Polynomial Interpolation (Poly, Polypath, Po, Pl) - Siemens SINUMERIK 840D sl Programming Manual

4.5

Polynomial interpolation (POLY, POLYPATH, PO, PL)

4.5
Function
Polynomial interpolation (POLY) is not spline interpolation in the true sense. Its main
purpose is to act as an interface for programming externally generated spline curves where
the spline sections can be programmed directly.
This mode of interpolation relieves the NC of the task of calculating polynomial coefficients. It
can be applied optimally in cases where the coefficients are supplied directly by a CAD
system or postprocessor.
Syntax
3rd degree polynomial:
POLY PO[X]=(xe,a2,a3) PO[Y]=(ye,b2,b3) PO[Z]=(ze,c2,c3) PL=n
or extension to 5th degree polynomial and new polynomial syntax:
POLY X=PO(xe,a2,a3,a4,a5) Y=PO(ye,b2,b3,b4,b5) Z=PO(ze,c2,c3,c4,c5)
PL=n
POLYPATH("AXES","VECT")
Significance
POLY
POLYPATH
PO[axis identifier/variable]
X, Y, Z
xe, ye, ze
a2, a3, a4, a5
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
4.5 Polynomial interpolation (POLY, POLYPATH, PO, PL)
Activation of polynomial interpolation with a
block containing POLY.
Polynomial interpolation can be selected for
the both AXIS or VECT axis groups
End points and polynomial coefficients
Axis identifier
Specification of end position for the particular
axis; value range as for path dimension
The coefficients a
with their value; value range as for path
dimension. The last coefficient in each case
can be omitted if it equals zero.
Special motion commands
, a , a , and a are written
2 3 4 5
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