Online multidimensional measurement of complex workpieces based on stereo computer vision

This paper presents a new way for online multi-dimensional measurement of complex workpieces, which is based on the stereo computer vision. We also advanced a new algorithm to obtain the disparity image for the image matching. In this algorithm we combine the pyramid image-matching strategy and the means of dynamic programming, and then apply the sub-pixel matching. Thus, the characteristic lines and circles of the measured workpiece are reconstructed in the image space. Using Hough transform, we obtain the information of the circles and the lines in the measurand. Then we get the sizes required. Compared with those obtained by CMM, the results have quite high accuracy.