Omron GRT1-ML2 Hardware Reference Manual page 15

System philosophy
Relative and absolute moves
To move a single axis either the command MOVE for a relative move or the
command MOVEABS for an absolute move is used. Each axis has its own
move characteristics, which are defined by the axis parameters.
Suppose a control program is executed to move from the origin to an axis
no. 0 (A) coordinate of 100 and axis no. 1 (B) coordinate of 50. If the speed
parameter is set to be the same for both axes and the acceleration and
deceleration rate are set sufficiently high, the movements for axis 0 and axis
1 will be as shown in the figure.
At start, both the axis 0 and axis 1 moves to a coordinate of 50 over the
same duration of time. At this point, axis 1 stops and axis 0 continues to
move to a coordinate of 100.
The move of a certain axis is determined by the axis parameters. Some
relevant parameters are:
/i
Parameter Description
UNITS Unit conversion factor
ACCEL Acceleration rate of an axis in units/s
DECEL Deceleration rate of an axis in units/s
SPEED Demand speed of an axis in units/s
Defining moves
The speed profile in this figure shows a simple MOVE operation. Axis A is
the time, axis B is the speed. The UNITS parameter for this axis has been
defined for example as meters. The required maximum speed has been set
to 10 m/s. In order to reach this speed in one second and also to decelerate
to zero speed again in one second, both the acceleration as the deceleration
2
rate have been set to 10 m/s . The total distance travelled is the sum of
distances travelled during the acceleration, constant speed and deceleration
segments. Suppose the distance moved by the MOVE command is 40 m,
the speed profile is given by the figure.
HARDWARE REFERENCE MANUAL
2
2
2
fig. 3
B
MOVEABS(100) AXIS(0)
MOVEABS(50) AXIS(1)
50
0
50
fig. 4
B
10
0 1 2 3 4 5
A
100
ACCEL=10
DECEL=10
SPEED=10
MOVE(40)
A
6
10