Rockwell Automation GMLC Reference Manual - Manual (Page 516)

Publication GMLC-5.2 - November 1999
479
In the Tag Explorer, select both Axis System Variables and the desired
axis, then select Strobed_Position from the Tag Window scrolling list. See
the figure in Axis System Variables and Command Position earlier in this
section for more information on the relationship between command
position, actual position, and position error.
Strobed positions are useful to correct for any motion occurring between
the detection of an event and the action initiated by the event. For
instance, in coil winding applications, strobed position can be used in an
expression to compensate for overshooting the end of the bobbin before
the gearing direction is reversed. If you know the position of the coil
when the gearing direction was supposed to change, and the position at
which it actually changed (the strobed position), you can calculate the
amount of overshoot, and use it to correct the position of the wire guide
relative to the bobbin.
Registration Position
Registration_Position is the absolute position of a physical or virtual axis
(in the position units of that axis) at the occurrence of the most recent
registration event for that axis. In the Tag Explorer, select both Axis
System Variables and the desired axis, then select Registration_Position
in the Tag Window.
The figure below shows how the registration position is latched by the
registration input when a registration event occurs.
Registration
Input Registration
Position
Registration
Latch
Encoder
Counter Encoder