Settable Path Reference (Spath, Upath) - Siemens SINUMERIK 840D sl Programming Manual

Special motion commands

4.6 Settable path reference (SPATH, UPATH)

4.6 Settable path reference (SPATH, UPATH)
4.6
Function
During polynomial interpolation, the user may require two different relationships between the
velocity determining FGROUP axes and the other path axes: The latter should either be
controlled, synchronized to the path of the FGROUP axes or synchronized to the curve
parameters.
Therefore, for the axes not contained in FGROUP, there are two ways to follow the path:
● In synchronism to path S (SPATH)
● In synchronism to curve parameter U of the FGROUP axes (UPATH)
Both types of path interpolation are used in different applications and can be changed over
via G codes SPATH and UPATH.
Syntax
SPATH
UPATH
Significance
SPATH
UPATH
FGROUP
SPATH, UPATH
One of the two G codes (SPATH,UPATH) can be used to select and program the required
behavior.
The commands are modal. If SPATH is active, the axes are traversed synchronized with the
path; if UPATH is active, traversal is synchronized with the curve parameter.
UPATH and SPATH also define the interrelationship of the F word polynomial (FPOLY, FCUB,
FLIN) with path motion.
FGROUP activation
The path reference for the axes that are not contained in FGROUP, is set via the two
language commands SPATH and UPATH contained in the 45th G code group.
288
or
Path reference for FGROUP axes is arc length
Path reference for FGROUP axes is curve parameter
Definition of axes with path feed
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
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