User's Manual

Industry Automation and Drive Technologies - SCE
TIA Training Document Page 36 of 47 Module
E12
Status: 01/2010 Vision Sensor Shape Check with SIMATIC S7-300F 2PN/DP and VS120
Click on the button Set up.
Here, we specify the parameters for image pickup and image evaluation.
To create patterns that can be recognized, edges -that is, the transition from light to dark or vice
versa- of the image are used. Although the algorithm extracts the edges automatically, the user has
to provide for an image rich in contrasts through optimum exposure; i.e., to generate models that are
recognizable, creating an image that is rich in contrasts through optimum exposure is a precondition.
Automatic exposure time should be selected only if the object to be checked is not moving.
Selecting the accuracy is based on the size of the search ranges and on the detectable changes of
the object to be checked. Parts in the image are searched for pyramidically.
We start with a rough search with low resolution, and conclude with a detail search with a high
resolution.
The accuracy influences the rough and detailed search.
The higher the checking accuracy, the longer the evaluation takes.
Additional information is provided in Chapter 4 of the operating instructions
"Image Processing System Vision Sensor SIMATIC VS120“.