Robotics User Manual

3-28
CHAPTER 3 Installation
2) Moment of inertia of the chuck
When the chuck form resem-
bles that shown in Fig. 3-21,
the weight of the chuck (Wc)
is
Wc = 0.0078 × 2 × 4 × 6
= 0.37 (kgf)
The moment of inertia of the
chuck (Jc) is then calculated
from Eq. 3-7.
Jc =
0.37 × (2
2
+4
2
)
12 × 980
0.37 × 10
2
+
980
= 0.038 (kgfcmsec
2
)
Fig. 3-21
10cm
2cm
6cm
4cm
R-axis
3) Moment of inertia of workpiece
When the workpiece form
resembles that shown in Fig.
3-22, the weight of the
workpiece (Ww) is
Ww =
ρπD
2
h
=
0.0078π × 2
2
× 4
44
= 0.098 (kgf)
The moment of inertia of the
workpiece (Jw) is then calcu-
lated from Eq. 3-5.
Jw=
0.097 × 2
2
+
0.097 × 10
2
8 × 980 980
= 0.010 (kgfcmsec
2
)
Fig. 3-22
10cm
4cm
R-axis
2cm
4) Total weight
The total weight (W) is calculated as follows:
W = Ws + Wc + Ww = 0.84 (kgf)
5) Total moment of inertia
The total moment of inertia (J) is then obtained as follows:
J = Js + Jc + Jw = 0.062 (kgfcmsec
2
)