Omron SYSMAC CJ Series, Operation Manual

Page: 17 / 371

Motion control concepts Section 1-3
5
1-3-1-1 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
Defining moves
Parameter Description
UNITS Unit conversion factor
ACCEL Acceleration rate of an axis in units/s
2
DECEL Deceleration rate of an axis in units/s
2
SPEED Demand speed of an axis in units/s
0
50
50
100
A
B
MOVEABS(100) AXIS(0)
MOVEABS(50) AXIS(1)
0
10
1 2 3 4 5 6
A
B
ACCEL=10
DECEL=10
SPEED=10
MOVE(40)