摘要 |
In one embodiment of the present invention, two banks (22, 24) of fixed array cameras provide tiled stereo images (I1, I2, I3) and electronics assemble the tiled stereo images into a mosaic image. The mosaic image includes height information derived from the two sets stereo images, and is also compensated as a function of reference points in the image to more closely conform to the actual board (10). Preferably, a SAM model is used to locate the reference points. Reconstructed SAM models corresponding to components on the board are applied within a search area where a certain type of component is expected to be found. The best-fit location of the component within the search area, as well as the skew angle and the probability are computed. The best-fit location is the location where the Manhabolis distance and the residual error are optimized. Once the best-fit location is computed, it is compared to tolerances to identify improperly placed components, the absence of components or the like.
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