Galil DMC-2X00 - Manual (Page 104)

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. B is defined as the master.
A,C,D are geared to master at ratios of 5,-.5 and 10 respectively.
Instruction Interpretation
GA B,,B,B Specify master axes as B
GR 5,,-.5,10 Set gear ratios
PR ,10000 Specify B position
SP ,100000 Specify B speed
BGB Begin motion
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-2x30 controller, where the C-axis is the master and A and B are the geared
axes.
Instruction Interpretation
MO C Turn C off, for external master
GA C,C Specify C as the master axis for both A and B.
GR 1.132,-.045 Specify gear ratios
Now suppose the gear ratio of the A-axis is to change on-the-fly to 2. This can be achieved by
commanding:
GR 2 Specify gear ratio for A axis to be 2
Gantry Mode
In applications where both the master and the follower are controlled by the DMC-2x00 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, A and B, on both sides. This requires the
gantry mode for strong coupling between the motors. The A-axis is the master and the B-axis is the
follower. To synchronize B with the commanded position of A, use the instructions:
Instruction Interpretation
GA, CA Specify the commanded position of A as master for B.
GR,1 Set gear ratio for Y as 1:1
GM,1 Set gantry mode
PR 3000 Command A motion
BG A Start motion on A axis
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• Chapter 6 Programming Motion
DMC-2X00