| Staging,
sometimes called fixturing, holds the part to be inspected at a precise
location in front of the camera for a Vision Appliance™ to 'see'.
Staging
is required for three reasons:
1.
To ensure that the surface of the part that you want to inspect
is facing the camera. In some cases the 'parts' may be rotated to
inspect multiple surfaces.
2.
To hold the part still for the brief moment required for the camera
to take a picture of the part. If the part moves too much while
the picture is taken, the image may blurr. In some cases the parts
move so slowly that they do not need to be held still for a good
picture. In other cases a 'détente' or other mechanism holds
the part still for a brief moment. Generally, the motion of the
part is 'frozen' by turning the light on very briefly or by using
a high-speed electronic shutter, standard on the ipd recommended
cameras.
3.
To speed up the processing by putting the part in a location known
to the Vision Appliance. All machine vision systems must first search
to find the part in the image, and this takes time. If you can arrange
the staging to always put the part in about the same location, then
the vision system 'knows' where the part is and can find it much
more quickly.
Staging
usually is mechanical. It also usually includes a Part-in-Place
sensor that tells the machine vision system when a part is in front
of the camera. This sensor is usually a simple light source and
photoelectric detector, for example:
Click
on links above to learn more
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