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What is the mass moment of inertia about the longitudinal axis of the shape attached in this thread, but in 3 D?
I found this "Handbook of Equation for Mass and Area Properties of Various Geometrical Shapes" which gives the mass moment of inertia of a regular octagon. I initially thought that I will use that same equation and simply divide it by 2. However, I realized a couple of issues:
1. The equation given is for a 2D shape, and I need an equation for a 3D shape
2. The shape that I have attached with this thread, is not purely half an octagon, as for an octagon, all the sides are equal, and in this shape all of the sides are not equal (Please see the attachment)
3. I need the mass moment of inertia about the longitudinal axis only
So yeah, this is not easy as there is no equation available online that applies to what I want. Can anyone help me? Do you have any idea how I can find the mass moment of inertia for this shape in 3D? Thank you
I found this "Handbook of Equation for Mass and Area Properties of Various Geometrical Shapes" which gives the mass moment of inertia of a regular octagon. I initially thought that I will use that same equation and simply divide it by 2. However, I realized a couple of issues:
1. The equation given is for a 2D shape, and I need an equation for a 3D shape
2. The shape that I have attached with this thread, is not purely half an octagon, as for an octagon, all the sides are equal, and in this shape all of the sides are not equal (Please see the attachment)
3. I need the mass moment of inertia about the longitudinal axis only
So yeah, this is not easy as there is no equation available online that applies to what I want. Can anyone help me? Do you have any idea how I can find the mass moment of inertia for this shape in 3D? Thank you
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