Deformation measurement by a new FAST-vision a

摘要

Abstract: A new approach for photogrammetric measurement of deformation based on the known proposals of Facet Stereo Vision (Wrobel, Ebner, et al.) is presented. The approach of FAST-vision defines independent values of the object coordinate Z and the optical density D at discrete positions X, Y in the object space. These unknowns can be determined by a least square matching procedure together with the parameters of the interior and exterior orientation of the camera. In our approach the unknown displacement can be calculated together with the other unknowns of the FAST-Vision approach. Only gray values of the digital images are considered as observations. Therefore a number of different loading states can be determined in one least square adjustment process. This approach has been adapted to very small object surfaces ($APEQ 15 * 15 mm). The arrangement consists of two CCD- cameras (Kodak-Videk-Megaplus), which were fitted at a mechanical testing machine. The procedure is demonstrated by an example from fracture mechanics. !3