Rockwell Automation GMLC Reference Manual - Manual (Page 241)

Publication GMLC-5.2 - November 1999
204 Motion Blocks
Note that if the master axis is not moving, you can achieve this same
effect using another position-lock cam block with a new master reference
position. The phase shift move, however, allows this adjustment to be
made at a controlled rate while the master is moving and the position-lock
cam is executing.
You can use phase shift moves to provide slip compensation for the
master axis when you use a position-lock cam. In such a case, the amount
of slip can be determined using the standard registration capability. A
phase shift Move Axis block can smoothly adjust the position-lock cam
profile by the slip distance.
Rotary Shortest Path Moves
Rotary Shortest Path moves a rotary Axis to the desired absolute position
via the shortest path. It is a special type of absolute move available only
for rotary axes.
!
ATTENTION: Use Rotary Shortest Path moves only
with rotary axes, and never with linear axes.
.
Master Axis Position
Slave Axis Position
Profile Stored
in Cam Tables
Profile After Phase Shift
Move of Slave Axis
Profile After Incremental
Move of Slave Axis