{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T02:29:46Z","timestamp":1773368986488,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,11]],"date-time":"2021-05-11T00:00:00Z","timestamp":1620691200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Agencia Estatal de Investigaci\u00f3n (AEI) - Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)","award":["DPI2017-82930-C2-1-R"],"award-info":[{"award-number":["DPI2017-82930-C2-1-R"]}]},{"name":"Generalitat de Catalunya","award":["2017 SGR 388"],"award-info":[{"award-number":["2017 SGR 388"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Structural health monitoring for offshore wind turbine foundations is paramount to the further development of offshore fixed wind farms. At present time there are a limited number of foundation designs, the jacket type being the preferred one in large water depths. In this work, a jacket-type foundation damage diagnosis strategy is stated. Normally, most or all the available data are of regular operation, thus methods that focus on the data leading to failures end up using only a small subset of the available data. Furthermore, when there is no historical precedent of a type of fault, those methods cannot be used. In addition, offshore wind turbines work under a wide variety of environmental conditions and regions of operation involving unknown input excitation given by the wind and waves. Taking into account the aforementioned difficulties, the stated strategy in this work is based on an autoencoder neural network model and its contribution is two-fold: (i) the proposed strategy is based only on healthy data, and (ii) it works under different operating and environmental conditions based only on the output vibration data gathered by accelerometer sensors. The proposed strategy has been tested through experimental laboratory tests on a scaled model.<\/jats:p>","DOI":"10.3390\/s21103333","type":"journal-article","created":{"date-parts":[[2021,5,11]],"date-time":"2021-05-11T22:53:40Z","timestamp":1620773620000},"page":"3333","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Unsupervised Damage Detection for Offshore Jacket Wind Turbine Foundations Based on an Autoencoder Neural Network"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9539-4222","authenticated-orcid":false,"given":"Maria del Cisne","family":"Feij\u00f3o","sequence":"first","affiliation":[{"name":"Mechatronics Engineering, Faculty of Mechanical Engineering and Production Science (FIMCP), ESPOL Polytechnic University, Escuela Superior Polit\u00e9cnica del Litoral (ESPOL), Campus Gustavo Galindo Km. 30.5 V\u00eda Perimetral, Guayaquil 09-01-5863, Ecuador"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3507-0282","authenticated-orcid":false,"given":"Yovana","family":"Zambrano","sequence":"additional","affiliation":[{"name":"Mechatronics Engineering, Faculty of Mechanical Engineering and Production Science (FIMCP), ESPOL Polytechnic University, Escuela Superior Polit\u00e9cnica del Litoral (ESPOL), Campus Gustavo Galindo Km. 30.5 V\u00eda Perimetral, Guayaquil 09-01-5863, Ecuador"},{"name":"Facultad de Ingenier\u00edas, Universidad ECOTEC, Km. 13.5 V\u00eda a Samborond\u00f3n, Samborond\u00f3n 092302, Ecuador"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4964-6948","authenticated-orcid":false,"given":"Yolanda","family":"Vidal","sequence":"additional","affiliation":[{"name":"Control, Modeling, Identification and Applications (CoDAlab), Department of Mathematics, Escola d\u2019Enginyeria de Barcelona Est (EEBE), Universitat Polit\u00e8cnica de Catalunya (UPC), Campus Diagonal-Bes\u00f3s (CDB), Eduard Maristany, 16, 08019 Barcelona, Spain"},{"name":"Institut de Matem\u00e0tiques de la UPC\u2014BarcelonaTech (IMTech), Pau Gargallo 14, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6322-4608","authenticated-orcid":false,"given":"Christian","family":"Tutiv\u00e9n","sequence":"additional","affiliation":[{"name":"Mechatronics Engineering, Faculty of Mechanical Engineering and Production Science (FIMCP), ESPOL Polytechnic University, Escuela Superior Polit\u00e9cnica del Litoral (ESPOL), Campus Gustavo Galindo Km. 30.5 V\u00eda Perimetral, Guayaquil 09-01-5863, Ecuador"},{"name":"Control, Modeling, Identification and Applications (CoDAlab), Department of Mathematics, Escola d\u2019Enginyeria de Barcelona Est (EEBE), Universitat Polit\u00e8cnica de Catalunya (UPC), Campus Diagonal-Bes\u00f3s (CDB), Eduard Maristany, 16, 08019 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,11]]},"reference":[{"key":"ref_1","unstructured":"Ohlenforst, K. 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