Method of optical quality inspection of workpieces

A method for optically inspecting nominally identical workpieces of a circular cross-section with manufacturing tolerances, the method comprising:

• feeding a workpiece to an inspection device;
• applying a simultaneous translatory and rotational movement to the workpiece via the inspection device while illuminating the workpiece;
• repeatedly taking camera images of overlapping areas of the workpiece during the simultaneous translatory and rotational movement as the workpiece moves across a camera window, the camera images consisting of pixels;
• setting workpiece parameters based on size and shape of the workpiece;
• assembling a composite image from the camera images based on the workpiece parameters;
• determining numerical brightness scores of the workpiece from the composite image;
• comparing the determined numerical brightness scores with known numerical brightness scores;
• assigning a discrepancy score representative of a deviation of the determined numerical brightness scores of the workpiece from the known numerical brightness scores;
• setting a discrepancy score threshold;
• determining that the workpiece passes inspection upon determining that the discrepancy score is below the discrepancy score threshold;
• and
• determining that the workpiece fails the inspection upon determining that the discrepancy score is above the discrepancy score threshold.