Denso WINCAPS III, Руководство пользователя

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Chapter 9 Vision Manager
173
Note
What is a model search?
Caution
• Only rectangular windows (angle = 0) qualify as targets.
• The two angle fields are not available when the robot controller does not support angle measure-
ments.
9.2.12.1 Specifying measurement conditions
Target window range to measure.
Search model
This field specifies the search model to use.
Match judgment
This field specifies the minimum score considered a match.
Detection unit
This field specifies the precision for pattern matching coordinates: pixel or subpixel. Specifying subpixel means
that measurements take longer.
Detection count
This field specifies the number of matches expected. Reaching this limit produces normal termination. Other-
wise, the operation times out with an error message. In the latter case, try reducing this setting.
Starting and end angles
These fields specify the angle range for the search. The search looks for matches between the two angles about
the origin.
A search moves standard image data, the search model, over the specified range looking for
matches. (See Figure 1.) A search model consists of image data and reference coordinates (OX,
OY). (See Figure 2.) The match judgment specifies the minimum similarity, the result of a numerical
comparison of the search model and the data at the current position, required to be considered a
match. The precision setting specifies pattern matching alignment: at the pixel level or smaller. Sub-
pixel measurements take longer.
Figure 2 Search model
Search model
OX
OY
Image data
Figure 1
Window
Looking for matches