User manual

TMCM-1640 TMCL Firmware V2.00 Manual (Rev. 2.00 / 2012-JUL-31) 53
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NOTE:
- In order to minimize the time until this flag becomes set, the positioning tolerance MVP target reached
distance can be chosen with axis parameter 10.
- Since the motor typically is assumed not to signal target reached when the target was just passed in a
short moment at a high velocity, additionally the maximum target reached velocity (MVP target reached
velocity) can be defined by axis parameter 7.
- A value of zero for axis parameter 7 is the most universal, since it implies that the motor stands still at the
target. But when a fast rising of the position end flag is desired, a higher value for the MVP target reached
velocity parameter will save a lot of time. The best value should be tried out in the actual application.
CORRELATION OF AXIS PARAMETERS 10 AND 7, THE TARGET POSITION, AND THE POSITION END FLAG
|Velocity|
Position
Target position
(set via MVP)
Max. positioning
velocity
MVP target reached distance
Slow-down-distance
Motor regulated by
Velocity PID
Motor regulated by
combination of
Velocity and Position
PID
Acceleration
MVP target
reached velocity
Target reached flag
only set when velocity
and position are in
this area.
Figure 7.5: Positioning algorithm
Depending on motor and mechanics a low oscillation is normal. This can be reduced to at least +/-1 encoder
steps. Without oscillation the regulation cannot keep the position!