Galil DMC-2X00 user manual Virtual Axis, Ecam master example, Sinusoidal Motion Example

SHA	Servo Here
WT1000	Wait 1 sec (1000 msec)
CMA	Specify contour mode on A axis
DT2	Set contour data rate to be 22 msec
i=0	Set array index to 0
#LOOP3	Subroutine to execute contour points
CD dx[i];WC	Contour data command; Wait for next contour point
i=i+1	Update index
JP#LOOP3,i<500	Continue until all array elements have been executed
DT0	Set contour update rate to 0
CD0	Disable the contour mode (combination of DT0 and CD0)
EN	End program

For additional information about automatic array capture, see Chapter 7, Arrays.

Virtual Axis

The DMC-2x00 controller has an additional virtual axis designated as the N axis. This axis has no encoder and no DAC. However, it can be commanded by the commands:

AC, DC, JG, SP, PR, PA, BG, IT, GA, VM, VP, CR, ST, DP, RP, EA.

The main use of the virtual axis is to serve as a virtual master in ECAM modes, and to perform an unnecessary part of a vector mode. These applications are illustrated by the following examples.

Ecam master example

Suppose that the motion of the AB axes is constrained along a path that can be described by an electronic cam table. Further assume that the ecam master is not an external encoder but has to be a controlled variable.

This can be achieved by defining the N axis as the master with the command EAN and setting the modulo of the master with a command such as EMN= 4000. Next, the table is constructed. To move the constrained axes, simply command the N axis in the jog mode or with the PR and PA commands.

For example,

PAN = 2000

BGN

will cause the AB axes to move to the corresponding points on the motion cycle.

Sinusoidal Motion Example

The x axis must perform a sinusoidal motion of 10 cycles with an amplitude of 1000 counts and a frequency of 20 Hz.

This can be performed by commanding the A and N axes to perform circular motion. Note that the value of VS must be

VS = 2π * R * F

where R is the radius, (amplitude) and F is the frequency in Hz. Set VA and VD to maximum values for the fastest acceleration.

60 • Chapter 6 Programming Motion DMC-2X00