Rockwell Automation 5370-CBPK Color CVIM BLISTER-PAK Option - Manual (Page 15)

Chapter 2
Functional Overview
2–8
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Color –– This error is reported if a blister contains an object whose color
is one of the trained colors but is not the correct color for its position.
•
Oversize –– This error is reported if a blister contains an object whose
area is too large. This might include two tablets that are touching each
other.
•
Position –– This error is reported if a blister contains an object whose
position is too far from the taught position.
•
Undersize –– This error is reported if a blister contains an object whose
area is too small but whose shape is within the set shape tolerances. This
is very similar to the Broken error, and sometimes the system cannot
distinguish between the two because the shape measurement tends to vary
a great deal for small objects.
•
Broken –– This error is reported if a blister contains an object whose area
is too small and whose shape is outside the set shape tolerances.
•
Shape –– This error is reported if a blister contains an object whose area
is within the set area tolerances but whose shape is outside the set shape
tolerance.
•
Missing –– This error is reported if one or more of the objects expected in
the blister is missing.
Detection vs. Classification –– Defect detection refers to the ability to
determine that some type of defect is present, whereas defect classification
refers to the ability to determine exactly what kind of defect exists. The
BLISTER–PAK option will reject any blister in which it detects a defect, but
there are cases where a given defect in a blister may not be classified reliably
because the defect itself is ambiguous, or because of limitations in the image
processing methods used.
For example, consider the case of a tablet that is broken. If the tolerances
have been set properly, the blister containing the broken tablet will be
rejected because the area of the tablet is too small, but the defect may not be
classified as expected. The expected classification of this defect would be
“Broken”, but if the shape tolerances were set widely enough, it may be
classified as “Undersize” because the shape is sufficiently close to the
original shape of the tablet. Also, when a tablet is broken, it’s center may be
shifted far enough within its pocket to be classified as a “Position” error. This
is the correct classification, but not necessarily what an operator might
expect.