
Linear interpolation (N1) → circular interpolation (N2)
X
Z
Vibration due to changes to
acceleration
N1
N2
Tangential
speed
X-axis
acceleration
Speed
Time
N1
N2
Time
Speed
cceleration
Time
cceleration
Time
Speed control based on changes to
acceleration is not effective
Speed control based on changes to
acceleration is effective
2.9 Jerk control
(The option for jerk control is required.)
There are two types of jerk control functions as described below.
(1) Speed control based on changes to acceleration for each axis
(2) Look-ahead smooth bell-shaped acceleration/deceleration before interpolation
(1) Speed control based on changes to acceleration for each axis
Vibration or shocks may occur to the machine in portions where there is a large change to acceleration, for
example, a portion where the shape specified by the machining program changes from a straight line to a
curved line.
To reduce machining error that may result from vibration or shocks to the machine when the acceleration
changes, speed control based on changes to acceleration for each axis reduces the tool speed at
acceleration/deceleration before interpolation by obtaining a feed rate that can keep acceleration changes
from exceeding the permissible acceleration change level set in parameters for each axis.
TITLE
FANUC Series 16i/18i/21i-TB
AI nano contour control
Specifications
EDIT. DATE DESIG. DESCRIPTION
FANUC LTD
SHEET
11/37
DRAW. NO.
A-78962EN (2) is added. 2003.03.27 02
CUST.
♦ Example
The following example performs deceleration at a point of tangency between linear interpolation and
circular interpolation because there is a large change to acceleration along the X-axis.