Siemens SINUMERIK 840D sl Function Manual page 775

of the plane then specifies the axis, around which the other axis of the plane must be rotated
in order to move this into the line of intersection, which the rotated plane forms with the plane
surrounded by the other and the third axis. This definition ensures that, in the case that one
of the two programmed angles is towards zero, the defined plane enters the plane, which is
created if only one axis is programmed (e.g. with ROT or AROT).
The diagram shows an example where X and Y are programmed. Y specifies the angle here,
through which the X axis must rotate around the Y axis to bring the X axis to the line of
intersection formed by the inclined plane and the X-Z plane. The same principle applies for
the programmed value of X.
Note
In the shown position of the inclined plane the value of Y is positive, that of X on the other hand
negative.
The specification of the solid angle does not define the orientation of the two-dimensional
coordinate system within the plane (i.e. the angle of rotation around the surface normal vector).
The position of the coordinate system is thus determined so that the rotated first axis lies in
the plane which is formed by the first and third axes of the non-rotated coordinate system.
This means that
● When programming X and Y the new X axis lies in the old Z-X plane.
● When programming Z and X the new Z axis lies in the old Y-Z plane.
● When programming Y and Z the new Y axis lies in the old X-Y plane.
If the required coordinate system does not correspond to this basic setting, then an additional
rotation must be performed with AROT....
The programmed solid angles are converted to the equivalent Euler angles according to the
zy'x" convention (RPY angle) or zx'z" convention when entering depending on the machine
data:
MD10600 $MN_FRAME_ANGLE_INPUT_MODE.
These then appear in the display.
Frame rotation in tool direction
With the language command TOFRAME, which also existed in older software versions, it is
possible to define a frame whose Z axis points in the tool direction.
An already programmed frame is then overwritten by a frame which describes a pure rotation.
Any work offsets, mirrorings or scalings existing in the previously active frame are deleted.
This response is sometimes interfering. It is often particularly practical to retain a work offset,
with which the reference point in the workpiece is defined.
The language command TOROT is then also used. This command overwrites only the rotation
component in the programmed frame and leaves the remaining components unchanged. The
rotation defined with TOROT is the same as that defined with TOFRAME.
TOROT is, like TOFRAME, independent of the availability of an orientable toolholder. This
language command is also especially useful for 5-axis transformations.
The new language command TOROT ensures consistent programming with active orientable
toolholders for each kinematics type.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
K2: Axis Types, Coordinate Systems, Frames
10.5 Frames
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