Galil DMC-2X00 user manual Simple Master/Slave, Electronic Gearing, Gantry Mode

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

DMC-2X00 Chapter 6 Programming Motion y 49