Reference Manual
Chapter
4
IVC-2D
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SICK AG • Advanced Industrial Sensors • www.sick.com • All rights reserved
135
Circular
Check Circular Shape
This tool checks the shape of a circular contour for defects. The contour for the shape
check must be generated by either the ‘External Perimeter’ or ‘Internal Perimeter’ tool. Due
to the fact that the tool is designed for circular shaped contours the considered contour
should have a circular shape as well.
Defects are classified in two different categories: spikes and dents (see the figure below).
It is possible to detect either spikes or dents or both of them. Basically the algorithm
calculates for a contour pixel the distance from the center of gravity and compares this
result with the distance to the center of gravity of other contour pixels. Input parameter
Sensitivity
defines the accepted variation in distance.
Average pixels
are the number of
pixels whose distances are averaged for the comparison.
The evaluation starts at the point on the contour which is defined in the tool External or
Internal perimeter. Beginning at this point the algorithm follows the contour counterclockwi-
se until the first defect is found. If a defect is detected the tool terminates and returns the
coordinates of the first found defect.
Figure – Example for the two categories of defects on an external circular shape:
a) category dent, b) category spike.
Input Parameters
01 = Perimeter definition step
Select the desired contour for the shape check.
Refer to step program which executes either
Internal perimeter or External perimeter.
02 = Type
Set which shape defects that will be detected.
-1
detect dents only
1
detect
spikes
only
0
detect both.
03 = Sensitivity
Sensitivity to detect shape defects.
Range: 0 .. 100.
0 is most sensitive to defects.
04 = Scan interval
The interval between scanned pixels for compari-
son.
05 = Average pixels
Number of pixels to calculate mean distance from
center of gravity.
06 = Destination bank
Image bank to display image and the point with
the first defect.
Returned Values
01 = Transition flag
0
at least one defect was found
-1
no defect was found
02 = X transition
X coordinate of the first found defect.
03 = Y transition
Y coordinate of the first found defect.
a)
b)