Detailed description
2.3 Continuous -path mode
Basic logic functions: Continuouspath Mode, Exact Stop, LookAhead (B1)
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Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Smoother path movement
If the velocity is controlled smoother and not every acceleration process is carried out, both
advantages can be achieved without any undesired extended machining time.
Decision-making criteria
The control system makes a decision based on:
•
Smoothing frequency for the tool path velocity (MD)
•
Tolerable loss in productivity when suppressing accelerations/decelerations (MD).
Setting parameters for path smoothing
The user can define the following parameters to set the path smoothing:
•
Extending the processing time by means of machine data:
MD20460 $MC_LOOKAH_SMOOTH_FACTOR (smoothing factor for LookAhead)
If the velocity is not accelerated, it will take longer to process this part program (see
example).
•
Use of the machine data to input the resonance frequencies of the participating axes:
MD32440 $MC_LOOKAH_FREQUNECY (smoothing frequency for LookAhead)
Only accelerations in velocity, which clearly excite machine resonances, should be
removed.
•
Use of machine data to take into account the programmed feedrate for smoothing:
MD20462 $MC_LOOKAH_SMOOTH_WITH_FEED (path smoothing with programmed
feedrate)
MD20460
A percentage value corresponding to the permissible extension must be specified in machine
data:
MD20460 $MC_LOOKAH_SMOOTH_FACTOR (smoothing factor for LookAhead)
The percentage value defines how much longer a machining step without accelerations may
be than the corresponding step when performing the accelerations/decelerations.
This would be a "worst-case" value, if all accelerations within the part program, except the
initial approach motion, were smoothed.
The actual extension will always be smaller, and may even be 0, if the criterion is not met by
any of the accelerations.
Values between 50 and 100% may also be entered without significantly increasing the
machining time.
Summary of Contents for SINUMERIK 840D sl
Page 282: ...Index Basic logic functions Acceleration B2 64 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Page 388: ...Basic logic functions Travel to fixed stop F1 Function Manual 11 2006 6FC5397 0BP10 2BA0 52 ...
Page 962: ...Index Basic logic functions Emergency Stop N2 20 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Page 1704: ...Constraints Basic logic functions Spindles S1 94 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Page 1716: ...Index Basic logic functions Spindles S1 106 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Page 1996: ...Index Basic logic functions Tool Offset W1 208 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Page 2150: ...Table of contents Basic logic functions Appendix 4 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Page 2184: ...Glossary Basic logic functions Appendix 38 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...