Siemens SINUMERIK 840D sl Function Manual page 215

Parameterization
Adaptation factor of the dynamic path response
Via the adaptation factor of the dynamic path response, temporary changes in the path velocity
are executed with smaller dynamic response limit values.
The adaptation factor is to be set on a channel-specific basis:
● For traversing motions with acceleration without jerk limitation (BRISK) via:
MD20465 $MC_ADAPT_PATH_DYNAMIC[ 0 ]
→ The adaptation factor acts on the acceleration.
● For traversing motions with acceleration with jerk limitation (SOFT) via:
MD20465 $MC_ADAPT_PATH_DYNAMIC[ 1 ]
→ The adaptation factor acts on the jerk.
Axis-specific limit frequencies
The dynamic response limiting should only be active during deceleration and acceleration
processes that trigger mechanical vibrations larger than a specific limiting frequency, thus
causing excitation of machine resonances.
This limit frequency from which the dynamic response limiting activates, is specified on an axis-
specific basis via the machine data:
MD32440 $MA_LOOKAH_FREQUENCY (smoothing frequency for LookAhead)
For further information, see Section "Smoothing of the path velocity (Page 210)".
Mode of operation
During processing and via all the axes involved in the path, the controller cyclically establishes
the minimum of all the limit frequencies to be the limit frequency (f) for the adaptation of the
dynamic response and calculates the relevant time window (t
t
adapt
The size of the relevant time window t
1. The time needed to change the velocity is less than t
The acceleration rates are reduced by a factor > 1 and ≤ the value written in machine data:
MD20465 ADAPT_PATH_DYNAMIC (adaptation of the path dynamics)
The reduction in acceleration rate increases the time taken to change the velocity.
The following cases are different:
– The acceleration rate is reduced with a value less than MD20465 so that the process
– The acceleration time is reduced with the value written in MD20465. The process lasts
2. The time needed to change the velocity is greater than t
No dynamic response adaptation is required.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
= 1 / f
lasts for t [s]. The permitted reduction does not need to be fully utilized.
adapt
less than t despite the reduced acceleration. The permitted reduction was fully
adapt
utilized.
B1: Continuous-path mode, Exact stop, Look Ahead
determines the further behavior:
adapt
:
adapt
adapt
4.4 Dynamic adaptations
) from this:
adapt
:
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