Rockwell Automation GMLC Reference Manual - Manual (Page 304)

Publication GMLC-5.2 - November 1999
Auto Correction (Configure Cam) 267
Soft Registration
The Soft_Reg_Pos_Master Axis_Registering Axis variable is used as the
registration position for auto-correction if you selected either absolute or
relative as the auto-correction type and the registering axis is not the same
as the master axis.
For example, if you select AXIS0 as the master axis, and AXIS1 as the
registration axis, the Soft_Reg_Pos_AXIS0_AXIS1 variable is used as
the registration position for auto-correction.
Soft registration is not as accurate as hard registration, because the soft
registration variables are sampled at the servo update rate rather than
directly in hardware.
See the System Variables chapter of this manual for more information on
the Registration_Position and Soft_Reg_Pos… variables.
Auto-Correction Speed
The speed that the auto-correction indexer uses to phase shift the slave
axis is proportional to the current speed of the Master Axis. Therefore,
auto-correction occurs faster when the master is moving faster, and
slower when the master is moving slower.
Generally, if the master axis is not moving at all, no auto-correction of the
slave axis occurs. (See: Starting P-camming or Gearing in Using the
Encoder Input Filter for an exception to this general rule.)
If the selected slave axis is cammed to the actual position of the master in
the subsequent Position Lock Cam block, auto-correction speed is
proportional to the actual instantaneous velocity–not the averaged
velocity–of the master axis. Similarly, if the slave axis is cammed to the
command position of the master axis, auto-correction speed is
proportional to the command velocity of the master axis.
The speed used by the auto-correction indexer depends on the magnitude
of the auto-correction distance-to-go, as shown below.