Siemens SINUMERIK 828D Programming Manual page 119

Path reference factors for orientation axes with FGREF
With orientation axes the mode of operation of the
whether the change in the orientation of the tool is implemented by means of rotary axis or
vector interpolation.
In the case of rotary axis interpolation, as is the case with rotary axes, the relevant
factors of the orientation axes are calculated individually as reference radius for the axis
paths.
In the case of vector interpolation, an effective
geometric mean value of the individual
FGREF[effective] = nth root of [(FGREF[A] * FGREF[B]...)]
where:
Example:
Since there are two orientation axes for a standard 5-axis transformation, the effective factor
is, therefore, the root of the product of the two axial factors:
FGREF[effective] = square root of [(FGREF[A] * FGREF[B])]
Note
It is, therefore, possible to use the effective factor for orientation axes
reference point on the tool to which the programmed path feedrate refers.
Fundamentals
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
A: Axis identifier of 1st orientation axis
B: Axis identifier of 2nd orientation axis
C: Axis identifier of 3rd orientation axis
n: Number of orientation axes
7.1 Feedrate (G93, G94, G95, F, FGROUP, FL, FGREF)
FGREF[]
factor, which is calculated as the
FGREF
factors, is applied.
FGREF
Feed control
factors is dependent upon
to define a
FGREF
FGREF
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