Galil DMC-1700 Manual De Usuario

Descargar
Página de 253
96 • Chapter 6  Programming Motion 
DMC-1700/1800 
Additional Commands 
The commands VS n, VA n, and VD n are used to specify the vector speed, acceleration and deceleration.  The 
DMC-1700/1800 computes the vector speed based on the axes specified in the LM mode.  For example, LM XYZ 
designates linear interpolation for the X,Y and Z axes.  The vector speed for this example would be computed using 
the equation:  
VS
2
=XS
2
+YS
2
+ZS
2
, where XS, YS and ZS are the speed of the X,Y and Z axes.   
The controller always uses the axis specifications from LM, not LI, to compute the speed. 
VT is used to set the S-curve smoothing constant for coordinated moves.  The command AV n is the ‘After Vector’ 
trippoint, which halts program execution until the vector distance of n has been reached.  
An Example of Linear Interpolation Motion: 
#LMOVE label 
DP 0,0 
Define position of X and Y axes to be 0 
LMXY Define 
linear 
mode 
between X and Y axes. 
LI 5000,0 
Specify first linear segment 
LI 0,5000 
Specify second linear segment 
LE 
End linear segments 
VS 4000 
Specify vector speed 
BGS 
Begin motion sequence 
AV 4000 
Set trippoint to wait until vector distance of 4000 is reached 
VS 1000 
Change vector speed 
AV 5000 
Set trippoint to wait until vector distance of 5000 is reached 
VS 4000 
Change vector speed 
EN Program 
end 
In this example, the XY system is required to perform a 90
° turn.  In order to slow the speed around the corner, we 
use the AV 4000 trippoint, which slows the speed to 1000 count/s.  Once the motors reach the corner, the speed is 
increased back to 4000 cts / s. 
Specifying Vector Speed for Each Segment  
The instruction VS has an immediate effect and, therefore, must be given at the required time.  In some applications, 
such as CNC, it is necessary to attach various speeds to different motion segments.  This can be done by two 
functions:  < n  and  > m 
For example: 
LI x,y,z,w < n >m 
The first command, < n, is equivalent to commanding VSn at the start of the given segment and will 
cause an acceleration toward the new commanded speeds, subjects to the other constraints. 
The second function, > m, requires the vector speed to reach the value m at the end of the segment.  
Note that the function > m may start the deceleration within the given segment or during previous 
segments, as needed to meet the final speed requirement, under the given values of VA and VD. 
Note, however, that the controller works with one > m command at a time.  As a consequence, one 
function may be masked by another.  For example, if the function >100000 is followed by >5000, and 
the distance for deceleration is not sufficient, the second condition will not be met.  The controller will 
attempt to lower the speed to 5000, but will reach that at a different point. 
As an example, consider the following program. 
#ALT  
Label for alternative program 
DP 0,0  
Define Position of X and Y axis to be 0 
LMXY  
Define linear mode between X and Y axes.