Continuous-Path Mode; General Functionality - Siemens SINUMERIK 828D Function Manual

B1: Continuous­path Mode, Exact Stop, LookAhead

3.3 Continuous-path mode

3.3 Continuous-path mode
3.3.1

General functionality

Continuous-path mode
In the continuous-path mode the path velocity is not decelerated for the block change in order to permit the
fulfillment of an exact stop criterion. The objective of this mode is to avoid rapid deceleration of the path axes at
the block-change point so that the axis velocity remains as constant as possible when the program moves to the
next block. To achieve this objective, the "LookAhead" function is also activated when the continuous path mode
is selected.
Continuous­path mode causes the smoothing and tangential shaping of angular block transitions by local
changes in the programmed contour. The extent of the change relative to the programmed contour can be limited
by specifying the overload factor or rounding criteria.
Continuous­path operation causes:
• Contour rounding
• Shorter machining times through elimination of braking and acceleration processes that are required to
comply with the exact-stop criterion
• Improved cutting conditions because of the more constant velocity
Continuous­path mode is suitable if:
• A contour must be traversed as quickly as possible (e.g. with rapid traverse).
• The exact contour may deviate from the programmed contour within a specific tolerance for the purpose of
obtaining a continuous contour.
Continuous-path mode is suitable if:
• A contour is to be traversed precisely.
• An absolutely constant velocity is required.
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Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions