Siemens SINUMERIK 808D Function Manual page 36

● : Continuous velocity and acceleration block transitions
COMPCURV
COMPCAD
The compressor function
blocks. The polynomial blocks have constant velocity and acceleration at the block transitions. Corners that are desirable are
identified as such and taken into account.
The maximum tolerable deviation of the calculated path to the programmed points can be specified using machine data for
all compressor functions. In contrast to
neighboring paths with
COMPCAD
the programmed points.
The common objective of compressor functions is to optimize the surface quality and machining speed by achieving
continuous block transitions and increasing the path length for each block.
is very CPU time and memory-intensive. It is recommended that
COMPCAD
improvements were not successful using measures in the CAD/CAM program.
General
● The position data in the blocks to be compressed can be realized as required, e.g.
● The compression operation is then interrupted by every other command, e.g. auxiliary function output, in and between
the blocks to be compressed.
Availability
NC block compression is only available for the milling versions of the control system.
Parameterization
The following machine and setting data must be set for the parameterization of the NC block compression:
Channel-specific machine data
Number Identifier $MC_
MD20170 COMPRESS_BLOCK_PATH_LIMIT
MD20172 COMPRESS_VELO_TOL
MD20482 COMPRESSOR_MODE
Channel-specific setting data
Number Identifier $SC_
SD42470 CRIT_SPLINE_ANGLE
SD42475 COMPRESS_CONTUR_TOL
Note
Corner limit angle and compressor function COMPCAD
The corner limit angle for
approximate measure for corner detection. By evaluating the plausibility, the compressor can also identify flatter block
transitions as corners and larger angles as outliers.
Axial machine data
Number Identifier $MA_
MD33100 COMPRESS_POS_TOL
Recommended settings for retroactive machine data
When using the compressor function, the following settings are recommended for the retroactive machine data on the
compressor function:
Number Identifier
MD18360 $MN_MM_EXT_PROG_BUFFER_SIZE
(FIFO buffer size for execution from external source)
36
can generate one polynomial block from theoretically any number of linear and circular
COMPCAD
and
COMPON
. In fact, attempts to achieve - under similar conditions - also similar deviations from
COMPCAD
set via the setting data SD42470 $SC_CRIT_SPLINE_ANGLE is only used as an
COMPCAD
, the specified tolerances are not used in different directions in
COMPCURV
COMPCAD
Meaning
Maximum traversing length of NC block for compression
Maximum permissible deviation from path feed for compression
Setting the mode of operation of the compressor
Meaning
Corner limit angle for
Maximum permissible contour deviation with compression
Meaning
Maximum permissible path deviation with compression
is only used there where surface
,
X100 X=AC(100)
COMPCAD
Recommended value
100
,
X=R1*(R2+R3)
Function Manual
01/2017