Siemens Sinumerik 840D sl Programming Manual page 253

4.2 Spline interpolation (ASPLINE, BSPLINE, CSPLINE, BAUTO, BNAT, BTAN, EAUTO, ENAT, ETAN, PW, SD,
Spline type
B spline
Job planning
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
Properties and use
Features:
• Does not run through the specified intermediate points along the curve, but
only close to them. The intermediate points to not attract the curve. The curve
characteristic can be additionally influenced by weighting the intermediate
points using a factor.
• The curve characteristic is tangential with continuous curvature.
• Does not generate 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:
Their B spline is primarily intended as interface to CAD systems.
Special Motion Commands
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