diagrid structure member sizes

I have a diagrid structure which will be made of wood. For this reason the members will get smaller per floor as it goes upward. For instance the tower on the left has 19 floors, so the diagrid members on the first floor need to be 19x larger than the top floor. each floor that goes up gets 1x smaller. How can I do this parametrically?

Attachments:

design exploration.3dm, 193 KB
GH.jpg, 674 KB

Replies to This Discussion

Permalink Reply by Ryan Gathmann on March 19, 2013 at 9:43pm

Do you have the grasshopper file you are working with?

Permalink Reply by Brian on March 20, 2013 at 12:28pm

do you know a simplified way to do this?

Permalink Reply by Brian on March 19, 2013 at 10:01pm

Oops, here it is

Attachments:

Design exploration.ghx, 250 KB

Permalink Reply by David Stasiuk on March 20, 2013 at 2:58am

Hey there...I went perhaps a bit overboard (a nice morning exercise!) But anyway, I'd suggest that you take a mesh-based approach...it will be a lot simpler and lighter to implement than doing surface piping, and weaverbid has some wonderful tools for varying both "window" face-offsets as well as mesh thickening, so you'll be able to get integrated variable thicknesses in a single, unified mesh. (you can get it here if you don't have it: http://www.giuliopiacentino.com/weaverbird/)

The first part of the definition is just the volume construction...you should replace your strategy here. Then you use lunchbox to get your diagrid lines, and feed them into weaverbird's mesh from line component. After that, you can see that picture frame tool can be fed variable levels for each mesh edge. By measuring the mesh edge's Z value relative to the rest of them, you can dynamically vary the thickness of the picture frame as you go up the mesh. Then you do pretty much the same thing for thickening the mesh...but here you do it for each mesh vertex, which acts as an input to the weaverbid thicken mesh tool. If you have to have your geometry as nurbs, it's really easy to convert back from here, as each mesh face is a quad.

Attachments:

diagrid_shift.gh, 14 KB

Permalink Reply by Brian on March 20, 2013 at 11:11am

looks good but I'll have to attempt to get my shape into that script. thank you

Permalink Reply by Brian on March 20, 2013 at 12:30pm

trying to weed out the scripts i dont need... and combine it with my current version. Is there a more simplified way to do this with my current geometry?

Permalink Reply by David Stasiuk on March 20, 2013 at 1:01pm

just start from the surface...replace it with yours...the one that goes into the lunchbox component. you can get rid of everything to the left of that.

Permalink Reply by Brian on March 20, 2013 at 1:12pm

that's what I did but it gets pretty funky, half of the grid doesn't show...

Permalink Reply by David Stasiuk on March 20, 2013 at 2:55pm

could you repost your definition along with the referenced geometry, either as a rhino file or internalized?

Permalink Reply by Brian on March 20, 2013 at 3:07pm

I have your scripts included in my file for you

Attachments:

Design exploration1.gh, 37 KB
design exploration1.3dm, 111 KB

Permalink Reply by David Stasiuk on March 20, 2013 at 3:35pm

Okay, so really it's pretty easy...you literally just take your lofted surfaces and feed them into the diagrid component, and it should be good. One thing worth noting is that the way that weaverbird creates the mesh from lines doesn't always result in the mesh being oriented with its normals in the same direction. Even your two surfaces create one "pointed" in, and one out...so you can see that the mesh flip isn't necessary for the first, but is for the second one. If you do this with other surfaces and they don't seem correctly oriented, that's the place to look. Also, in order to make sure that the diagrid "closes" on itself at the surface end seam, you just need to make sure that there is an even number of columns.

Attachments:

Designexploration1a.gh, 19 KB

Permalink Reply by Brian on March 20, 2013 at 4:40pm

that's it. Thanks, I'm in my 4th of 5 years at arch school so excuse the lack of my proficiency. I've never used weaverbird before so I'll have to watch some tutorials. Thanks everyone for your assistance.