Automatic deformation measurement with a digital still video camera

This paper shows the application of a digital still video camera to the measurement of deformations occuring during the dehydration process of concrete parts over several months. A block of 28 images, arranged in two convergent stripes, was recorded with a Kodak DCS200 in six epochs. Using signalized points and a set of coded targets, the dataflow in repeated measurements could be widely automated. The camera was calibrated for each epoch individually by photogrammetric self-calibration techniques. An externally verified precision of the deformation vectors of 3/3/6 micron in X/Y/Z coordinate direction was achieved over an object space with a largest dimension of 80 cm, proving the high accuracy potential of a digital still video camera applied to relative 3-D measurements.