Feedrate Optimization For Curved Path Sections (Cftcp, Cfc, Cfin) - Siemens Sinumerik 840D sl Programming Manual

Example:
Program code
...
N20 POS[V]=90 FDA[V]=0
Direction of movement, travel velocity
The axes follow the path set by the handwheel in the direction of the sign. Forward and
backwards travel is possible dependent on the direction of rotation. The faster the handwheel
rotates, the higher the traversing speed.
Traversing range:
The traversing range is limited by the starting position and the programmed end point.
Traverse positioning axis with velocity override (FDA[<axis>]=<velocity>)
In NC blocks with programmed FDA[...]=..., the feedrate from the last programmed FA value
is accelerated or decelerated to the value programmed under FDA. Starting from the current
feedrate FDA, the handwheel can be turned to accelerate the programmed movement to the
target position or decelerate it to zero. The values set as parameters in the machine data serve
as the maximum velocity.
Example:
Program code
N10 POS[V]=... FA[V]=100
N20 POS[V]=100 FAD[V]=200
Traversing range:
The traversing range is limited by the starting position and the programmed end point.
8.9

Feedrate optimization for curved path sections (CFTCP, CFC, CFIN)

With activated offset mode G41/G42, the programmed feedrate for the milling cutter radius
initially refers to the milling cutter center path (see Section "Coordinate transformations
(frames)").
When you mill a circle (the same applies to polynomial and spline interpolation) the extent to
which the feedrate varies at the cutter edge is so significant under certain circumstances that
it can impair the quality of the machined part.
Fundamentals
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
8.9 Feedrate optimization for curved path sections (CFTCP, CFC, CFIN)
Description
; Target position = 90 mm, axial feedrate = 0 mm/min and
path override with handwheel.
; Velocity of axis V at start of block = 0 mm/min.
; Path and speed defaults are set using handwheel pulses
Description
; Axial feedrate = 100 mm/min
; Axial target position = 100, axial feedrate = 200 mm/min
; and velocity override with handwheel.
; Acceleration from 100 to 200 mm/min in N20. The
; Handwheel can be used to vary the velocity depending on the direc-
tion of rotation
; between 0 and the maximum value (machine data).
Feed control
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