"deflation"

Replies to This Discussion

Permalink Reply by pb on December 9, 2011 at 3:30pm

yes, it`s a negative pressure, respectively the vector points inwards the volume you want to evacuate.

I think you have to deal with two options:

1) your structure have a bending stiffness (for instance a steel box) and is strong enough to resist.

than you will see only bending deformations which lead not to a form finding process. 

2) your structure have only axial stiffness (spring forces, for instance a textile) and the pressure you put onto it results in compression forces in the structure. this is not possible for textiles (they can hold tension only). It´s only possible for perfect arches or spheres out of materials which can take compression (stone, bricks, concrete..).

in kangaroo it`s very difficult to build compression only structures without (at least a little) bending-stiffness. this is because there are stability-problems respectively buckling of the structure.

hope this helps a little

pb

Permalink Reply by Michele Versaci on December 9, 2011 at 3:57pm

thank you very much pb!

i have to use the textile material. So if I understand correctly I can not simulate the textile, right?

Michele

Permalink Reply by pb on December 9, 2011 at 4:18pm

not necessarily

a structure like this can do it:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

blue: textile

red: compression elements

black: pressure, respectively partial vacuum

 

pb

 

 

Permalink Reply by Michele Versaci on December 9, 2011 at 4:32pm

great!

so, i have to set a negative pressur on the blue line (the textile)

i'm going to try!

thank you very much