Next Article in Journal
Multimode Fabry–Perot Interferometer Probe Based on Vernier Effect for Enhanced Temperature Sensing
Next Article in Special Issue
Determination of Effective Mode Selection for Ensuring Spectrum Efficiency with Massive MIMO in IoT Systems
Previous Article in Journal
A Virtual Reality Soldier Simulator with Body Area Networks for Team Training
Previous Article in Special Issue
Low-Cost and Data Anonymised City Traffic Flow Data Collection to Support Intelligent Traffic System
Article Menu
Issue 3 (February-1) cover image

Export Article

Open AccessArticle
Sensors 2019, 19(3), 452;

A Low-Cost Indoor Activity Monitoring System for Detecting Frailty in Older Adults

Information Technologies Institute, Centre for Research and Technology Hellas, Thessaloniki 57001, Greece
Author to whom correspondence should be addressed.
This paper is an extended version of conference paper: Tegou, T.; Kalamaras, I.; Votis, K.; Tzovaras, D. A low-cost room-level indoor localization system with easy setup for medical applications. In Proceedings of the 11th IFIP Wireless and Mobile Networking Conference (WMNC), Prague, Czech Republic, 3–5 September 2018.
Received: 21 December 2018 / Revised: 18 January 2019 / Accepted: 19 January 2019 / Published: 22 January 2019
(This article belongs to the Special Issue Internet of Things and Machine-to-Machine Communication)
PDF [854 KB, uploaded 29 January 2019]


Indoor localization systems have already wide applications mainly for providing localized information and directions. The majority of them focus on commercial applications providing information such us advertisements, guidance and asset tracking. Medical oriented localization systems are uncommon. Given the fact that an individual’s indoor movements can be indicative of his/her clinical status, in this paper we present a low-cost indoor localization system with room-level accuracy used to assess the frailty of older people. We focused on designing a system with easy installation and low cost to be used by non technical staff. The system was installed in older people houses in order to collect data about their indoor localization habits. The collected data were examined in combination with their frailty status, showing a correlation between them. The indoor localization system is based on the processing of Received Signal Strength Indicator (RSSI) measurements by a tracking device, from Bluetooth Beacons, using a fingerprint-based procedure. The system has been tested in realistic settings achieving accuracy above 93% in room estimation. The proposed system was used in 271 houses collecting data for 1–7-day sessions. The evaluation of the collected data using ten-fold cross-validation showed an accuracy of 83% in the classification of a monitored person regarding his/her frailty status (Frail, Pre-frail, Non-frail). View Full-Text
Keywords: indoor localization; Bluetooth beacons; room-level accuracy; frailty level assessment indoor localization; Bluetooth beacons; room-level accuracy; frailty level assessment

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).

Share & Cite This Article

MDPI and ACS Style

Tegou, T.; Kalamaras, I.; Tsipouras, M.; Giannakeas, N.; Votis, K.; Tzovaras, D. A Low-Cost Indoor Activity Monitoring System for Detecting Frailty in Older Adults. Sensors 2019, 19, 452.

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



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