Siemens SINUMERIK 840DE Programming Manual page 195

2:
Input the maximum possible frequencies of each axis in the rounding area using MD 32440:
LOOKAH_FREQUENCY. The rounding area is defined such that no frequencies in excess of
the specified maximum can occur while the rounding motion is in progress.
3:
When rounding with G644, neither the tolerance nor the rounding distance are monitored.
Each axis traverses around a corner with the maximum possible dynamic response.
With SOFT, both the maximum acceleration and the maximum jerk of each axis is
maintained.
With the BRISK command, the jerk is not limited; instead, each axis travels at the maximum
possible acceleration.
References:/FB1/, B1, "Continuous Path Mode, Exact Stop and Look Ahead"
No rounding block/no rounding movement
Command outputs
Auxiliary functions, which are enabled after the end of the movement or before the next
movement interrupt continuous-path mode.
Positioning axes
Positioning axes always traverse according to the exact stop principle, positioning window
fine (as for G601). If an NC block has to wait for positioning axes, continuous-path mode is
interrupted on the path axes.
No corner rounding is performed in the following three situations:
1. Movement is stopped between the two blocks. This occurs when ...
2. The rounding block would slow down parts program processing. This occurs when ...
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
– The following block contains an auxiliary function output before the movement.
– The following block does not contain a path movement.
– An axis is traversed for the first time as a path axis for the following block when it was
previously a positioning axis.
– An axis is traversed for the first time as a positioning axis for the following block when
it was previously a path axis.
– Prior to thread cutting: The following block has G33 as a preparatory function and the
previous block does not.
– A changeover between BRISK and SOFT occurs.
– Axes involved in the transformation are not completely assigned to the path motion
(e.g., for oscillation, positioning axes).
– A rounding block is inserted between very short blocks. Since each block requires at
least one interpolation cycle, the added intermediate block would double the
machining time.
– A block transition G64 (continuous-path mode without rounding) can be traversed
without speed reduction. Rounding would increase the machining time. This means
that the value of the permitted overload factor
(MD 32310: MAX_ACCEL_OVL_FACTOR) affects whether a block transition is
rounded or not. The overload factor is taken into account only in conjunction with
G641/G642. The overload factor is ignored in corner rounding with G643.
5.3 Continuous-path mode (G64, G641, G642, G643, G644)
Path Action
5-13