Velocity Reduction According To Overload Factor - Siemens SINUMERIK 828D Function Manual

B1: Continuous­path Mode, Exact Stop, LookAhead
3.3 Continuous-path mode
3.3.2

Velocity reduction according to overload factor

Function
The function lowers the path velocity in continuous­path mode until the non­tangential block transition can be
traversed in one interpolation cycle while respecting the deceleration limit and taking and overload factor into
account.
With the reduced velocity, axial jumps in velocity are produced with a non­tangential contour at the block
transition. These jumps in velocity are also performed by the coupled motion synchronized axes. The jump in
velocity prevents the path velocity dropping to zero. This jump is performed if the axial velocity was reduced with
the axial acceleration to a velocity from which the new setpoint can be reached with the jump. The magnitude of
the setpoint jump can be limited using an overload factor. Because the magnitude of the jump is axial, the
minimum jump of the path axes which are active during the block change is considered during block transition.
Figure 3-3 Axial velocity change on block transition
With a practically tangential block transition, the path velocity is not reduced if the permissible axial accelerations
are not exceeded. This means that very small bends in the contour (e.g. 0.5 degrees) are overtraveled directly.
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Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions