TY - GEN
T1 - A multiscale multispectral approach to digital image correlation for SHM applications
AU - Mathew, Melvin
AU - Ellenberg, Andrew
AU - Esola, Shane
AU - Bartoli, Ivan
AU - Kontsos, Antonios
PY - 2017
Y1 - 2017
N2 - A novel technique for digital image correlation (DIC) targeting structural health monitoring (SHM) applications is presented. The method uses multispectral imaging enabling simultaneous data acquisition at variable fields of view (FOV). In general, for a given FOV, appropriate speckle sizes have to be a priori defined, limiting the capability of acquiring viable DIC data from variable working distances or with variable accuracy. Furthermore, straightforward application of multiscale DIC patterns that can be seen in the same wavelength of light can cause measurement errors, forcing the use of larger subset sizes and thus reducing the spatial resolution of the deformation measurements. To overcome such limitations, a patterning technique accounting for camera resolution, distance to target, metric-based optimization and variable wavelength is developed. Specifically, patterns are created for two length scales and applied onto a structure. A black on white speckle pattern for far field measurements in addition to an ultraviolet pattern for near field measurements. The patterns were shown to optimally perform at the a priori calculated working distances. The potential of this method for use in SHM applications is discussed.
AB - A novel technique for digital image correlation (DIC) targeting structural health monitoring (SHM) applications is presented. The method uses multispectral imaging enabling simultaneous data acquisition at variable fields of view (FOV). In general, for a given FOV, appropriate speckle sizes have to be a priori defined, limiting the capability of acquiring viable DIC data from variable working distances or with variable accuracy. Furthermore, straightforward application of multiscale DIC patterns that can be seen in the same wavelength of light can cause measurement errors, forcing the use of larger subset sizes and thus reducing the spatial resolution of the deformation measurements. To overcome such limitations, a patterning technique accounting for camera resolution, distance to target, metric-based optimization and variable wavelength is developed. Specifically, patterns are created for two length scales and applied onto a structure. A black on white speckle pattern for far field measurements in addition to an ultraviolet pattern for near field measurements. The patterns were shown to optimally perform at the a priori calculated working distances. The potential of this method for use in SHM applications is discussed.
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U2 - 10.12783/shm2017/13863
DO - 10.12783/shm2017/13863
M3 - Conference contribution
AN - SCOPUS:85032448331
T3 - Structural Health Monitoring 2017: Real-Time Material State Awareness and Data-Driven Safety Assurance - Proceedings of the 11th International Workshop on Structural Health Monitoring, IWSHM 2017
SP - 163
EP - 170
BT - Structural Health Monitoring 2017
A2 - Chang, Fu-Kuo
A2 - Kopsaftopoulos, Fotis
PB - DEStech Publications
T2 - 11th International Workshop on Structural Health Monitoring 2017: Real-Time Material State Awareness and Data-Driven Safety Assurance, IWSHM 2017
Y2 - 12 September 2017 through 14 September 2017
ER -