Galil DMC-3425 Electronic Cam Local Mode, EAp where p = A,B p is the selected master axis

For example, assume that a gantry is driven by two axes, A and B, one on each side. 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:

GA, CA	Specify the commanded position of A as master for B.
GR,1	Set gear ratio for B as 1:1
GM,1	Set gantry mode
PR 3000	Command A motion
BG A	Start motion on A axis

You may also perform profiled position corrections in the electronic gearing mode. Suppose, for example, that you need to advance the slave 10 counts. Simply command

IP ,10 Specify an incremental position movement of 10 on the B axis.

Under these conditions, this IP command is equivalent to:

PR,10	Specify position relative movement of 10 on the B axis
BGB	Begin motion on the B axis

Often the correction is quite large. Such requirements are common when synchronizing cutting knives or conveyor belts.

Example - Synchronize two conveyor belts with trapezoidal velocity correction.

Instruction	Interpretation
GA,A	Define A as the master axis for B.
GR,2	Set gear ratio 2:1 for B
PR,300	Specify correction distance
SP,5000	Specify correction speed
AC,100000	Specify correction acceleration
DC,100000	Specify correction deceleration
BGB	Start correction

Electronic Cam (Local Mode)

The electronic cam is a motion control mode that enables the periodic synchronization of several axes of motion. Similar to the gearing mode, the DMC-3425 uses only A and B main axes as the master or slave.

The electronic cam is a more general type of electronic gearing which allows a table-based relationship between the axes. It allows synchronizing all the controller axes.

To illustrate the procedure of setting the cam mode, consider the cam relationship for the slave axis B, when the master is A. Such a graphic relationship is shown in Figure 6.4.

Step 1. Selecting the master axis

The first step in the electronic cam mode is to select the master axis. This is done with the instruction

EAp where p = A,B

p is the selected master axis

For the given example, since the master is a, we specify EAA

Step 2. Specify the master cycle and the change in the slave axis (es).

DMC-3425 Chapter 6 Programming Motion• 83