Siemens sinumerik 840D sl Function Manual page 448

2.2.2 Activation of follow-up control
Programming
The programming is carried out using the pre-defined sub-program TANGON. When the
tangential control is activated, the name of the following axis which must be made to follow is
transferred to the control. This specification refers to the assignment between master and
following axes made beforehand with TANG. Refer to Section "Assignment between leading
axes and following axis". An angle between the tangent and the position of the following axis
can be specified optionally when follow-up is activated. This angle is maintained by the
control for as long as the following axis is made to follow. The angle is added to the angle
stored in the following machine data:
MD37402 $MA_TANG_OFFSET (preselection angle for tangential follow-up)
If the angle is zero both in TANGON and in the MD, the following axis takes the direction of
the tangent.
Figure 2-2
Activation is programmed as follows for the above example and an offset angle of 90
degrees:
TANGON(C, 90)
In response to every motion in path axes X and Y, following axis C is rotated to an angle of
90 degrees in the relation to the path tangent.
Special functions: Tangential Control (T3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Tangential control, offset angle of 90 degrees to path tangent
Detailed description
2.2 Using tangential follow-up control
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