Rockwell Automation 5370-CVIM2 Module - Manual (Page 166)

5 Chapter Chapter 6
Reference Tools
6–7
Y then X
The Y then X reference line operation consists of two reference lines, one
that lies along the vertical (Y) axis of the image field, and one that lies along
the horizontal (X) axis. This operation is appropriate in applications where
workpiece shift is expected in both the X–axis and the Y–axis, but with more
shift occurring along the Y–axis. (No workpiece rotation is expected.)
In operation, the Y then X reference line operation evaluates the Y–axis first
to determine the Y–axis shift. It applies Y–axis shift compensation to the
X–axis before evaluating the X–axis.
Figure 6.6 illustrates the Y then X reference line operation detecting Y–axis
workpiece shift, applying Y–axis shift to the X–axis, then detecting X–axis
shift in the same workpiece and applying the combined X–Y shift to the
associated window.
Figure 6.6 Example: Using a Y Then X Reference Line Operation
Workpiece:
nominal position
Window: with X–
and Y–axis shift
compensation applied
Window:
original position
X–axis
reference line
Y–axis
reference line
Y–axis
workpiece
shift
X–axis with Y–axis
shift compensation
applied
X–axis
workpiece
shift
Y–axis
reference line
Workpiece:
position after shift
INSPECTED
POSITION
NOMINAL
POSITION