linear edge restrains on a partial sphere?

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Permalink Reply by Michael Freytag on October 9, 2013 at 2:55pm

Morgana,

Can you show us a screenshot of your geometry and how you'd like to restrain it?

Thanks,

Michael

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Permalink Reply by Morgana Arbore on October 10, 2013 at 3:59am

I'd like to restrain only the circle, not the surface...

the depth of the sherical dome is 2 cm (then I would get a "membrane behavior" without flexion)

Wich restrains condition should I use? 

Thanks,

Morgana 

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Permalink Reply by Michael Freytag on October 10, 2013 at 1:50pm

Morgana,

Here's a little trick that might approximate what you are looking for:

1. Split the outer face (Rhino: Solid > Solid Edit Tools > Faces > Split Face) so there is a narrow band to which a Z-only restraint can be applied.
2. In Scan&Solve:
   1. Apply a restraint to this band then choose [Edit] to free the X and Z directions.
   2. Apply a restraint to the bottom planar ring then choose [Edit] to free the Z direction.
   3. Proceed with applying your loads, specifying a resolution, and choose [GO!].

This arrangement of restraints will allow small rotations about the outer edge, but you must choose a high enough resolution to have sufficient degrees of freedom to allow the rotation.  Turn on the grid display and try to get three elements through the thickness.

You can also effectively increase the available resolution by exploiting the symmetry of the model, quartering it, and applying partial restraints on the cut faces:

In this case, the bottom edge will be free to "slide" on the XY-plane.  This may or may not be what you are after.

Does this help?

~Michael

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Permalink Reply by Morgana Arbore on October 11, 2013 at 10:15am

oooooh!!! yes!! 
Thank you so much! :)

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