{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T14:42:53Z","timestamp":1767192173186,"version":"3.48.0"},"reference-count":24,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,30]],"date-time":"2025-12-30T00:00:00Z","timestamp":1767052800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Science and Technology Research and Development Program Project of China Railway Group Limited","award":["2022-Special-09"],"award-info":[{"award-number":["2022-Special-09"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The challenge of insufficient monitoring accuracy in vision-based multi-point displacement measurement of bridges using Unmanned Aerial Vehicles (UAVs) stems from camera motion interference and the limitations in camera performance. Existing methods for UAV motion correction often fall short of achieving the high precision necessary for effective bridge monitoring, and there is a deficiency of high-performance cameras that can function as adaptive sensors. To address these challenges, this paper proposes a UAV vision-based method for multi-point displacement measurement of bridges and introduces a monitoring system that includes a UAV-mounted camera, a computing terminal, and targets. The proposed technique was applied to monitor the dynamic displacements of the Lunzhou Highway Bridge in Qingyuan City, Guangdong Province, China. The research reveals the deformation behavior of the bridge under vehicle traffic loads. Field test results show that the system can accurately measure vertical multi-point displacements across the entire span of the bridge, with monitoring results closely matching those obtained from a Scheimpflug camera. With a root mean square error (RMSE) of less than 0.3 mm, the proposed method provides essential data necessary for bridge displacement monitoring and safety assessments.<\/jats:p>","DOI":"10.3390\/s26010240","type":"journal-article","created":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T14:33:25Z","timestamp":1767191605000},"page":"240","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["UAV Vision-Based Method for Multi-Point Displacement Measurement of Bridges"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-3531-5656","authenticated-orcid":false,"given":"Deyong","family":"Pan","sequence":"first","affiliation":[{"name":"National Engineering Research Center of High-Speed Railway Construction Technology, Changsha 410075, China"},{"name":"Department of Surveying Engineering & Geo-Informatics, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1606-117X","authenticated-orcid":false,"given":"Wujiao","family":"Dai","sequence":"additional","affiliation":[{"name":"Department of Surveying Engineering & Geo-Informatics, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-5196-6419","authenticated-orcid":false,"given":"Lei","family":"Xing","sequence":"additional","affiliation":[{"name":"National Engineering Research Center of High-Speed Railway Construction Technology, Changsha 410075, China"},{"name":"Department of Surveying Engineering & Geo-Informatics, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5133-9691","authenticated-orcid":false,"given":"Zhiwu","family":"Yu","sequence":"additional","affiliation":[{"name":"National Engineering Research Center of High-Speed Railway Construction Technology, Changsha 410075, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Wu","sequence":"additional","affiliation":[{"name":"China Railway Group Limited, Beijing 100039, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2779-2015","authenticated-orcid":false,"given":"Yunsheng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Surveying Engineering & Geo-Informatics, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1016\/j.engstruct.2017.11.018","article-title":"Computer vision for SHM of civil infrastructure: From dynamic response measurement to damage detection\u2014A review","volume":"156","author":"Feng","year":"2018","journal-title":"Eng. 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