Print Email Facebook Twitter A Comprehensive Study on Measurement Accuracy of Distributed Fiber Optic Sensors Embedded within Capillaries of Solid Structures Title A Comprehensive Study on Measurement Accuracy of Distributed Fiber Optic Sensors Embedded within Capillaries of Solid Structures Author Xiao, Y. (TU Delft Structural Integrity & Composites) Rans, C.D. (TU Delft Structural Integrity & Composites) Zarouchas, D. (TU Delft Structural Integrity & Composites) Benedictus, R. (TU Delft Structural Integrity & Composites) Date 2023 Abstract Embedding fiber optic sensors (FOSs) within parts for strain measurement is attracting widespread interest due to its great potential in the field of structural health monitoring (SHM). This work proposes a novel method of embedding FOSs using capillaries within solid structures and investigates fiber positions and orientation uncertainties within capillaries of different sizes and their influences on strain measurement accuracies. To investigate how the fiber positions and orientation variations influence strain measurement accuracy, both analytical and numerical models are utilized to predict strain distributions along embedded fibers at different positions and with different orientations within the specimen. To verify the predictions, a group of specimens made of Aluminum 6082 was prepared, and the specimens in each group had capillaries of 2 mm, 4 mm, and 6 mm diameters, respectively. Fibers were embedded within each specimen using the capillaries. Four-point bending static tests were conducted for each specimen with embedded FOSs, performing in situ strain measurement. Subsequently, the specimens were partitioned into several pieces, and the cross sections were observed to know the real positions of the embedded fiber. Finally, the strain predictions at the real locations of the fiber were compared with the measured strain from the embedded FOSs. The predicted strain distributions as a function of the fiber positions alone and as a function of both the fiber positions and orientations were compared to assess the influence of fiber orientation change. The results from a combination of analytical, numerical, and experimental techniques suggest that the fiber position from the capillary center is the main factor that can influence strain measurement accuracies of embedded FOSs, and potential fiber misalignments within the capillary had a negligible influence. The fiber position-induced measured error increases from 10.5% to 18.5% as the capillary diameter increases from 2 mm to 6 mm. A 2 mm capillary diameter is able to lead to the lowest measurement error in this study and maintains ease of embedding. In addition, it is found that the measured strain always lies within a strain window defined by the strain distribution along capillary boundaries when there are no cracks. This can be further studied for crack detection. Subject fiber optic sensor embeddingstrain measurementstructural health monitoringmeasurement accuracy To reference this document use: http://resolver.tudelft.nl/uuid:4f63adc9-6cd6-43dc-923e-28a9c4a21cb6 DOI https://doi.org/10.3390/s23198083 ISSN 1424-8220 Source Sensors, 23 (19) Part of collection Institutional Repository Document type journal article Rights © 2023 Y. Xiao, C.D. Rans, D. Zarouchas, R. Benedictus Files PDF sensors_23_08083.pdf 2.03 MB Close viewer /islandora/object/uuid:4f63adc9-6cd6-43dc-923e-28a9c4a21cb6/datastream/OBJ/view