Siemens SINUMERIK 840D sl Programming Manual page 271

4.2 Spline interpolation (ASPLINE, BSPLINE, CSPLINE, BAUTO, BNAT, BTAN, EAUTO, ENAT, ETAN, PW, SD, PL)
Properties and use of the various spline types
Spline type
A spline
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
Properties and use
Properties:
The passes precisely through the specified intermediate points along the
•
curve.
The curve characteristic is tangential, but does not have continuous
•
curvature.
Produces hardly any undesirable oscillations.
•
The area of influence of changes to intermediate points along the curve is
•
local. This means that a change to an intermediate point along the curve only
affects up to max. 6 adjacent intermediate points.
Application:
The A spline is especially suitable for interpolating curves with large changes in
the gradient (e.g. staircase-type curves and characteristics).
Special motion commands
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