How to assemble a flat part to a round part?

[user.user.user.user]

Hi,

probably Inventor is not the perfect program for what I#d like to do, but I don't know a better way.

What I'd like to do is that I have to parts (a flat cylinder) and a hemisphere and I want to positon the cylinder with its flat ground tangentially to the hemisphere.

Why I want to do this is because in reality my cylinder beams rays and I'd like to simulate what the effect of changing the position on the hemisphere is regarding its field of rays in the inside of the hemisphere.

I don't know yet how I will to the thing with the rays, but for now I am interested in knowing wheather I can attache my cylinder to the hemisphere to then move it around over its surface.

Thanks for help

[leowarren34]

You can tangentially constrain parts together in assembly mode.

So tangentially constrain the cyclinder to the round surface of the hemisphere.

[user.user.user.user]

Thanks for the fast answer!

I tried that but then I can move the part in the level that touches the hemisphere in one point tangentially, but not around the whole hemisphere.

[SBix26]

As @leowarren34 says, use Tangent constraint.  But you will need more than just the tangent constraint, as this only removes one degree of freedom.  What other constraints are there on the movement of the hemisphere?  Does it remain in the same orientation, or on the same centerline, for example?

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Sam B
Inventor Pro 2020.1.1 | Windows 7 SP1
LinkedIn

[leowarren34]

If you ground the cylinder and go into the iproperties and the occurence you should see a degree of freedom tick box, tick it to display deg of freedom.

[user.user.user.user]

hm...I am quite thankful for your answers, but I think I didn't manage to express my problem understandably, sorry.

I want the cylinder to have some degrees of freedom open, as I want to move it arount on the surface of the hemisphere. The only constreint, that I want to have is that no matter to which point on the surface of the hemisphere I am moving the cylinder, I want it to lay tangentially touching the hemisphere only with the middle point of the flat surface of the cylinder.

[SBix26]

What version of Inventor are you using?  Can you attach your files here (.zip)?

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Sam B
Inventor Pro 2020.1.1 | Windows 7 SP1
LinkedIn

[leowarren34]

So ground the hemisphere and constrain the cylinder until the required number of degrees of freedom are achieved.

[user.user.user.user]

Yes but I don't know how to do the constraints I need or if they are actually possible...

[user.user.user.user]

Yes, I hope that works...

[SBix26]

Mate constrain the axis of the cylinder to the center point of the hemisphere, then tangent constrain the face of the cylinder to the face of the hemisphere.

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Sam B
Inventor Pro 2020.1.1 | Windows 7 SP1
LinkedIn

[AdamAG99T · Accepted solution]

I believe you should be able to accomplish this with a Transitional constraint between the hemisphere and flat face of the cylinder, and with a mate constraint between the center axis of the cylinder and the center point of the hemisphere.

[user.user.user.user]

hm, sorry, i think i still couldn't explain my problem correctly, but thats my fault...

The constraints you are proposing i what i could get everytime I tried it but it is not what I want. What I want would be the constraint that the point in the middle of the flat surface of the cylinder always touches the hemisphere and canbe moved around on its surface...but maybe that is just not possible...

Anyway, thanks for all your answers and trying to explain it to me several times.

[AdamAG99T]

Is there any way you could share your files? Make sure you zip them since the forum is unable to upload inventor files without them being zipped. I'm not sure how the assembly I shared in my post differs from what you're trying to accomplish. See the attached screencast for a quick example of the motion if you are unable to open my assembly. 

https://knowledge.autodesk.com/community/screencast/21da314e-082f-48c1-8a0b-f788d62599ab

[SBix26 · Accepted solution]

Does this help?

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Sam B
Inventor Pro 2020.1.1 | Windows 7 SP1
LinkedIn

[user.user.user.user]

Ok, thanks both of you, both screencasts were very helpful and you were right, that was exactly what I was looking for.

Thanks a lot for your help!