Content By David H. Parker

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By: David H. Parker

Electronic distance measurement (EDM) instruments, such as laser trackers, total stations, and handheld laser distance meters, have been used in a limited number of nondestructive testing (NDT) and structural health monitoring (SHM) applications attempting to measure bridge deflections and vibrations. However, a survey of the literature reveals that, by far, most attempts have been by measuring elevation angles with robotic total stations.