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Virtual axis, Ecam master example, Sinusoidal motion example – Galil DMC-2X00 User Manual

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SHA Servo

Here

WT1000

Wait 1 sec (1000 msec)

CMA

Specify contour mode on A axis

DT2

Set contour data rate to be 2

2

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.

DMC-2X00

Chapter 6 Programming Motion

y 105