Siemens SINUMERIK 828D Function Manual page 160

B1: Continuous­path Mode, Exact Stop, LookAhead
3.3 Continuous-path mode
• The block does not contain traversing motion (zero block).
This occurs when:
- Synchronized actions are active.
Normally, the interpreter eliminates zero blocks. However, if synchronous actions are active, this zero
block is included and also executed. In so doing, an exact stop is initiated corresponding to the active
programming. This allows the synchronous action to also switch.
- Zero blocks are generated by program jumps.
Synchronized axes
If a number of paths need to be synchronized (e.g. contour, special axis), then every path must always have its
own rounding area.
There are no practical means of achieving this exactly. Therefore, on the basis of the specific meaning of the
contour (geometry axis), the following procedure is applied:
Rounding behavior with synchronized paths
Original path for:
Geometry axes
Smooth
Smooth
Angular
Angular
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Orientation/
synchronized axis
Smooth Defined path is traversed exactly
Angular Intermediate blocks, the geometry axes follow the
path exactly, all orientation/synchronized axis paths
are smoothed.
Smooth Intermediate block, the geometry axes perform
rounding, all orientation/synchronized axis paths are
smoothed.
Angular Intermediate block, the geometry axes perform
rounding, all orientation/synchronized axis paths are
smoothed.
Rounding path outcome:
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions