Rockwell Automation 5370-CVIM2 Module User Manual

Page 56

Chapter

Chapter 3

Image Acquisition Parameters

3–17

4. Enter scale factors –– For the

Absolute

calibration mode only, enter the

appropriate scale factors for each calibration gage.

5. “Pick and place” calibration gages –– For the

Computed

calibration

mode only, position the calibration gages over the workpiece image as
required. (For details, see Chapter 5, Pick and Place Functions.)

6. Set thresholds –– For the

Computed

calibration mode only, set the

threshold cursors to a point where the reference edges are optimized
along the X and Y calibration gages (For details, see Chapter 8,
Threshold, Filters, and Morphology.)

7. Select offsets –– For the

Computed

calibration mode only, select the

two offsets on each calibration gage that correspond to the desired points
between which the calibration measurements must take place.

8. Calibrate –– For the

Computed

calibration mode only, enter X– and

Y–axis dimensions and perform the “learn” functions.

9. Select scale factors –– For the

Absolute

calibration mode only, enter the

scale factors.

Image Setup

In preparation for the calibration procedure, you must acquire a camera
image of a “calibration object,” which can be any object whose dimensions
in the X and Y axes are accurate enough to be used as the basis for
calibrating the tools in your application. If the actual object to be inspected is
not available, you should use an object of similar size to perform the
calibration.

NOTE: You must select the camera resolution that you intend to use in your
application before performing the calibration procedure. If you were to
change the resolution selection after performing the calibration procedure,
you would need to repeat the procedure.

Selecting Calibrate Function

After acquiring a camera image of your calibration object, your next step is
to pick the

button on the appropriate

Camera

setup panel. When

you do, the

Calibrate

panel and the X– and Y–axis calibration “gages”

appear in the image field, as shown in Figure 3.11 (page 3–18).