Rockwell Automation 5370-CBPK Color CVIM BLISTER-PAK Option - Manual (Page 53)

Chapter 6
Adjusting Blister Windows
6–11
Shape Tolerance
The function of the shape tolerance feature is to accommodate the small
variations that may normally occur in the shape of objects. (Note that for the
purposes of blister packaging inspection, “shape” is a mathematical
expression of the “roundness” of a tablet or capsule.) The
Shape Tol menu
item enables you to control how much shape variation will be allowed in
your own application.
Shape variations encountered during inspection can result from broken or
seriously malformed tablets, shadows, or a tablet’s orientation within a
pocket. Shape tolerance enables you to define what constitutes an acceptable
degree of shape variation in your own application. Shape tolerance is
expressed as a percentage.
The system calculates a shape tolerance value during auto setup. This value
will never be be less than the minimum shape tolerance value that you
entered on the
Configure menu. With the manual shape tolerance
adjustment, however, you may set any value you choose, even one that is
smaller than the minimum shape tolerance value.
When you pick the Shape Tol menu item, a Shape Tol slide bar appears
with two cursors, one each for positive and negative shape adjustments.
When you move one of the cursors up or down, the corresponding shape
tolerance value in the adjacent field changes accordingly over a range of 0%
to 100% (the default tolerance is 10% for the positive and negative
adjustments).
As an example, suppose you select a minus (–) shape tolerance of 15%. This
setting would require the system to accept individual objects whose shape is
up to 15% less “round” than the expected shape.
During cursor adjustment, the outlines of the objects will be displayed.
Objects whose shapes are too round or not round enough (for the current
cursor settings) will be shown in red, while those that are within both shape
tolerance settings will be shown in green.
Minimum Area
The minimum area parameter determines the smallest area of a learned color
that will be treated as an object. It is expressed in pixels, and it can range
from 1 to 1000 pixels (the default value is 25 pixels).
When you pick the Min. Area menu item, a Min. Area slide bar appears.
Use the cursor to select an area value between 1 and 1,000 pixels in
single-pixel increments. During cursor adjustment, the underlying binarized
color image remains onscreen and changes to reflect the changes you make.
The contours of all objects of the selected foreground colors whose areas
equal or exceed the
Min. Area setting will appear in the onscreen image.
Objects that correspond to taught objects will appear in green, while objects
that do not will appear in red. A red “X” will appear over over locations
where an object was expected, but was not found.