Rockwell Automation 5370-CVIM2 Module - Manual (Page 135)

5 Chapter Chapter 5
Pick and Place Function
5–5
When you select the Fixed Center mode, the pick and place operations for an
arc gage have the following functions:
•
Arc ends –– These pick and place points enable you to change the
number of degrees of arc from either end of the arc.
•
Center of arc –– This pick and place point enables you to change the
position of the entire arc within the image field.
•
Arc midpoint –– This pick and place point enables you to change the
radius of the arc while the number of degrees in the arc remains constant.
Figure 5.5 (page 5–6) demonstrates the operation of all pick and place
operations for an arc in the fixed center mode:
•
Example 1: The right end of the arc is picked at point C, dragged in a
circular motion to point C
′, and then placed at point C′, thereby
decreasing the number of degrees in the arc (the arc radius remains the
same).
•
Example 2: The center of the arc is picked at point A, the entire arc is
dragged to point A
′, and is then placed at point A′ (the number of degrees
in the arc and the arc radius are not changed).
•
Example 3: The midpoint of the arc is picked at point D and is dragged
to point D
′, thereby uniformly increasing the radius of the arc (the
number of degrees in the arc remains the same).
When you select the fixed ends mode, the pick and place operations for an
arc have the following functions:
•
Arc ends; center of arc –– These pick and place points have the same
functions in the fixed ends mode as they do in the fixed center mode.
•
Arc midpoint –– This pick and place point enables you to change the
number of degrees of arc and the radius of the arc while the two ends of
the arc remain anchored. This point can move only in a direction that is
perpendicular to a line drawn through the two ends (regardless of their
orientation in the image field); otherwise, the movement is restricted only
by the limits of the image field.
Figure 5.6 (page 5–7) demonstrates the operation of the arc midpoint in the
fixed ends mode (the other pick and place points operate the same as in the
fixed center mode).
•
Example 1: The arc midpoint is picked at point D, dragged upward to
point D
′, and then placed at point D′. In this example, the number of
degrees in the arc decrease, but the radius of the arc increases.
•
Example 2: The arc midpoint is picked at point D, dragged downward to
point D
′, and then placed at point D′. In this example, both the radius of
the arc and the number of degrees in the arc increase.