FCM_User Reference Manual.pdf.pdf - 第215页
4022 591 960 82 Us er Reference Man ual 02.02 FC M Multif lex 6-23 Pr oduc t Ch ang e Ov er NOTE: It is poss ible - but not recommended - to set the >/LJKW /HYHO @ an d >7KUHVKROG@ manually as in nearly all cases …

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User Reference Manual 4022 591 96082
6-22 FCM Multiflex 02.02
you can change the algorithm, the one with the highest Confidence Level is
preferred. Select [Ok] to set the new settings or [Cancel] to discard the new
settings.
The results of the automatic teaching can be tested by selecting [Measure].
■ Select
[Teach]
■ Select [Measure]
The test results of the measurement will be shown in the box.
NOTE: Normally the automatic teach function will supply the correct values!
!
WARNING: IF FIRST TEACHING DOESN’T GET THE FIDUCIAL IN THE CENTRE OF THE
SCREEN, FIRST CHECK THE CORRECTNESS OF THE CARRIER SET MOUNTING
(WELL FASTENED? NO CLEARANCE?) AND/OR THE ACTION SPEC FIDUCIAL
COORDINATES CONCERNED.
■ Select [Store] to store the taught data in the current data base
■ Select
[Next Fiducial] to go to the next fiducial to be measured
■ Select
[Type...] to change the type of fiducial to be taught
Light Level and Threshold
■ Select [Light Level and Threshold]
For a reliable fiducial detection, the light level and threshold must have been
set.
The threshold value is used by the binary algorithm to transform a grey level
image into a black & white image.
The threshold value is used by the interpolation algorithm to analyze grey level
transitions in the image.
SCREEN 6-14

4022 591 96082 User Reference Manual
02.02 FCM Multiflex 6-23
Product Change Over
NOTE: It is possible - but not recommended - to set the >/LJKW /HYHO@ and
>7KUHVKROG@ manually as in nearly all cases the correct settings will be
supplied automatically by selecting >7HDFK@.
Before setting the threshold value for the binary algorithm, first the grey levels of
the fiducial and its background have to be determined. Proceed as follows:
■ Select
[Measure Greylevel] to determine the grey levels of the fiducial and its
background
SCREEN 6-15
■ Select with the tracker ball and the sliders a spot with a representative grey level
in the fiducial and one in the background
SCREEN 6-16

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User Reference Manual 4022 591 96082
6-24 FCM Multiflex 02.02
■ Read the [Average grey level in area] value for fiducial and its background
■ Use a value in between as the
[Threshold] level to be set
NOTE: In demanding situations some try-outs may be required, e.g. reset camer-
aposition (if background is out of view), selection of another fiducial etc.
Algorithm
There are 2 options for the fiducial detection algorithm:
■ Select
[Algorithm]
SCREEN 6-17
NOTE: Please notice that the optimum algorithm is calculated by the automatic
teach function! So there is no point for changing this setting manually.
NOTE: The quicker binary algorithm requires a good image, no spots and damages.
If you are in doubt, make some trial measurements.
The following parameters are effected by the selected algorithm:
• [Threshold]
• [Tolerance]
• [Polarity]
• [Smallest Enclosing Rectangle]
• [Area of Interest]
• [Area of Fiducial]
This is indicated in the description of the parameter concerned.
binary quick but less reliable
interpolation slower but more reliable