{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T03:45:08Z","timestamp":1775792708437,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,2,23]],"date-time":"2022-02-23T00:00:00Z","timestamp":1645574400000},"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>Timely and reliable identification of control phases is functional to the control of a powered robotic lower-limb prosthesis. This study presents a commercial energy-store-and-release foot prosthesis instrumented with a multimodal sensory system comprising optoelectronic pressure sensors (PS) and IMU. The performance was verified with eight healthy participants, comparing signals processed by two different algorithms, based on PS and IMU, respectively, for real-time detection of heel strike (HS) and toe-off (TO) events and an estimate of relevant biomechanical variables such as vertical ground reaction force (vGRF) and center of pressure along the sagittal axis (CoPy). The performance of both algorithms was benchmarked against a force platform and a marker-based stereophotogrammetric motion capture system. HS and TO were estimated with a time error lower than 0.100 s for both the algorithms, sufficient for the control of a lower-limb robotic prosthesis. Finally, the CoPy computed from the PS showed a Pearson correlation coefficient of 0.97 (0.02) with the same variable computed through the force platform.<\/jats:p>","DOI":"10.3390\/s22051731","type":"journal-article","created":{"date-parts":[[2022,2,24]],"date-time":"2022-02-24T00:53:26Z","timestamp":1645664006000},"page":"1731","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["A Multimodal Sensory Apparatus for Robotic Prosthetic Feet Combining Optoelectronic Pressure Transducers and IMU"],"prefix":"10.3390","volume":"22","author":[{"given":"Tommaso","family":"Fiumalbi","sequence":"first","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"}]},{"given":"Elena","family":"Martini","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"}]},{"given":"Vito","family":"Papapicco","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"}]},{"given":"Filippo","family":"Dell\u2019Agnello","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4524-7029","authenticated-orcid":false,"given":"Alessandro","family":"Mazzarini","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"}]},{"given":"Andrea","family":"Baldoni","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0732-8378","authenticated-orcid":false,"given":"Emanuele","family":"Gruppioni","sequence":"additional","affiliation":[{"name":"Centro Protesi INAIL, Istituto Nazionale per l\u2019Assicurazione Contro gli Infortuni sul Lavoro, 40054 Bologna, Italy"}]},{"given":"Simona","family":"Crea","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"IRCCS Fondazione Don Carlo Gnocchi, 20162 Milan, Italy"}]},{"given":"Nicola","family":"Vitiello","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"IRCCS Fondazione Don Carlo Gnocchi, 20162 Milan, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"422","DOI":"10.1016\/j.apmr.2007.11.005","article-title":"Estimating the Prevalence of Limb Loss in the United States: 2005 to 2050","volume":"89","author":"MacKenzie","year":"2008","journal-title":"Arch. 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