Siemens SINUMERIK 840DE sl Function Manual page 260

K12 transformation definitions with kinematic chains
4.1 Function description
Tool orientation
The tool orientation can be specified as vector. The system variables $NT_BASE_ORIENT or
$NT_BASE_ORIENT_NORMAL are available for this. The orientations come into effect if no
tool is selected. If the vectors are not explicitly defined, the default setting is (0, 0, 1).
● $NT_BASE_ORIENT[n, 0 ...2]; defines the basic tool orientation via a vector, as shown in
the following example:
– $NT_BASE_ORIENT[1, 0] = 1.0; component in X-direction
– $NT_BASE_ORIENT[1, 1] = 1.5; component in Y-direction
– $NT_BASE_ORIENT[1, 2] = 100; component in Z-direction
● $NT_BASE_ORIENT_NORMAL[n, 0 ...2] defines a vector which stands vertically on the
basic tool orientation for orientation transformations with three degrees of freedom. If the
vectors are not explicitly defined, the default setting is (0, 1, 0).
● $NT_IGNORE_TOOL_ORIENT[n]; if the system variable is set, the values from the system
variables $NT_BASE_ORIENT and $NT_BASE_ORIENT_NORMAL are also used when a
tool is active.
Treatment of singular points (poles)
If poles (Page 157) are encountered over the course of processing, the behavior at the pole can
be set via two system variables:
● $NT_POLE_LIMIT; defines the end angle tolerance, i.e. the angle by which the polar axis
can deviate from the programmed value for the 5-axis transformation.
● $NT_POLE_TOL; defines the end angle tolerance for interpolation through the pole.
Real-time velocity monitoring
The machine data $MC_TRAFO_ORI_ONLINE_CHECK_LIM and
$MC_TRAFO_ORI_ONLINE_CHECK_LIMR define the linear or rotary position difference
between the pre-run and main run as of which the real-time velocity monitoring and limiting is
activated. The position differences are formed from the positions of the linear and rotary axes.
Use of CYCLE832 (High Speed Settings)
When Cycle832 with transformations is used, the rotary axes are determined in the following
way:
● The rotary axes that are contained in the first transformation with a kinematic chain of the
type TRAOR_DYN are entered.
● If there is no transformation with a kinematic chain, the rotary axes that are contained in the
last transformation defined via machine data are entered.
The reference radius for both rotary axes is then set via FGREF.
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Function Manual, 06/2019, A5E47435470B AA
Transformations