{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T17:09:04Z","timestamp":1790788144314,"version":"4.1.0"},"reference-count":44,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,11,16]],"date-time":"2018-11-16T00:00:00Z","timestamp":1542326400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002322","name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior","doi-asserted-by":"publisher","award":["88887.095626\/2015-01"],"award-info":[{"award-number":["88887.095626\/2015-01"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Funda\u00e7\u00e3o Estadual de Amparo \u00e0 Pesquisa do Estado do Esp\u00edrito Santo","award":["72982608"],"award-info":[{"award-number":["72982608"]}]},{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["304192\/2016-3"],"award-info":[{"award-number":["304192\/2016-3"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["310310\/2015-6"],"award-info":[{"award-number":["310310\/2015-6"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BPD\/109458\/2015"],"award-info":[{"award-number":["SFRH\/BPD\/109458\/2015"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UID\/EEA\/50008\/2013"],"award-info":[{"award-number":["UID\/EEA\/50008\/2013"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>We developed a flexible support with embedded polymer optical fiber (POF) sensors for the assessment of human\u2013robot interaction forces. The supports were fabricated with a three-dimensional (3D) printer, where an acrylonitrile butadiene styrene (ABS) rigid structure was used in the region of the support in which the exoskeleton was attached, whereas a thermoplastic polyurethane (TPU) flexible structure was printed in the region where the users placed their legs. In addition, fiber Bragg gratings (FBGs), inscribed in low-loss, cyclic, transparent, optical polymer (CYTOP) using the direct-write, plane-by-plane femtosecond laser inscription method, were embedded in the TPU structure. In this case, a 2-FBG array was embedded in two supports for human\u2013robot interaction force assessment at two points on the users\u2019 legs. Both FBG sensors were characterized with respect to temperature and force; additionally, the creep response of the polymer, where temperature influences the force sensitivity, was analyzed. Following the characterization, a compensation method for the creep and temperature influence was derived, showing relative errors below 4.5%. Such errors were lower than the ones obtained with similar sensors in previously published works. The instrumented support was attached to an exoskeleton for knee rehabilitation exercises, where the human\u2013robot interaction forces were measured in flexion and extension cycles.<\/jats:p>","DOI":"10.3390\/ma11112305","type":"journal-article","created":{"date-parts":[[2018,11,16]],"date-time":"2018-11-16T11:48:31Z","timestamp":1542368911000},"page":"2305","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":84,"title":["Fiber Bragg Gratings in CYTOP Fibers Embedded in a 3D-Printed Flexible Support for Assessment of Human\u2013Robot Interaction Forces"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9075-0619","authenticated-orcid":false,"given":"Arnaldo","family":"Leal-Junior","sequence":"first","affiliation":[{"name":"Graduate Program of Electrical Engineering, Federal University of Esp\u00edrito Santo, Vit\u00f3ria 29075-910, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5912-9138","authenticated-orcid":false,"given":"Antreas","family":"Theodosiou","sequence":"additional","affiliation":[{"name":"Photonics and Optical Sensing Research Laboratory, Cyprus University of Technology, 3036 Limassol, Cyprus"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9657-5076","authenticated-orcid":false,"given":"Camilo","family":"D\u00edaz","sequence":"additional","affiliation":[{"name":"Graduate Program of Electrical Engineering, Federal University of Esp\u00edrito Santo, Vit\u00f3ria 29075-910, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8596-5092","authenticated-orcid":false,"given":"Carlos","family":"Marques","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es and I3N &amp; Physics Department, Campus Universit\u00e1rio de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9009-2425","authenticated-orcid":false,"given":"Maria Jos\u00e9","family":"Pontes","sequence":"additional","affiliation":[{"name":"Graduate Program of Electrical Engineering, Federal University of Esp\u00edrito Santo, Vit\u00f3ria 29075-910, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4541-092X","authenticated-orcid":false,"given":"Kyriacos","family":"Kalli","sequence":"additional","affiliation":[{"name":"Photonics and Optical Sensing Research Laboratory, Cyprus University of Technology, 3036 Limassol, Cyprus"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0687-3967","authenticated-orcid":false,"given":"Anselmo","family":"Frizera-Neto","sequence":"additional","affiliation":[{"name":"Graduate Program of Electrical Engineering, Federal University of Esp\u00edrito Santo, Vit\u00f3ria 29075-910, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,16]]},"reference":[{"key":"ref_1","unstructured":"Fr\u00e9d\u00e9ric, D. 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