ABSTRACT
For measuring the large machining pieces or structures, stereo vision measurement technology as a non-contact measurement method, for its advantages, fast measurement, real-time and high accuracy, has been extensively studied (Zhang, G.J. 2005). Firstly, gray-code patterns and phase-shifting gratings are generated by a computer, and moreover grating phase self-calibration is necessary (Koninck, T.P. & Van, G.L. 2006). Secondly, a set of stripe encoded patterns is projected onto the measured object by a digital projector and their images are taken by two CCD cameras from dierent angles. The image processing prepares for gray-code and phase decoding. Finally, according to constraint of the epipolar line, gray-code value and phase value, depth information through matching corresponding points is got. The stereo matching process is used to obtain complete measurement information (Chen, M.Y. & Guo, H.W. 2010). So the vision measurement method not only improves the precision, but also reduces the measurement time.
