Rockwell Automation 5370-CVIM2 Module - Manual (Page 254)

Chapter 7
Inspection Tools
7–16
NOTE: The following gage operations apply only to arc gages. For
information about the pick and place operations that are unique to arc gages,
refer to Chapter 5, Pick and Place Functions, under the Arc Gages heading
on page 5–3.
Theta (Arc and Circle Gage Only)
This gage operation is available for arc and circle gages using either the
binary gaging mode or the gray scale gaging mode. The theta operation
measures the absolute angle of arc defined by an edge on an arc gage. The
angle is reported in degrees relative to the X–axis (at the 0
° position) and
measuring clockwise from the origin.
Figure 7.16 shows an example of an arc gage using the theta operation to
measure the angle formed by a radius of a circle and the X–axis.
Figure 7.16 Example: Measuring the Theta Angle
0 ° axis
X–axis 0
°
Note that the measured angle for any edge is independent of the number of
degrees of arc of the arc gage, or whether the search direction is head–to–tail
or tail–to–head.
Wedge Angle (Arc and Circle Gage Only)
This gage operation is available for arc and circle gages using either the
binary gaging mode or the gray scale gaging mode. The wedge angle
operation measures the relative angle of arc between two edges on the arc
gage. The value is reported in degrees and is measured clockwise from the
first edge (feature A) and the second edge (feature B).