti, S.; Cereatti, A.; Comotti, D.; Caldara, M.; Della Croce, U. Static and Dynamic Accuracy of an Innovative Miniaturized Wearable Platform for Short Range Distance Measurements for Human Movement Applications. Sensors 2017, 17, 1492.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top