{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T05:44:09Z","timestamp":1775454249843,"version":"3.50.1"},"reference-count":70,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,4]],"date-time":"2026-04-04T00:00:00Z","timestamp":1775260800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>This paper presents a low-cost, lightweight wearable sensing module for real-time multi-degree-of-freedom motion analysis, which is validated using ankle movements from a representative case study. The system is based on a compact inertial measurement unit integrated into a custom-made enclosure and employs Kalman filter-based sensor fusion to estimate three-dimensional joint orientation. An experimental campaign involving sixteen healthy participants was conducted, and measurements were compared against a gold-standard optical motion capture system, Optitrack V120 Trio. Ankle kinematics were analysed across all anatomical planes, including dorsiflexion\/plantarflexion, inversion\/eversion, and adduction\/abduction. Quantitative metrics, including cosine similarity consistently above 0.98 across all movements and root mean square error within 4\u00b0 on average, demonstrate strong agreement between the angular measuring device and motion capture data, with errors remaining within clinically acceptable limits. The results confirm the feasibility of the proposed system as a reliable, portable, and affordable alternative to laboratory-based measurement technologies. Beyond ankle assessment, the sensing approach is applicable to a wide range of motion-assistive and rehabilitation systems, supporting continuous monitoring, personalised therapy, and future integration into intelligent wearable devices.<\/jats:p>","DOI":"10.3390\/robotics15040076","type":"journal-article","created":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T04:10:27Z","timestamp":1775448627000},"page":"76","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Comparative Study of a Real-Time Ankle Mobility Monitoring Wearable System"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-0787-3448","authenticated-orcid":false,"given":"Giovanni","family":"Mastrangelo","sequence":"first","affiliation":[{"name":"Laboratory of Robot Mechatronics (LARM<sup>2<\/sup>), Department of Industrial Engineering, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6874-2508","authenticated-orcid":false,"given":"Betsy Dayana Marcela","family":"Chaparro Rico","sequence":"additional","affiliation":[{"name":"Intelligent Robotics Group, Department of Computer Science, Faculty of Science and Engineering, Swansea University, Swansea SA1 8EN, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8825-8983","authenticated-orcid":false,"given":"Matteo","family":"Russo","sequence":"additional","affiliation":[{"name":"Laboratory of Robot Mechatronics (LARM<sup>2<\/sup>), Department of Industrial Engineering, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9388-4391","authenticated-orcid":false,"given":"Marco","family":"Ceccarelli","sequence":"additional","affiliation":[{"name":"Laboratory of Robot Mechatronics (LARM<sup>2<\/sup>), Department of Industrial Engineering, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5602-1519","authenticated-orcid":false,"given":"Daniele","family":"Cafolla","sequence":"additional","affiliation":[{"name":"Intelligent Robotics Group, Department of Computer Science, Faculty of Science and Engineering, Swansea University, Swansea SA1 8EN, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4186","DOI":"10.1017\/S0263574724001528","article-title":"Challenges in service robot devices for elderly motion assistance","volume":"42","author":"Ceccarelli","year":"2024","journal-title":"Robotica"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1186\/s12984-016-0162-5","article-title":"Powered robotic exoskeletons in post-stroke rehabilitation of gait: A scoping review","volume":"13","author":"Louie","year":"2016","journal-title":"J. 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