mesh relaxing with kangaroo

i want to control the minimum height of this mesh surface ("H" in the right view) and the depth of the "A" curve ("A" in top view). actually i want to increase the "H" and decrease the depth of the "A" curve. when i Increase the stiffness of the "A" curve (The edge of "A" curve) more than 5500, the mesh becomes wrong (picture below).

And when i decrease the stiffness of Crv1 And Crv2, it helps to decrease the depth of "A" curve but it causes to decrease the height ("H").

Thanks For Your Help.

I genuinely apologise for my terrible English. :D

Attachments:

mesh.gh, 8 KB
mesh.3dm, 29 KB

Replies to This Discussion

Permalink Reply by Jon Mirtschin on June 2, 2012 at 2:37am

Hi,

As you've asked, here's one approach at the relaxation using the StructDrawRhino solver.

You can use a 4 curved edge surface if you want the "A" arcs at the other edges.

Hope it helps,

Jon

Attachments:

mesh structdrawrhino.gh, 6 KB

Permalink Reply by Mahdiyar on June 2, 2012 at 2:42am

Thanks a lot Jon.

Permalink Reply by David Stasiuk on June 2, 2012 at 3:18am

Additionally, if you want to keep it in kangaroo, you can apply unary forces to the points along the edges in question...

Attachments:

mesh_update.gh, 13 KB

Permalink Reply by Mahdiyar on June 2, 2012 at 3:19am

Thank You So Much David.

Permalink Reply by Mahdiyar on June 2, 2012 at 5:07am

Jon first of all i should thank you so much for this useful guidance.

i want the "A" arcs at the other edges but i don't know how to use "4 curved edge surface". can you please show me how to do that?

Thank you!

Permalink Reply by Jon Mirtschin on June 2, 2012 at 5:32am

I'm checking the results obtained in the attached model. If I upload a new build of StructDrawRhino that's working better I'll let you know.

4 edge surface didn't work so well, a sweep 2 rail looks like a better option.

Attachments:

mesh structdrawrhino.gh, 13 KB

Permalink Reply by Mahdiyar on June 2, 2012 at 5:34am

Thank you let me check it.

Permalink Reply by Mahdiyar on June 2, 2012 at 5:46am

one more question Jon.

I have the GeomGym plugin installed on my grasshopper. but when i open the attachment file or when i open the example files (downloaded from your website). this message appears.

And the objects missing in the grasshopper.

Permalink Reply by Mahdiyar on June 2, 2012 at 5:54am

Thank you Jon it works perfect :) \m/

Permalink Reply by Daniel Piker on June 2, 2012 at 6:04am

To solve the stiffness issue, you can reduce the timestep (from 0.01 to 0.001)

but to reduce the horizontal depth while increasing the height you need some additional forces or constraints

What is the actual physical structure you are modeling ?

bear in mind that if this is a membrane structure where you want your 'A' curves to be flexible cables, then you cannot make them more vertical without some additional support (eg extra cables anchored to the ground pulling them outwards)

Permalink Reply by Mahdiyar on June 2, 2012 at 6:40am

Thanks Daniel

by reducing the "damping" to the 0, i can increase the stiffness to 8752. but i cant increase it more than that even if i change the time stamp. actually it seems that changing the time step didn't affect the stiffness. (pictures below)

Permalink Reply by Daniel Piker on June 2, 2012 at 6:45am

What you have changed there is the timer interval

The timestep is a setting accessed by either right clicking Settings on the Kangaroo component and choosing the Kangaroo Options dropdown menu, or by connecting a settings component (the spanner icon in the Kangaroo tab) to the Kangaroo settings input.