Harmonic Drive RSF Series, Руководство пользователя

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Appendix 2 Calculations of moment of inertia
RSF-super_V1_02
- Appendix 2-2 -
Shape of object
Mass, inertia,
position of center of gravity
Shape of object
Mass, inertia,
position of center of gravity
m s ir p n o g a x e h r a l u g e R m s ir p c i b m o h R
Equilateral triangular
prism Right-angled triangular
prism
Example of specific gravity
The following table shows informative values of specific gravity. Please check actual specific gravities of
materials individually.
Material Specific gravity Material Specific gravity Material Specific gravity
SS45C 7.86 Brass 8.5 Epoxy resin 1.9
1 . 1 S B A 7 . 2 m u n i m u l A 5 8 . 7 C 1 4 S S
Cast steel
7.85 Duralumin 2.8 Silicone resin 1.8
Cast iron 7.19 Teflon 2.2 Urethane rubber 1.25
Copper 8.92 Fluorine resin 2.2 Chloroprene rubber 1.15
(2) When center of revolution and line of center of gravity do not match
Moment of inertia when axis of center of gravity and axis of revolution of an inertia field do not match is
calculated by the following formula.
I: Moment of inertia when axis of center of gravity and axis of
revolution do not match (kgm
2
)
Ig: Moment of inertia when axis of center of gravity and axis of
revolution match (kgm
2
)
Calculated by formula shown in (1) in accordance with shape.
m: Mass (kg)
F: Distance between axis of revolution and axis of center of gravity (m)
(3) Moment of inertia of linear motion object
The moment of inertia converted into an RSF-supermini actuator axis of a linear motion object driven
by a screw is calculated by the following formula.
I: Moment of inertia converted into actuator axis of a linear motion object (kgm
2
)
m: Mass (kg)
P: Amount of linear movement per revolution of actuator (m/rev)
Axis of
revolution
Axis of center
of gravity
F
ρ
ABC
2
1
m =
+ =
2
2
C
3
2
2
B
m
12
1
Ix
+ =
2 2
C
3
2
A m
12
1
Iy
+ =
2
B
A m
12
1
Iz
2
2
3
C
G =
G
z
x
y
B
A
C
G
1
z
x
y
B
A
G
2
C
ABC
ρ
2
1
m =
(
)
2 2
C B m
36
1
Ix + =
+ =
2 2
C
3
2
A m
12
1
Iy
3
C
G
1
=
+ =
2 2
B
3
2
A m
12
1
Iz
3
B
G
2
=
z
x
y
C
A
B
ABC
2
1
m =
( )
2 2
C B m
24
1
Ix + =
( )
2 2
2A C m
24
1
Iy + =
( )
(
)
( )
2 2
2A B m
24
1
Iz + =
z
x
y
B
B √ 3
A
2
B m
12
5
Ix =
+ =
2 2
B
2
5
A m
12
1
Iy
+ =
2 2
B
2
5
A m
12
1
Iz
AB
2
3 3
2
= m
2
mF Ig I + =
2
2
P
m I
π
=
( )
( )
(
)
( )
(
)
ρ
ρ