The need to simultaneously measure sheet metal geometry and strain arises during research, die tryout, statistical process control production part approval, or in response to manufacturing exceptions. Several optical systems have been developed for strain and geometry measurement of small specimens. Large scale geometric measurement is possible using coordinate measuring machines equipped with touch probes. This Technical Brief summarizes the extension of these methods using three dimensional gray level point clouds obtained from either laser digitizers or an in-house developed stereo vision system.
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