{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:40:47Z","timestamp":1760218847763,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2014,12,19]],"date-time":"2014-12-19T00:00:00Z","timestamp":1418947200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010096","name":"SEP","doi-asserted-by":"publisher","award":["PROMEP\/103.5\/12\/8045"],"award-info":[{"award-number":["PROMEP\/103.5\/12\/8045"]}],"id":[{"id":"10.13039\/100010096","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013704","name":"CONACYT","doi-asserted-by":"publisher","award":["289377","281517","289473","166361"],"award-info":[{"award-number":["289377","281517","289473","166361"]}],"id":[{"id":"10.13039\/501100013704","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The implementation of signal filters in a real-time form requires a tradeoff between computation resources and the system performance. Therefore, taking advantage of low lag response and the reduced consumption of resources, in this article, the Recursive Least Square (RLS) algorithm is used to filter a signal acquired from a fiber-optics-based sensor. In particular, a Long-Period Fiber Grating (LPFG) sensor is used to measure the bending movement of a finger. After that, the Gaussian Mixture Model (GMM) technique allows us to classify the corresponding finger position along the motion range. For these measures to help in the development of an autonomous robotic hand, the proposed technique can be straightforwardly implemented on real time platforms such as Field Programmable Gate Array (FPGA) or Digital Signal Processors (DSP). Different angle measurements of the finger\u2019s motion are carried out by the prototype and a detailed analysis of the system performance is presented.<\/jats:p>","DOI":"10.3390\/s141224483","type":"journal-article","created":{"date-parts":[[2014,12,19]],"date-time":"2014-12-19T10:50:22Z","timestamp":1418986222000},"page":"24483-24501","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["An Architecture for Measuring Joint Angles Using a Long Period Fiber Grating-Based Sensor"],"prefix":"10.3390","volume":"14","author":[{"given":"Carlos","family":"Perez-Ramirez","sequence":"first","affiliation":[{"name":"Laboratorio de Procesamiento Digital de Se\u00f1ales, Departamento de Electr\u00f3nica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago Km. 3.5 + 1.8 Km., Salamanca 36885, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dora","family":"Almanza-Ojeda","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Rob\u00f3tica, Universidad Polit\u00e9cnica de Guanajuato, Av. Universidad Norte SN, Comunidad Juan Alonso, Cortazar 38483, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jesus","family":"Guerrero-Tavares","sequence":"additional","affiliation":[{"name":"Laboratorio de Optoelectr\u00f3nica, Departamento de Electr\u00f3nica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago Km. 3.5 + 1.8 Km., Salamanca 36885, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francisco","family":"Mendoza-Galindo","sequence":"additional","affiliation":[{"name":"Laboratorio de Procesamiento Digital de Se\u00f1ales, Departamento de Electr\u00f3nica, DICIS, Universidad de Guanajuato, Carr. 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