
In transition of linear interpolation R
circular interpolation, speed control
is performed based on a permissible
acceleration change level set in
parameter No.1788.
Linear
interpolation
Circular
interpolation
If linear interpolation is repeated,
speed control is performed based on
a permissible acceleration change
level set in parameter No.1789.
Linear
interpolation
TITLE
FANUC Series 16i/18i/21i-TB
AI nano contour control
Specifications
EDIT. DATE DESIG. DESCRIPTION
FANUC LTD
SHEET
13/37
DRAW. NO.
A-78962EN (2) is added. 2003.03.27 02
CUST.
♦
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.1789 can increase the cutting speed.
If a nonzero value is specified in parameter No.1789 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.1788 is effective.)
For an axis for which parameter No.1789 is 0, a setting of parameter No.1788, that is, an ordinary
permissible acceleration change level, becomes effective also for corners where linear interpolation is
repeated.