{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,19]],"date-time":"2026-04-19T04:47:29Z","timestamp":1776574049031,"version":"3.51.2"},"reference-count":34,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T00:00:00Z","timestamp":1776384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Open Fund of State Key Laboratory of Offshore Wind Power Equipment and Wind Energy Efficient Utilization","award":["HFQZS2025-14"],"award-info":[{"award-number":["HFQZS2025-14"]}]},{"DOI":"10.13039\/501100007129","name":"Natural Science Foundation of Shandong Province","doi-asserted-by":"crossref","award":["ZR2024ME003"],"award-info":[{"award-number":["ZR2024ME003"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Wind turbine blades are subjected to complex environmental conditions during long-term operation, which may lead to structural degradation and performance loss. To ensure structural integrity, fatigue testing prior to deployment is essential. This paper proposes a vision-based method for measuring the full-cycle breathing deformation of wind turbine blades during fatigue testing. The method captures dynamic image sequences of the blade\u2019s hotspot cross-section using industrial cameras and employs a feature-based template matching approach to reconstruct the three-dimensional coordinates of target points. Through coordinate transformation, the deformation trajectories are obtained, enabling quantitative analysis of the blade\u2019s dynamic responses in both flapwise and edgewise directions. A dedicated hardware\u2013software system was developed and validated through full-scale fatigue experiments. Quantitative comparison with strain gage measurements shows that the proposed method achieves mean absolute deviations of 0.84 mm and 0.93 mm in two independent experiments, respectively, with closely matched deformation trends under typical loading conditions. These results demonstrate that the proposed method can reliably capture the global deformation behavior of the blade with millimeter-level accuracy, while significantly reducing instrumentation complexity compared to conventional contact-based approaches. The proposed method provides an effective and practical solution for full-field dynamic deformation measurement in blade fatigue testing, offering strong potential for structural health monitoring and early damage detection in wind turbine systems.<\/jats:p>","DOI":"10.3390\/jimaging12040174","type":"journal-article","created":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T11:53:46Z","timestamp":1776426826000},"page":"174","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Vision-Based Measurement of Breathing Deformation in Wind Turbine Blade Fatigue Test"],"prefix":"10.3390","volume":"12","author":[{"given":"Xianlong","family":"Wei","sequence":"first","affiliation":[{"name":"Shandong Key Laboratory of Wind Power Equipment Testing, Evaluation and Service Support Technology, Shandong University of Technology, Zibo 255000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6275-9475","authenticated-orcid":false,"given":"Cailin","family":"Li","sequence":"additional","affiliation":[{"name":"Shandong Key Laboratory of Wind Power Equipment Testing, Evaluation and Service Support Technology, Shandong University of Technology, Zibo 255000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhiyong","family":"Wang","sequence":"additional","affiliation":[{"name":"Shandong Key Laboratory of Wind Power Equipment Testing, Evaluation and Service Support Technology, Shandong University of Technology, Zibo 255000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-4644-5923","authenticated-orcid":false,"given":"Zhao","family":"Hai","sequence":"additional","affiliation":[{"name":"Shandong Key Laboratory of Wind Power Equipment Testing, Evaluation and Service Support Technology, Shandong University of Technology, Zibo 255000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinghua","family":"Wang","sequence":"additional","affiliation":[{"name":"Shandong Key Laboratory of Wind Power Equipment Testing, Evaluation and Service Support Technology, Shandong University of Technology, Zibo 255000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leian","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shandong Key Laboratory of Wind Power Equipment Testing, Evaluation and Service Support Technology, Shandong University of Technology, Zibo 255000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Al-Khudairi, O., Hadavinia, H., Little, C., Gillmore, G., Greaves, P., and Dyer, K. 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