Deformation Measurement of a Railroad Bridge Using a Photogrammetric Board without Control Point Survey

Figure 4

Layout of CP targets, photogrammetric board, and laser reflector for field measurements (a), camera setup, 3D laser tracker, and train entry on the bridge (b). The enlarged view of a laser reflector and a CP target is shown in the lower left corner of the top image. These reflector and target were used for the comparison of displacement accuracy.

(a)

(b)