
PROGRAMMING22. RISC PROCESSOR
B–63534EN/02
674
Y
Z
X
P
R
e2
e1=V
T
V
D
Q
e3
Fig. 22.5.1 (j) Compensation vector calculation
In above figure, cutter compensation vector VD at point Q is calculated
as follows :
(1) Calculating the tool vector (VT)
(2) Calculating the coordinate conversion matrix (M)
Coordinate systems are defined as follows :
– Coordinate system C1 : {O; X, Y, Z}
Cartesian coordinate system whose fundamental vectors are the
following unit vectors along the X–, Y–, and Z–axes :
(1, 0, 0)
(0, 1, 0)
(0, 0, 1)
– Coordinate system C2 : {O; e2, e3, e1}
Cartesian coordinate system whose fundamental vectors are the
following unit vectors :
e2
e3
e1
where, e2, e3, and e1 are defined as follows :
e1 = V
T
e2 = b2 / |b2| , b2 = a2 – (a2,e1)– e1
e3 = b3 / |b3| , b3 = a3 – (a3,e1)– e1 – (a3,e2)– e2
a2 is an arbitrary vector linearly independent of e1, and
a3 is an arbitrary vector linearly indepen dent of e2 and e1.
The coordinate conversion matrix M from coordinate system C1 to
C2, and the coordinate conversion matrix M
–1
from coordinate system
C2 to C1 are expressed as :
M +
ƪ
e2
e3
e1
ƫ
, M
–1
+ (
t
e2
t
e3
t
e1)
D Compensation vector
calculation