Siemens Sinumerik 840D sl Programming Manual page 248

Special Motion Commands
4.2 Spline interpolation (ASPLINE, BSPLINE, CSPLINE, BAUTO, BNAT, BTAN, EAUTO, ENAT, ETAN, PW, SD,
Distance between nodes (only B spline):
PL
<value>
Transitional behavior at the start of the spline curve (only A or C spline):
BAUTO
BNAT
BTAN
Transitional behavior at the end of the spline curve (only A or C spline):
EAUTO
ENAT
ETAN
Note
The programmable transitional behavior has no influence on the B spline. The B spline is
always tangential to the check polygon at its start and end points.
Supplementary conditions
• Tool radius compensation may be used.
• Collision monitoring is carried out in the projection in the plane.
248
The distances between nodes are suitably calculated internally.
The control can also machine pre-defined node clearances that
are specified in the so-called parameter-interval-length using the
PL command.
Parameter interval length
Range of values: As for path dimension
No specifications for the transitional behavior. The start is
determined by the position of the first point.
Zero curvature
Tangential transition to the previous block (delete position)
No specifications for the transitional behavior. The end is
determined by the position of the last point.
Zero curvature
Tangential transition to the previous block (delete position)
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
Job planning