Siemens SINUMERIK 840D sl Function Manual page 179

Profile for limit velocity
The use of a velocity profile can be controlled during rounding using the hundreds digit in the
machine data:
MD20480 $MC_SMOOTHING_MODE (rounding behavior with G64x)
Hundred's place:
< 100:
≥100:
1xx:
2xx:
Note
See also:
MD28530 $MC_MM_PATH_VELO_SEGMENTS (number of memory elements for limiting
the path velocity)
2.3.4 Rounding with maximum possible dynamic response on each axis
How this type of rounding differs from existing types
Unlike existing rounding types, which are activated with G codes G641, G642 and G643, in
this case, the maximum possible dynamic response on each axis takes priority.
Activation
This type of rounding is activated by G code G644. Further information needs to be
programmed and/or entered in the machine data, depending on the setting.
Note
G644 is not available with an active kinematic transformation. The system switches internally
to G642.
Basic logic functions: Continuouspath Mode, Exact Stop, LookAhead (B1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
A profile of the limit velocity is calculated within the rounding area, based on the
defined maximum values for acceleration and jerk on the participating axes or
path.
This can lead to an increase in the path velocity in the rounding area and
therefore to the acceleration of the participating axes.
A profile of the limit velocity is not calculated for rounding blocks with
G641/G642. A constant velocity limit is specified instead.
This prevents the participating axes being accelerated into the rounding area
during rounding with G641/G642. However, in certain cases, this setting can
cause the rounding blocks to be traversed too slowly, especially in large
rounding areas.
No velocity profile for G641
No velocity profile for G642
Detailed description
2.3 Continuous -path mode
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