Multiscale Deformation Measurements Leveraging Tailorable and Multispectral Speckle Patterns

摘要

Remote measurements using images are particularly useful in structural health monitoring cases in which the installation of contact sensors is difficult. Some limitations, though, associated with photogrammetry-type optical metrology involve the application of speckle patterns, which become even more important with variable working distance or when the required resolution and sensitivity are not a priori known. In this context, multispectral sensing combined with tailored speckle patterns can circumvent some of the challenges of acquiring data at different working distances. The present invention uses multispectral imaging combined controlled generation of speckle patterns to demonstrate an approach for remote sensing related to deformation measurements at the structural level. To demonstrate this approach, two speckle patterns were designed for measurements at specified working distances. The results show that the spectral specific reflectivity of the speckle patterns allow for spatial overlay without affecting imaging within either spectral range considered, which results in the extraction of multiscale deformation measurements.