Tensile moving fabric model thing??

Hey there, im a diploma architecture student at Westminster and am relatively new to this stuff.

Im trying to create a grasshopper version of a model that ive built. It basically consists of a frame of fabric that can move up and down which is held in tension at certain points by strings.

I initially created a mesh, made the anchor points the 4 corners and centre point and applied kangaroo.(The top half of the grasshopper script)

I then tried to move the 4 corner points down, as with my physical model, but the mesh didnt move with the points.

I drew a line between the central point of the original rectangular mesh and the 4 downwards translated corner points.

I then created triangular mesh faces, rotated them, and joined them together to create a mesh pyramid.

I then tried to apply the same kangaroo method as the start, with the anchor points as the 4 base corners and the top point, and the geometry to be affected teh mesh pyramid, but i wasnt able to get it working and im not sure what im missing

Have you any idea where ive gone wrong, and also, do you have any suggestion as to how the script can be improved to behave more like my physical model, because to be honest im just making this up as i go along and havnt really got any sort of clue what im doing

Thanks,

Antony
Physical%20Model%20Test%201.gh P1060739.JPG

Replies to This Discussion

Permalink Reply by Yoann Mescam (Systemiq) on October 14, 2011 at 4:29pm

Does this look more realistic ?

Attachments:

PhysicalModelTest2.gh, 8 KB

Permalink Reply by Antony Joury on October 15, 2011 at 4:58am

Hey, thanks alot for the improved model, makes perfect sense now and much better than the way i was going about it. I just have one question, instead of having a single force acting up on the central point whilst the boundary points are held in place, is it possible to have the reverse. As in can the boundary points have a force acting on them so they move vertically downwards by a certain amount whilst the central point is held in position?

Thanks again for the help

Permalink Reply by Yoann Mescam (Systemiq) on October 15, 2011 at 4:25pm

I think it would look the same. I tried to do it, I can make the boundary points fall while maintaining them on a linear track, but I cant keep them in a frame shape.

Perhaps someone more skilled than me would know how to do it, I failed trying bend resistances, more springs, etc to keep the frame points correctly aligned.

Attachments:

PhysicalModelTest3.gh, 8 KB

Permalink Reply by Antony Joury on October 16, 2011 at 8:18am

Ok, thanks for the help, very much appreciated

Permalink Reply by Yoann Mescam (Systemiq) on October 16, 2011 at 3:14pm

I think the key to a rigid frame is using good springs with very high stifness, but very high stifness values tend to make the model explode, tried some settings from http://www.grasshopper3d.com/group/kangaroo/forum/topics/rigid-frames but no success so far.

RSS