Examples and tips
PROGRAMMING MANUAL
235
Revi
si
on 3.0
Example 8
fig. 11
Opposite to the P_GAIN, where the higher, the better (the limit is
when the mechanical system starts vibrating), for the VFF_GAIN
there is an optimum value (the one in test 6), values higher than
this value has an error proportional to the speed/acceleration but
with different sign. The required correction is too large.
The parameter values for the example are:
/i
Position mode examples
fig. 12
In this mode the position and speed loop are closed in the Servo
Driver. The TJ1-ML__ sends the position command through the
MECHATROLINK-II network to the Servo Driver, and reads the
position feedback.
Note that this system has no sample delay as compared to the
position loop in the Servo Driver, the Demand_Position in cycle "n"
with the Measured_Position in cycle "n".
The Trajexia, for the internal handling, continues to use its own
position loop, so the Following Error that read in the Axis parameter
in Trajexia is not the real one in the Servo-drive. To read the correct
Following Error use DRIVE_MONITOR.
Adjust the rigidity of the servo, the speed loop gain and the position
loop gain at the same time using just proportional position gain.
The results are similar to the MECHATROLINK-II Speed mode with
the advantages:
Motion Parameter values
P_Gain=131072
VFF_GAIN=1650000
Fn001=6
Profile generator
Following
Error
Demanded
Position
Trajexia Position
Loop is
desactivated.
(Gains are not
used!)
Measured
Position
Speed
Command
ML-II
Position
Command
Position
+
_
SERVO
SERVO
E
M
Position Loop
Speed Loop
Torque Loop
NOP
TJ1-MC16
TJ1-ML16 SERVO
I52E-EN-03.book Seite 235 Freitag, 29. Juni 2007 11:55 11
