Area moment of inertia

Hello
I am totaly new to this
I am using this component to get the moment of inertia of this cross section(three layers of lath) , but the result is two , should i add them to get the total I ?

I can’t see enough of your code to tell why there are only two points for “three layers of lath” but you probably want to use Average to get the midpoint between two points. As to moment of inertia, that would assume both have the same area… (or volume?).

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Hello Joseph
Thank you for your reply, Now I think i got the mistake i was doing, i was expecting to get one point since i did region union to these curves but they were resulting 2 curves.
If i am going to bend the lath about the shown direction, then i should only use the x component of the inertia ?

Region union for three boxes that don’t touch each other? Sounds like you’re on the wrong track but without posting your code, I can’t tell. If it requires a plugin, I probably won’t be able to help you anyway.

3. Attach minimal versions of all the relevant files

They are actually 5 curves, so the two inbetween curves are connecting them.
The three laths are not touching each other because in reality this space between them at some points is for the other direction of laths.
Inertia.gh (12.8 KB)

I see… I’ve never heard of AMoments (Area Moments) so can’t help you with that, but it looks like RUnion worked as expected and the AMoments ‘C’ (Centroid) is the same as that returned by the Area component.

The ‘I’ (Inertia) output that you are deconstructing as a point is actually a vector, as are all the outputs except the first two, ‘A’ and ‘C’…

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Alright, thank you!

Hi @dai_kandeel,

I would apply the parallel axis theorem in this case, using the individual moments and then adding their difference from the centroid squared times the area.
parallel Axis Theorem.gh (6.6 KB)

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Thank you so much!