Siemens SINUMERIK 840D sl Function Manual page 278

B2: Acceleration
5.2 Functions
Substitute characteristic curve with curved path sections
In the case of curved path sections, normal and tangential acceleration are considered
together. The path velocity is reduced so that only up to 25 % of the speed-dependent
acceleration capacity of the axes is required for normal acceleration. The remaining 75 % of
the acceleration capacity is set aside for the tangential acceleration, i.e., deceleration/
acceleration on the path.
①
②
a
N
a :
ers
v
ers
r
Figure 5-11
Block transitions with continuous-path mode
If continuous-path mode is active, non-tangential block transitions result in axial velocity jumps
when the programmed path velocity is used for traversing.
As a result, the path velocity is controlled in such a way that prevents any axial velocity
proportion from exceeding the creep velocity v
Deceleration ramp with continuous-path mode and LookAhead
In the case of consecutive traversing blocks with short paths, an acceleration or deceleration
operation may be spread over several part program blocks.
In such a situation the "LookAhead" function also takes into account the parameterized speed-
dependent acceleration characteristic.
278
Normal range
Reducing range
Normal acceleration
Substitute characteristic curve constant acceleration
Substitute characteristic curve velocity
Path radius
Substitute path characteristic curve: Curved path
at the time of the block transition.
red
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions