7. POSITIONING CONTROL
7
−
2
7.1.2
Positioning speed under interpolation control
The positioning speed of the servo system CPU determines the travel speed of the
controlled system.
(1) 1-axis linear control
Under 1-axis control, the travel speed is the positioning speed of the designated
axis.
(2) Linear interpolation control
Under linear interpolation control, the controlled system is controlled at the set
speed.
The positioning speed can be set for 2 to 4-axis control using one of the
following three methods:
•
combined speed designation
•
long-axis speed designation
•
reference-axis speed designation
Details of the servo system CPU control for each of these three methods are
described below.
(a) Resultant speed designation
The servo system CPU uses the travel value of each axis (D
1
to D
4
) to
calculate the positioning speed of each axis (V
1
to V
4
) from the set
positioning speed (V) of the controlled system.
The positioning speed of the controlled system is called the combined
speed.
Set the combined speed and the travel value of each axis in the servo
program.
2-axes linear interpolation control
0
V
1
V
V
2
0
(10000,15000)
Axis 2
Axis 1
Axis 1 travel value:
D
1
= 10,000 (PULSE)
Axis 2 travel value:
D
2
= 15,000 (PULSE)
Combined speed:
V = 7,000 (PLS/s)
The servo system CPU calculates
the positioning speed of each axis
from the above conditions, using the
following calculation formulas:
[Program Example]
ABS-2
Axis 1, 10000
Axis 2, 15000
Combined speed 7000
<K 50>
(PLS)
(PLS)
(PLS/s)
Axis 1 positioning speed: V
1
= V
×
D
1
/ D
1
2
+
D
2
2
Axis 2 positioning speed: V
2
= V
×
D
2
/ D
1
2
+
D
2
2
Example
