Patent ID: 7570794

Claim:
Method to operate a vision system to evaluate a machined surface of a cast-metal component, comprising: acquiring from the vision system an original pixelated image of the machined surface, wherein each pixel comprises a digitized representation of a portion of the machined surface; identifying known design surface features in the original pixelated image, based upon predetermined criteria; orienting and scaling the original pixelated image of the machined surface to an XY coordinate system, based upon the known design surface features; generating an inverted digital image of the machined surface; generating a comparison image of the machined surface, comprising eliminating the known design surface features from the inverted digital image; comparing each pixel of the inverted digital image with a correspondingly located pixel of the comparison image, said location based upon the pixelated image oriented and scaled to the XY coordinate system; identifying any surface feature common to the inverted digital image and the comparison image; analyzing statistically each identified surface feature common to both images for conformance to a threshold; and, identifying a defect as any identified surface feature common to both images which exceeds the threshold.