Look-Ahead

The actual velocity at the segment transition depends on a range of parameters. These include residual path length, dynamic parameters for the current segment, and (indirectly) the geometric angle at the segment transition.

Dynamic look-ahead (referred to as look-ahead below) ensures that the velocity can remain as high as possible at segment transitions. In the standard configuration 128 geometry entries are considered.

Without look-ahead the velocity is reduced to 0 at each segment transition (G60).

Segments with different target velocity

If the target velocity changes from a high velocity level to a lower level (N10 -> N20), the lower velocity will already have been reached at the start of the segment.

If the target velocity changes from a low velocity level to a higher level (N20 -> N30), the higher velocity is initiated with the segment transition. The system therefore always ensures that even at the segment boundary the current velocity does not exceed the programmed velocity.

Look-Ahead 1:

Green: Path velocity
Blue: Position
Orange: Block numbers

N10 G01 X600 F30000
N20 G01 X700 F15000
N30 G01 X900 F30000
M30

Look-Ahead 2:

Green: Path velocity
Blue: Position
Orange: Block numbers

N40 G01 X200 F15000
N50 G01 X800 F30000
N60 G01 X900 F15000
M30