
B-63783EN-1/01 7.FEEDRATE CONTROL/ACCELERATION AND DECELERATION CONTROL
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Continuous linear interpolation
In speed control based on acceleration changes in continuous linear
interpolation, the deceleration speed is obtained from changes to
acceleration between the start and end points of a command block.
When a machining program specifies a curved shape using continuous
very small line segments, the machining program approximates the
shape with a polygonal line because it rounds off specified values to the
least input increment.
This rounding error makes acceleration changes larger and therefore
can prevent the cutting speed from increasing especially in short blocks
because of frequent reductions in speed.
If this is the case, setting a larger permissible acceleration change level
for each axis for repeated linear interpolation in parameter No. 1674
can increase the cutting speed.
If a nonzero value is specified in parameter No. 1674 for axes for which
speed reduction based on acceleration changes are effective, the setting
becomes a permissible acceleration change level for corners where
linear interpolation is repeated. (Between linear interpolation and
circular interpolation operations and between circular interpolation
operations, a setting of parameter No. 1673 is effective.)
For an axis for which parameter No. 1674 is 0, a setting of parameter
No. 1673, that is, an ordinary permissible acceleration change level,
becomes effective also for corners where linear interpolation is
repeated.
If smooth speed control is used as speed control based on the
permissible acceleration for fine HPCC, the deceleration speed is
obtained from a acceleration change calculated in smooth speed
control.
For this reason, the deceleration speed can become higher compared
with the ordinary permissible acceleration change level.
In transition of linear interpolation R
circular interpolation, speed control
is performed based on a permissible
acceleration change level set in
parameter No. 1673.
Linear
interpolation
Circular
interpolation
If linear interpolation is repeated,
speed control is performed based on
a permissible acceleration change
level set in parameter No. 1674.
Linear
interpolation