How to identify the internal/external faces of an open cube ?

How to identify the internal/external faces of an open cube ?

michelmarroche
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How to identify the internal/external faces of an open cube ?

michelmarroche
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Hello, I am creating a simple object to then perform operations on it... I have managed to identify the external faces, top, bottom, front, back, left and right... but I don't know what would be the best way to identify the opposite interior faces to the exteriors

 

michelmarroche_0-1715045167774.png

 

 

Could you recommend me any technique for this?

 

Thank you

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BrianEkins
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 Without fully understanding your requirements, I'm not sure what will be best, but I would look at the findBRepUsingRay method.

---------------------------------------------------------------
Brian Ekins
Inventor and Fusion 360 API Expert
Website/Blog: https://EkinsSolutions.com
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michelmarroche
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Thanks Brian, I'm going to look at this method, I didn't know...

 

What I am trying to do is the following:

 

- I create a sketch
- extruded the same
- I apply a shell
- and now I need to apply a split body to the inner faces separately

 

michelmarroche_2-1715130535773.png

 

 

With this I generate a module assembled by bodies (plates in my case)

 

That's why I need to be able to identify each of the internal faces of the cube. I am already identifying the exteriors according to their axis.

 

This is how it would look after applying the split bodies..

 

michelmarroche_0-1715130475494.png

michelmarroche_1-1715130491465.png

 

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Message 4 of 5

BrianEkins
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Accepted solution

Your picture doesn't look like a shelled cube but instead like five thin blocks put together to make a cube shape. If it is a block that's been hollowed out with a Shell feature and the shell is to the inside, you can use the faces property of the ShellFeature, and it will return the five created by the shell, which are the inside faces.

 

You can also iterate over the surfaces and get their normals. The normals of the outside faces will be the same as the inside faces. for example, the normal of the left inside face will be the same as the right outside face, but since you already have the right face, you can eliminate it from the list, and you'll be left with the inside faces. You could also traverse the topology of the solid to get to the inside faces. It's really a bit of a puzzle to figure out something that will work and then continue to look for something that is either simpler or more efficient, or ideally both.

---------------------------------------------------------------
Brian Ekins
Inventor and Fusion 360 API Expert
Website/Blog: https://EkinsSolutions.com
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Message 5 of 5

michelmarroche
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Excellent idea to use the face normals to compare them and thus be able to identify them!

 

I am trying with the "findBRepUsingRay" method, although I am getting the result, I have not yet been able to interact with this result to extract which face I am coming across.

 

I'll try the normal ones... thanks again Brian !

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