{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T04:50:04Z","timestamp":1773636604244,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,7,7]],"date-time":"2023-07-07T00:00:00Z","timestamp":1688688000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FRA Consolidated Rail Infrastructure and Safety Improvements (CRISI) Program"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Remote and real-time displacement measurements are crucial for a successful bridge health monitoring program. Researchers have attempted to monitor the deformation of bridges using remote sensing techniques such as an accelerometer when a static reference frame is not available. However, errors accumulate throughout the double-integration process, significantly reducing the reliability and accuracy of the displacement measurements. To obtain accurate reference-free bridge displacement measurements, this paper aims to develop a real-time computing algorithm based on hybrid sensor data fusion and implement the algorithm via smart sensing technology. By combining the accelerometer and strain gauge measurements in real time, the proposed algorithm can overcome the limitations of the existing methods (such as integration errors, sensor drifts, and environmental disturbances) and provide real-time pseud-static and dynamic displacement measurements of bridges under loads. A wireless sensor, SmartRock, containing multiple sensing units (i.e., triaxial accelerometer and strain gauges) and a Micro Controlling Unit (MCU) were utilized for remote data acquisition and signal processing. A remote sensing system (with SmartRocks, an antenna, an industrial computer, a Wi-Fi hotspot, etc.) was deployed, and a laboratory truss bridge experiment was conducted to demonstrate the implementation of the algorithm. The results show that the proposed algorithm can estimate a bridge displacement with sufficient accuracy, and the remote system is capable of the real-time monitoring of bridge deformations compared to using only one type of sensor. This research represents a significant advancement in the field of bridge displacement monitoring, offering a reliable and reference-free approach for remote and real-time measurements.<\/jats:p>","DOI":"10.3390\/rs15133444","type":"journal-article","created":{"date-parts":[[2023,7,10]],"date-time":"2023-07-10T00:47:35Z","timestamp":1688950055000},"page":"3444","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Sensing Mechanism and Real-Time Bridge Displacement Monitoring for a Laboratory Truss Bridge Using Hybrid Data Fusion"],"prefix":"10.3390","volume":"15","author":[{"given":"Kun","family":"Zeng","sequence":"first","affiliation":[{"name":"Department of Geotechnical Engineering, College of Civil Engineering, Tongji University, Shanghai 200092, China"},{"name":"Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16803, USA"}]},{"given":"Sheng","family":"Zeng","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Chongqing Jiaotong University, Chongqing 400074, China"}]},{"given":"Hai","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Rail Transportation Engineering, Penn State Altoona, Altoona, PA 16601, USA"}]},{"given":"Tong","family":"Qiu","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16803, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5718-722X","authenticated-orcid":false,"given":"Shihui","family":"Shen","sequence":"additional","affiliation":[{"name":"Department of Rail Transportation Engineering, Penn State Altoona, Altoona, PA 16601, USA"}]},{"given":"Hui","family":"Wang","sequence":"additional","affiliation":[{"name":"Zhengzhou Road & Bridge Construction Investment Group Co., Ltd., Zhengzhou 450000, China"}]},{"given":"Songkai","family":"Feng","sequence":"additional","affiliation":[{"name":"Zhengzhou Road & Bridge Construction Investment Group Co., Ltd., Zhengzhou 450000, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5891-103X","authenticated-orcid":false,"given":"Cheng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16803, USA"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1007\/s11340-006-6124-2","article-title":"Real-time displacement measurement of a flexible bridge using digital image processing techniques","volume":"46","author":"Lee","year":"2006","journal-title":"Exp. 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