7. With the moment of inertiaGD
2
Calculation formula
7. With the moment of inertiaGD
2
Calculation formula
Symbol description and unit
7.1 Calculation of turning radius K
K
2
=r
1
2
/2[m]
K
2
=
K=
r
1
：Distance from the axis of rotation (radius of the rotating body)[m]
K
2
=(r
1
2
+r
2
2
)/2[m]
K
2
=
K=
r
1
：Distance from the axis of rotation (outer diameter of the rotating body))[m]
r
2
： Distance from the axis of rotation (inner diameter of the rotating body) [m]
K
2
=(a
2
+b
2
)/3[m]
K
2
=
K=
a： Distance from the axis of rotation (length of rotating body / 2) [m]
b： Distance from the axis of rotation (width of rotating body / 2) [m]
K
2
=r
1
2
/2+R
2
[m]
K
2
=
K=
r
1
：Radius of rotating body [m]
R： Distance from the axis of rotation [m]
K
2
=(r
1
2
+r
2
2
)/2+R
2
[m]
K
2
=
K=
r
1
： Outer diameter of rotating body [m]
r
2
： Inner diameter of rotating body [m]
R：Distance from the axis of rotation [m]
K
2
=(a
2
+b
2
)/3+R
2
[m]
K
2
=
K=
a：Length of rotating body / 2 [m]
b：Width of rotating body / 2 [m]
R： Distance from the axis of rotation [m]
7.2 Calculation of moment of inertia I
(1) Moment of inertia I
SI Unit system
I=m*K
2
[kg･m
2
]
I=
m： Mass of rotating body [kg]
K： Radius of gyration [m]
(2) Moment of inertia I
Gravitational metric system
I=W/g*K
2
[kgf･ms
2
]
I=
g=9.8m/s
2
：Gravitational acceleration
W：Weight of rotating body [kgf]
K： Radius of gyration [m]
7.3 GD
2
Calculation
(1)GD
2
GD
2
=4*I*g [kgf･m
2
]
GD
2
=
g=9.8m/s
2
： Gravitational acceleration
I： Moment of inertia[kgf･ms
2
]
The moment of inertia is the product of the square of the radius of gyration of an object and the mass of that object, and the moment of inertia expressed by I = mK
2 is Represents an object with mass m placed at the position of radius of gyration K.
On the other hand, the conventionally used "GD
2 " is a method of expressing the moment of inertia in the gravitational unit system, where G is the weight of the object W (= mg), D (= 2K) represents the diameter of rotation. The relationship between the moment of inertia I of the gravitational unit system and GD
2 is that g is the gravitational acceleration. I = mK
2 = (W / g) K
2 = GD
2 / 4g (kgf ･ ms
2 )It looks like。