
TITLE
FANUC Series 16i/18i/21i-TB
AI nano contour control
Specifications
EDIT. DATE DESIG. DESCRIPTION
FANUC LTD
SHEET
12/37
DRAW. NO.
A-78962EN (2) is added. 2003.03.27 02
CUST.
♦ Setting a permissible acceleration change level
Parameter No.1788 is used to set a permissible acceleration change level for each axis. The permissible
acceleration change level is a rate per ms. If a parameter value is 0, speed control based on changes to
acceleration is not performed for the axis that corresponds to that parameter value.
(Example of parameter setting) (2)
In case of transition from liner interpolation to circle interpolation, such as in the following figure, if the
command feedrate ν is 6000mm/min and radius of circle
r
is 10mm, acceleration change for X-axis
becomes as follows:
2
2
/1000 smm
r
v
=
X
Z
X-axis
Acceleration
Acceleration
Time
Transition from liner interpolation
to circular interpolation
Feedrate 6000mm/min
Acceleration
change
1000mm/s
2
Radius 10mm
To keep this acceleration change below 300mm/s
2
, set 300mm/s
2
in the parameter No.1788 for X-axis.
However, acceleration change is calculated in interpolation unit in CNC, consequently calculated
acceleration change value might be different from theoretically value. And the actual tool machine
movement is influenced by acceleration/deceleration and so on, therefore adjust parameter setting value.