Siemens SINUMERIK 840D Function Manual page 421

Figure 14-1
Multiple couplings
Up to 2 leading axes can be assigned to one coupled motion axis. The traversing movement of
the coupled motion axis then results from the sum of the traversing movements of the leading
axes.
Dependent coupled motion axis
A coupled motion axis is a "dependent coupled motion axis" when it traverses as a result of a
leading axis movement.
Independent coupled motion axis
A coupled motion axis is an "independent coupled motion axis" when it traverses as a result of
a direct traverse instruction. The traversing movement resulting from the coupled motion axis
is then the sum total of the traversing movements as a "dependent" and an "independent"
coupled motion axis.
Coupled motion axis as leading axis
A coupled motion axis can at the same time be the leading axis of a further coupled axis
grouping.
Coordinate system
Coupled axis motion is always executed in the base coordinate system (BCS).
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
Application example: Two-sided machining
M3: Coupled axes
14.1 Coupled motion
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