Galil Motion Control DMC-42 0 Series, User Manual

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T
D
VS
T s
t a
  
0 407 .
The velocities along the X and Y axes are such that the direction of motion follows the specified path, yet the vector
velocity fits the vector speed and acceleration requirements.
For example, the velocities along the X and Y axes for the path shown in Figure A.8 are given in Figure A.10.
Figure A.10 shows the vector velocity. It also indicates the position point along the path starting at A and ending at
D. Between the points A and B, the motion is along the Y axis. Therefore,
Vy = Vs
and
Vx = 0
Between the points B and C, the velocities vary gradually and finally, between the points C and D, the motion is in
the X direction.
Figure A.10: Vector Axes Velocities
Electronic Gearing
This mode allows up to 8 axes to be electronically geared to some master axes. The masters may rotate in both
directions and the geared axes will follow at the specified gear ratio. The gear ratio may be different for each axis
and changed during motion.
The command GAX yzw or GA ABCDEFGH specifies the master axes. GR x,y,z,w specifies the gear ratios for the
slaves where the ratio may be a number between ±127.9999 with a fractional resolution of .0001. There are two
modes: standard gearing and gantry mode. The gantry mode (enabled with the command GM) allows the gearing
to stay enabled even if a limit is hit or an ST command is issued. GR 0,0,0,0 turns off gearing in both modes.
The command GM x,y,z,w select the axes to be controlled under the gantry mode. The parameter 1 enables gantry
mode, and 0 disables it.
GR causes the specified axes to be geared to the actual position of the master. The master axis is commanded with
motion commands such as PR, PA or JG.
When the master axis is driven by the controller in the jog mode or an independent motion mode, it is possible to
define the master as the command position of that axis, rather than the actual position. The designation of the
commanded position master is by the letter, C. For example, GACX indicates that the gearing is the commanded
position of X.
An alternative gearing method is to synchronize the slave motor to the commanded vector motion of several axes
performed by GAS. For example, if the X and Y motor form a circular motion, the Z axis may move in proportion to
the vector move. Similarly, if X,Y and Z perform a linear interpolation move, W can be geared to the vector move.
Chapter 6 Programming Motion ▫ 73 DMC-42x0 User Manual
A
B
D
(a)
(b)
(c)
time
C