Siemens SINUMERIK 840D sl Programming Manual page 611

possibilities are available for selecting the axes not contained in FGROUP on how they should
follow the FGROUP axes:
● Synchronous to path S (SPATH)
● Synchronous to curve parameter U (UPATH)
Syntax
SPATH
UPATH
Meaning
SPATH:
UPATH:
Note
UPATH and SPATH also define the interrelationship of the F word polynomial (FPOLY, FCUB,
FLIN) with path motion.
Boundary conditions
SPATH and UPATH have no meaning for:
● Linear interpolation (G1)
● Circular interpolation (G2, G3)
● Thread blocks (G33, G34, G35, G33x, G63)
● All path axes are contained in FGROUP
Example
The following example shows the difference between both types of motion control.
Program code
N10 FGROUP(X,Y,Z)
N15 G1 X0 A0 F1000 SPATH
N20 POLY PO[X]=(10,10) A10
Program code
N10 FGROUP(X,Y,Z)
N15 G1 X0 A0 F1000 UPATH
N20 POLY PO[X]=(10,10) A10
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
The axes not contained in FGROUP are traversed with reference to path S
The axes not contained in FGROUP are traversed with reference to curve parameter U
3.7 Special motion commands
; SPATH
; UPATH
Work preparation
611