{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:57:04Z","timestamp":1760241424028,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,10]],"date-time":"2018-02-10T00:00:00Z","timestamp":1518220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a measurement system intended to monitor the usage of walker assistive devices. The goal is to guide the user in the correct use of the device in order to prevent risky situations and maximize comfort. Two risk indicators are defined: one related to force unbalance and the other related to motor incoordination. Force unbalance is measured by load cells attached to the walker legs, while motor incoordination is estimated by synchronizing force measurements with distance data provided by an optical sensor. The measurement system is equipped with a Bluetooth link that enables local supervision on a computer or tablet. Calibration and experimental results are included in the paper.<\/jats:p>","DOI":"10.3390\/s18020540","type":"journal-article","created":{"date-parts":[[2018,2,12]],"date-time":"2018-02-12T10:50:38Z","timestamp":1518432638000},"page":"540","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Monitoring Walker Assistive Devices: A Novel Approach Based on Load Cells and Optical Distance Measurements"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8929-1574","authenticated-orcid":false,"given":"V\u00edtor","family":"Viegas","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 1049-001 Lisboa, Portugal"},{"name":"ESTSet\u00fabal, Instituto Polit\u00e9cnico de Set\u00fabal, 2910-761 Set\u00fabal, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0183-132X","authenticated-orcid":false,"given":"J.","family":"Dias Pereira","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 1049-001 Lisboa, Portugal"},{"name":"ESTSet\u00fabal, Instituto Polit\u00e9cnico de Set\u00fabal, 2910-761 Set\u00fabal, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5055-6347","authenticated-orcid":false,"given":"Octavian","family":"Postolache","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 1049-001 Lisboa, Portugal"},{"name":"ISCTE\u2014Instituto Universit\u00e1rio de Lisboa, 1600-077 Lisboa, Portugal"}]},{"given":"Pedro","family":"Gir\u00e3o","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 1049-001 Lisboa, Portugal"},{"name":"Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,10]]},"reference":[{"key":"ref_1","unstructured":"Werner, C.A. 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