Rockwell Automation 5370-CVIM2 Module - Manual (Page 394)

Chapter 7
Inspection Tools
7–156
Here is a brief description of each profile tool operation:
•
Position –– This operation identifies the location (the X or Y coordinate)
of the selected feature in the image. The location result depends on the
direction of the profile tool’s operation; for example, when the selected
Direction is “ X ,” the location result will be the X coordinate of the
feature. This is the default operation.
•
Distance –– This operation measures the distance, in pixels, between two
points in the profile image, identified as “Feature A” and “Feature B” on
the profile display.
•
FG Objects –– This operation counts the number of foreground objects,
which are the areas in the profile image that are “above” the threshold
setting.
•
BG Objects –– This operation counts the number of background objects,
which are the areas in the profile image that are “below” the threshold
setting.
•
Edges –– This operation counts the number of edges in the profile image.
(Edges are located at points where the profile display intersects the
threshold display.)
Position
This operation configures a profile tool to locate an object along either the
X–axis or the Y–axis of the image, according to the selection in the
Direction field. Position is the default operation.
The position operation is similar to the position operations for a gage tool, in
the sense that they both return the X or Y coordinate of a selected feature or
“edge” on an object. The main difference is that a gage tool identifies objects
on the basis of a binary or gray scale threshold setting, while a profile tool
identifies objects on the basis of where the profile image crosses the
threshold.
When the X direction is selected, the position operation returns the absolute
horizontal position, in pixels, of a specified feature. The X position is
reported in pixels, with the origin (0 coordinate) being the left boundary of
the image.
Figure 7.128 (page 7–157) illustrates a profile tool using the position
operation in the X direction.
In this example, the specified feature on the profile display corresponds to
the left edge of a connector pin, and it is identified as “offset 1.0” in the
Feature selection panel. In the tool edit panel, the X–axis position of this
feature is shown to be 129.553 pixels from the left boundary of the image
field. (Note: The
Feature selection panel is described in detail in the
Feature Selection Functions section on page 7–164.)