# FANUC Series 16/18/160/180-Model C Machining Center Operators Manual PROGRAMMING
14. FUNCTIONS TO SIMPLIFY
PROGRAMMING
B–62764EN/01
242
Coordinate conversion about an axis can be carried out if the center of
rotation, direction of the axis of rotation, and angular displacement are
specified. This function is very useful in three–dimensional machining
by a die–sinking machine or similar machine. For example, if a program
specifying machining on the XY plane is converted by the three–
dimensional coordinate conversion function, the identical machining can
be executed on a desired plane in three–dimensional space.
X
Y
Z
Z
Y
X
Three–dimensional coordinate conversion
G68 Xp x
1
Yp y
1
Zp z
1
I
i1
J j
1
K k
1
R
α
; Starting three–dimensional
coordinate conversion
G69
Three–dimensional coordi-
nate conversion mode
Canceling three–dimensional
coordinate conversion
Xp, Yp, Zp: Center of rotation (absolute coordinates) on the X, Y, and Z
axis or parallel axes
I, J, K : Direction of the axis of rotation
R : Angular displacement
N1 G68 Xp x
1
Yp y
1
Zp z
1
I i
1
J j
1
K k
1
R α ;
N
2 G68 Xp x
2
Yp y
2
Zp z
2
I i
2
J j
2
K k
2
R β ;
Three–dimensional coordinate conversion can be executed twice.
In the N1 block, specify the center, direction of the axis of rotation, and
angular displacement of the first rotation. When this block is executed,
the center of the original coordinate system is shifted to (x
1
, y
1
, z
1
), then
rotated around the vector (i
1
, j
1
, k
1
) by angular displacement
α
. The new
coordinate system is called X’Y’Z’. In the N2 block, specify the center,
direction of the axis of rotation, and angular displacement of the second
rotation. In the N2 block, specify coordinates and the angle with the
coordinate system formed after the N1 block in Xp, Yp, Zp, I, J, K, and
R. When the N2 block is executed, the X’Y’Z’ coordinate system is
shifted to (x
2
, y
2
, z
2
), then rotated around the vector (i
2
, j
2
, k
2
) by angular
displacement
β
. The newest coordinate system is called X’’Y’’Z’’. In the
14.10
THREE–
DIMENSIONAL
COORDINATE
CONVERSION
(G68, G69)
Format
Explanations
D Command for
three–dimensional
coordinate conversion
(program coordinate
system) 