Smoothing Of Orientation Characteristic - Siemens SINUMERIK 840D sl Function Manual

F2: Multi-axis transformations
1.9 Orientation
General structure of an NC block that be compressed
The general structure of an NC block that can be compressed can therefore look like this:
N... X=<...> Y=<...> Z=<...> A3=<...> B3=<...> C3=<...> THETA=<...> F=<...>
or
N... X=<...> Y=<...> Z=<...> A2=<...> B2=<...> C2=<...> THETA=<...> F=<...>
Programming tool orientation using rotary axis positions
Tool orientation can be also specified using rotary axis positions, e.g. with the following
structure:
N... X=<...> Y=<...> Z=<...> A=<...> B=<...> C=<...> THETA=<...> F=<...>
In this case, compression is executed in two different ways, depending on whether large
radius circular interpolation is executed. If no large radius circular interpolation takes place,
then the compressed change in orientation is represented in the usual way by axial
polynomials for the rotary axes.
Activation/deactivation
Compressor functions are activated using the modal G codes COMPON, COMPCURV or
COMPCAD.
COMPOF terminates the compressor function.
Programming example
See " Example: Compression of an orientation [Page 137] "
References
The COMPON, COMPCURV and COMPCAD compression functions are described in:
Function Manual Basic Functions; Continuous Path Mode, Exact Stop, LookAhead (B1),
Chapter: "NC block compression"
1.9.4

Smoothing of orientation characteristic

Introduction
With many of the NC programs for 5-axis machining created with CAD/CAM systems it
happens that although the contour characteristic is sufficiently smooth in accordance with the
underlying geometry the orientation characteristic contains more or less large fluctuations.
These fluctuations in orientation result in very unsmooth running of the orientation axes with
permanent acceleration and braking. The compensating motions that the linear axes then
have to carry out require that the linear axes also have to be accelerated and braked
permanently. Due to these unnecessary accelerations, the possible path velocity is strongly
limited and consequently the machining time unnecessarily prolongated.
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Function Manual, 09/2011, 6FC5397-2BP40-2BA0
Special Functions