Danaher Motion
06/2005
Single-Axis Motion
4.2.3. Registration
Registration applications are those that start motion and then modify the
profile, based on a subsequent event. These applications generally involve
discrete product processing, such as are common in the packaging, printing
and converting industries. The event is usually generated by sensing a
position on the product being processed (usually a mark is printed on the
product and detected by an optical sensor). The mark is normally referred to
as a registration mark.
A common registration application is cutting a product package, such as a
bag or label from a web (reel). The web is printed with many copies of the
product package. The controller begins to unwind the product package from
the web. During this motion, the controller waits for a registration mark to be
detected. After the mark is detected, the profile is modified, based on the
position at which the mark was detected. Commonly, the profile comes to
rest a fixed distance after the mark position where the package can be cut.
There are numerous variations of this type of application. The key element is
that the end position of the move cannot be calculated until after the move
starts. This requires that the profile be started and then modified on-the-fly.
The MC combines the ability to change the position end points on-the-fly and
the ability to command the SERVO
STAR
drive to capture a position.
Registration is similar to homing except that in homing you go back to the
mark, but in registration you go forward to a fixed distance after the mark.
The following example shows a typical registration example:
Program
'Prepare SERVOSTAR drive to capture
VCruise = 3000
Cycle:
Move FeedAxis 50
'wait for capture
Move FeedAxis [capture position] + 10 StartType=IMMED
End Program
This example generates the next profile.
The move starts and the registration mark is detected about 40% of the way
to the end. After a small amount of processing time, the second move is
loaded over the current move. The axis comes to rest at a fixed offset after
the registration mark.
M-SS-005-03 Rev
E
101