Omron TJ2-MC64 - PROGRAMMING Programming Manual page 261

Examples and tips
Position mode examples
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:
• The tuning is more simple, only the rigidity (Fn001) and, if necessary, the
feedforward gain (Pn109) needs to be set.
• The position loop in the servo is faster (250µs) than in Trajexia and it is
turned together with the speed loop.
• There is no sample time delay between "Target position" and "Measured
position".
To do a finetune the different gain parameters can be changed individually.
BASE(0)
ATYPE=41 'MECHATROLINK Position mode
SERVO=1
DRIVE_CONTROL=2 'To monitor the Following Error in
'DRIVE_MONITOR
WDOG=1
DEFPOS(0)
loop:
MOVE(81920)
WAIT IDLE
WA(100)
DEFPOS(0)
GOTO loop
PROGRAMMING MANUAL
fig. 12
TJ1-MC__
SERVO = OFF
Profile generator
Position loop
Trajexia
+
Position Loop is
_
deactivated
(Gains are not
Demanded Following
used!) position error
Measured
position
TJ1-ML__ SERVO
SERVO = OFF
ML-II
Position
Position Loop
command
Speed Loop
Torque Loop
Speed
command
E M
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