Using the ramped gearing, the slave will engage gearing gradually. Since the gearing is engaged over the interval
of 6000 counts of the master, the slave will only travel ~3396 counts and ~135 counts respectively. The difference
between these two values is stored in the _GPn operand. If exact position synchronization is required, the IP
command is used to adjust for the difference.
Command Summary - Electronic Gearing
COMMAND DESCRIPTION
GA n
Specifies master axes for gearing where:
n = X,Y,Z or W or A,B,C,D,E,F,G,H for main encoder as master
n = CX,CY,CZ, CW or CA, CB,CC,CD,CE,CF,CG,CH for commanded position.
n = DX,DY,DZ or DW or DA, DB, DC, DD, DE, DF,DG,DH for auxiliary encoders
n = S or T for gearing to coordinated motion.
GD a,b,c,d,e,f,g,h
Sets the distance the master will travel for the gearing change to take full effect.
_GPn
This operand keeps track of the difference between the theoretical distance traveled if
gearing changes took effect immediately, and the distance traveled since gearing
changes take effect over a specified interval.
GR a,b,c,d,e,f,g,h
Sets gear ratio for slave axes. 0 disables electronic gearing for specified axis.
GM a,b,c,d,e,f,g,h
X = 1 sets gantry mode, 0 disables gantry mode
MR x,y,z,w
Trippoint for reverse motion past specified value. Only one field may be used.
MF x,y,z,w
Trippoint for forward motion past specified value. Only one field may be used.
Example - Simple Master Slave
Master axis moves 10000 counts at slew speed of 100000 counts/sec. Y is defined as the master. X,Z,W are geared
to master at ratios of 5,-.5 and 10 respectively.
GA Y,,Y,Y
Specify master axes as Y
GR 5,,-.5,10
Set gear ratios
PR ,10000
Specify Y position
SP ,100000
Specify Y speed
BGY
Begin motion
Example - Electronic Gearing
Objective: Run two geared motors at speeds of 1.132 and -0.045 times the speed of an external master. The
master is driven at speeds between 0 and 1800 RPM (2000 counts/rev encoder).
Solution: Use a DMC-4133 controller, where the Z-axis is the master and X and Y are the geared axes.
MO Z
Turn Z off, for external master
GA Z, Z
Specify Z as the master axis for both X and Y.
GR 1.132,-.045
Specify gear ratios
Now suppose the gear ratio of the X-axis is to change on-the-fly to 2. This can be achieved by commanding:
GR 2
Specify gear ratio for X axis to be 2
Example - Gantry Mode
In applications where both the master and the follower are controlled by the DMC-41x3 controller, it may be
desired to synchronize the follower with the commanded position of the master, rather than the actual position.
This eliminates the coupling between the axes which may lead to oscillations.
For example, assume that a gantry is driven by two axes, X,Y, on both sides. This requires the gantry mode for
strong coupling between the motors. The X-axis is the master and the Y-axis is the follower. To synchronize Y
with the commanded position of X, use the instructions:
Chapter 6 Programming Motion ▫ 76 DMC-41x3 User Manual
To Next Page
Loading...
