Siemens sinumerik 840D sl Function Manual page 35

MD21108 $MC_POLE_ORI_MODE
The following machine data can be used to set the response for large circle interpolation in
pole position as follows:
MD21108 $MC_POLE_ORI_MODE (behavior during large circle interpolation at pole
position)
Does not define the treatment of changes in orientation during large circle interpolation
unless the starting orientation is equal to the pole orientation or approximates to it and the
end orientation of the block is outside the tolerance circle defined in the following machine
data.
TRAFO5_NON_POLE_LIMIT1/2
The position of the polar axis is arbitrary in the polar position. For the large circle
interpolation, however, a specified orientation is required for this axis.
The following machine data is coded decimally.
MD21108 $MC_POLE_ORI_MODE
The units define the behavior if start orientation coincides with pole position and the decade
the behavior if start orientation is within the tolerances defined by the following machine
data:
$ MC_TRAFO5_NON_POLE_LIMIT1/2
All setting values are described in "Channel-specific Machine Data".
2.2 3-axis and 4-axis transformations
Introduction
3-axis and 4-axis transformations are special types of the 5-axis transformation initially
described. Orientation of the tool is possible only in the plane perpendicular to the rotary
axis. The transformation supports machine types with movable tool and movable workpiece.
Kinematics variants
The variants specified in the following table apply both for 3-axis and 4-axis transformations.
Variants of 3-axis and 4-axis transformations
Machine type swiveling/
1
Special functions: 3-Axis to 5-Axis Transformation (F2)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
rotary axis is
rotary parallel
Tool X
Y
Z
Z
any
2.2 3-axis and 4-axis transformations
orientation MD:
plane $MC_TRAFO_T
YPE_n
Y - Z 16
X - Z 18
X - Y 20
X - Y 21
any * 24
Detailed description
Tool orientation in
zero position
Z
Y
X
any
29