Path Action; General Notes; Programming Path Travel Behavior - Siemens SINUMERIK 840Di sl Programming Manual

Path Action

5.1

General notes

5.1.1

Programming path travel behavior

In this section you will find descriptions of commands, with which you can adapt the travel
behavior at the block boundaries optimally for special requirements. For instance, you can
position axes quickly enough or correspondingly reduce path contours over several blocks
taking into account an acceleration limit and the overload factor of the axes. Greater
inaccuracies of the path contour occur with increasing speed.
Path commands are programmed with the associated parameters.
Basic description
On change of the movement direction in the continuous-path mode contour transitions are
smoothed in that programmed positions are not approached exactly. In this way corners can
be moved round with as constant as possible speed or transitions can be optimized with
additional commands. With the exact stop function, machining operations can be
implemented as precisely as possible with inclusion of additional accuracy criteria. The
control determines the velocity control with look ahead automatically for several blocks in
advance.
For axes acceleration processes can be activated both conservatively for the mechanical
system or time-optimized. Both path axes and positioning axes, geo axes and following
axes, which can also change according to program run depending on the relevant blocks or
the momentary processing are discussed. The type of feedforward control and which path
axes should be operated with feedforward control can also be determined. In machining
without feedforward control the maximum permissible contour error can be specified.
A dwell time or a block with implicit preprocessing stop can be generated between two
blocks of the NC machining.
A programming example is given for each typical travel command.
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
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