Omron FH-1 series User Manual page 530

Appendices
Search Detection Method
With search processing, there are two types of detection methods: Search by "Correlation (CR)" and
search by "Shape (PT)".
The detection method can be selected by changing the "Rotation" settings for each processing item.
Setting item
CR
PT
Additional Information
Basic selection flow
Does Measurement
object (workpiece)
rotate?
Rotation range of
measurement
object (workpiece)
Search Speed
For processing items to perform search processing such as [Search] and [Classification], you can spec-
ify the search processing speed by through the model parameter items "Stable", "Precise", and/or
"Skipping angle". If the value specified for "Stab." or "Prec." is small or if the value for "Skipping angle"
is large, the processing speed can be increased since the amount of information for the models will be
decreased during the search. In contrast, if the values specified for "Stab." or "Prec." are large or if the
value for "Skipping angle" is small, the processing speed is slow because search is performed without
the amount of model information being reduced. Specify appropriate values for "Stable", "Precise", and
"Skipping angle" according to the measurement conditions.
Value for "Staple" / "Precise": Small
Value for "Skipping angle"
Measurement time: Short
Measurement precision: Low
A - 12
Measurement for locations where there is high correlation (similar areas) between the color of
the model registration image and the input image is performed. Since brightness is normalized
in this operation, changes in brightness do not affect searching for correct positions.
Measurement for locations where there is a high degree of similarity between the shape of the
model registration image and the input image is performed. Since measurement is based on
shape consistency (profile of model), positions can be measured accurately even if portions of
the model are missing in images.
When the rotation angle range is wide (such as full angle), a search that is faster than a "CR"
search can be performed. Note, however, that this method may be less reliable than a "CR"
search if the image has low contrast or blurred edges.
No rotation (CR)
no
yes
Rotation (PT)
narrow
Rotation (CR)
All
: Large
Description
Value for "Staple" / "Precise": Large
Value for "Skipping angle"
Measurement time: Long
Measurement precision: High
Vision System FH/FHV/FZ5 Series User's Manual (Z365)
: Small