Siemens sinumerik 840D sl Function Manual page 696

Figure 2-30 Orientation angle for 5-axis kinematic
It is possible to define orientation axes for the handling transformation package.
Note
Additional information can be found in:
/FB3/ Function Manual, Special Functions, "Orientation Axes"
and
/PGA/ Programming Guide Advanced, "Orientation Axes".
2.6 Singular positions and how they are handled
The calculation of the machine axes to a preset position, i.e. position with orientation, is not
always clear. Depending on the machine kinematic, there may be positions with an infinite
number of solutions. These positions are called "singular".
Special functions: Handling Transformation Package (TE4)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
2.6 Singular positions and how they are handled
Detailed description
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