Epson SCARA GX Series, Manual

Page: 167 / 236

GX8 Manipulator 4. Setting of End Effectors
GX series Rev.2 157
Calculating the Moment of Inertia
Refer to the following examples of formulas to calculate the moment of inertia of load (end
effector with work piece).
The moment of inertia of the entire load is calculated by the sum of each part (a), (b), and
(c).
Work piece (b)
Work piece (c)
End effector (a)
Joint #3 shaft
Rotation center
Moment of inertia
of end effector (a)
=
Moment of inertia
of work piece (b)
+
Moment of inertia
of work piece (c)
+
Whole moment
of inertia
The methods for calculating the moment of inertia for (a), (b), and (c) are shown below.
Calculate the total moment of inertia using the basic formulas.
(a) Moment of inertia of a rectangular parallelepiped
h
b
L
m
Rectangular parallelepiped’s center of gravity Rotation center
m + m × L 2
b 2 + h 2
12
(b) Moment of inertia of a cylinder
m + m × L 2
r
2
2
m
L
r
Cylinder’s center of gravity
Rotation center