Aerotech UNIDEX 600 Series, User Manual

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Parameters U600 User’s Guide
C-30
Aerotech, Inc.
Version 1.4
MASTERPOS.X = POSCMD.Y ; where X is the slave, Y is the master
This should only be set while the master axis and slave axes are not synchronized, or you
may jerk the slave axis.
In a related point, if the master is a rotational axis you should also set the MASTERLEN
axis parameter to the number of counts per rotation, to avoid MASTERPOS overruns.
C.2.61.1. Master Axis Selection
At least two axes are involved in any master/slave motion, the axis whose motion is
dependent upon the other, is the slave axis and a user specified master axis is used to
command the slave. The master axis may be an existing axis, a handwheel, or a virtual
axis. If you want to base axes motion on another axes motion, clearly the master axes
needs to be a real axes, or all slave motion must be pre-computed against time, with a
virtual axis being the master, commanded at a constant velocity, synchronizing all slave
axes. However, if all you want to do is provide a velocity or distance profile to a single
axis, then your master should be configured as virtual.
It is recommended, where possible, that you select your axes such that the master axis has
a smaller axis index then the slave. For example, X as the master and Y as the slave axis
is preferred, than vise versa. This is because when the master axis has a higher axis index
than the slave, and the master axis is not moving at a constant speed, a slight mis-tracking
will exist. The MASTERPOS read by the slave is not equal to the position of the master.
This “following error” is equal to the acceleration of the master (in cnts/msec squared)
and is usually only a few counts.
Finally, if the master is a rotary Type axis, you must consider setting the MASTERLEN
axis parameter to avoid 32-bit overruns of the MASTERPOS.
C.2.62. MASTERRES
The master resolver axis parameter is the current resolver position (0-65535) for the axes
master axis, if the axis has been configured to track a HANDWHEEL or as a slave to a
master with resolver feedback. It is “0” otherwise.
C.2.63. MAX_PHASE
Refer to the BASE_SPEED axis parameter for a description of this parameter.
C.2.64. MAXCAMACCEL
This axis parameter is used only in the context of File Driven Camming, only when
SYNC mode 3 is used. This parameter is most useful when synching on the fly (switching
cam tables without deSYNCing in between). If this axis parameter is non-zero, it will
limit the acceleration of the slave axis to its value, which is in user units/sec/sec. To
deactivate this feature, set the parameter value to 0.