Siemens SINUMERIK 840D sl Function Manual page 71

Programming of orientation
With the extension of the generic orientation transformation to 6 axes, all three degrees of
freedom of the orientation can be freely selected. They can be uniquely defined through the
position of a rectangular Cartesian coordinate system. One axis direction, that of the third
axis, (typically in the Z direction) defines the orientation.
Two degrees of freedom are required for the specification of this direction. The third degree of
freedom is defined via a rotation around this direction, e.g. through the specification of an
angle THETA or a direction vector for one of the two other axes of the coordinate system, see
Chapter "Rotation of the Orientation Vector".
The new addresses AN3, BN3, CN3 define the direction of the second axis, of the coordinate
system (typically the Y axis) of the orientation normal vector. The programmed orientation
normal vector should be perpendicular to the orientation and is only possible when both
programmed vectors are not parallel or anti-parallel. Otherwise, alarm 4342 is output.
The direction of the first axis, the X axis, is then uniquely defined.
Default setting of the orientation normal vector
The default setting of the orientation normal vector in the transformation can also be defined
as for the default setting of the orientation in one of three ways:
Specification for the activation of the transformation
1. Vector components are transferred as parameters 8 to 10:
Parameter 1: Transformation No.
Parameter 2 - 4: Orientation vector,
Parameter 5 - 7: Rotary axis offsets
2. If no orientation normal vector has been specified and a tool is active, the vector is taken
from the tool data.
3. If no orientation normal vector has been specified and also no tool is active, the vector
defined in the following machine data is used.
MD24567 $MC_TRAFO6_BASE_ORIENT_NORMAL_1[0..2] (tool normal vector)
The position of the orientation coordinate system of a standard tool depends on the active
plane G17, G18, G19 according to the following table:
Table 1-5
Direction of the orientation vector
Direction of the orientation normal vector
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
Position of the orientation coordinate system
F2: Multi-axis transformations
1.7 Generic 5-axis transformation and variants
G17 G18
Z Y
Y X
G19
X
Z
71