Siemens SINUMERIK 840DE sl Function Manual page 259

3 and 4-axis transformation
3 and 4-axis transformations are special cases of the 5-axis transformation, see 3-axis and 4-
axis transformations (Page 160). Possible versions are listed below:
Transformation
3-axis transformation
4-axis transformation
Defining machine kinematics
The corresponding machine kinematics must be defined via a kinematic chain.
Linear axes (geometry axes)
The movements of the rotary axes are compensated via compensating movements of up to
three linear axes. The linear axes are defined via the kinematic chain as an element of the type
"AXIS_LIN". For the transformation, they are referenced with $NT_GEO_AX_NAME. The
geometry axes do not have to be vertical on top of one another and their position relative to one
another can be changed by means of rotary axes. However, the limitation that they cannot be
linearly dependent on one another applies.
The position of linear axes that are not defined as geometry axes is not changed by the
transformation.
Rotary and orientation axes
The rotary axes are defined via the kinematic chain as an element of the type "AXIS_ROT". For
the transformation, they are referenced with $NT_ROT_AX_NAME and are thus designated as
orientation axis. The position of these axes is assumed to be changeable to achieve a specific
orientation.
An offset from zero can be defined using system variable $NT_ROT_AX_OFFSET for the rotary
axes (1, 2, or 3) of the orientation transformation.
All of the other rotary axes are redundant rotary axes and are included in the calculation with
their current position values (constant rotations). Redundant machine axes (real rotary axes)
must be located in the kinematic chain in front of the first orientation axis. Additional redundant
rotary axes (manual rotary axes or rotating machine axes) can be inserted at any point.
The number of rotary axes is restricted to 6.
Transformations
Function Manual, 06/2019, A5E47435470B AA
Characteristics
2 translation axes (linear axes)
1 rotary axis
3 translation axes (linear axes)
1 rotary axis
K12 transformation definitions with kinematic chains
4.1 Function description
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