Sweeping Structure

Hi,

Some of you are aware (or use) the structural plug-ins that I'm working on.
I've just uploaded new versions that enable "paramatric" modelling of skeletal structural members (such as steel UB, CHS, RHS profiles) to centreline curves in your Rhino document. I've started a blog entry on this at http://geometrygym.blogspot.com that contains a you-tube clip demonstration. After an initial introduction, a "mini-gherkin" diagrid structure is generated in Grasshopper in the way of centrelines. After baking the centrelines, I can then apply the cross section data for a 3d model.

There's plenty of improvements to make. Soon you'll be able to tag your centrelines in Grasshopper and then my plug-in would apply the cross section data as soon as the curves were baked. Orientation of the elements still needs to be addressed (at present there is a default orientation) and I'll add an event watcher to respond when the centreline curve is modified.

I'm posting here because I think this plug-in could be very useful to many grasshopper users. You can download the grass hopper definition from the blog, and the plug-in from the wiki. The plug-ins are free whilst in beta testing, however you do need to request a license file to unlock full functionality, but please try it out if it sounds intersesting and I'll happily respond to any suggestions/ideas that you might wish to raise.

Attachments:

090729 generating structure.jpg, 313 KB

Replies to This Discussion

Permalink Reply by Liberty Moonbeam on January 9, 2010 at 9:02am

Hi Jon,
since I was away, its been a while that i contacted you because of the structural-drawing plug ins.. Thanks again for you help with it! Luckily i ve got my computer back working and the structural-drawing tools appear in the rhino tools, but unfortunately I cant apply the random voronoi pattern. it keeps telling me that the object is too large no matter which object i chose... could that be because i dont have a license yet?

Cheers
Julia

Permalink Reply by Jon Mirtschin on January 9, 2010 at 10:25pm

Hi Julia,

The random voronoi command doesn't need the license file (are you having trouble generating the license request email? the contents of the text file are copied to the clipboard in the newer versions so you can paste it into an email).

Can you email me a rhino model containing only a surface that doesn't work so I can test it? I can't immediately identify which area of the code would report that error. Did you check the size option for the command? The number of points generated will be the surface area divided by the size.

Cheers,

Jon

Permalink Reply by Liberty Moonbeam on January 18, 2010 at 9:25am

Hi Jon,

Thanx for your reply!
I think I found out what the problem is: my surfaces arent actually planar surfaces.. Is there any way to use the random voronoi on non-planar srfcs?

Cheers
Julia

Permalink Reply by Jon Mirtschin on January 25, 2010 at 2:14am

Hi Julia,

It's possible I could make some modifications for some surfaces that are "nearly" planar.
Is it possible to email me a sample surface you're trying to use this on so I can test it?

Cheers,

Jon

Permalink Reply by Liberty Moonbeam on February 7, 2010 at 12:56pm

Hi Jon,

sorry it took me so long to reply..
here are the surfaces in the rhino file.
i also have another question: when i export the rhino surfaces into cinema 4d, there are some subdividing lines on them. you cant see them when the srfs are rendered only in some view modes, they are visible in the pic. i dont mind the lines, just interested how they are created, since i might work with them in an atom array in cinema4d...
i would be thankful for a quick reply (even tho it took me so long ; ), since my deadline is in one week..

cheers
Julia

Attachments:

test7.3dm, 4.9 MB
test.jpg, 37 KB

Permalink Reply by Jon Mirtschin on February 7, 2010 at 10:39pm

Hi Julia,

I think the surface lines you are talking about must be isocurves, which are used akin to Contours to help graphically show curvature on surfaces (not so relevant for planar surfaces). They can be extracted in Rhino (and there is a thread on this I saw in the Grasshopper forum). You can also get seams on surfaces, where the "edges" of a surface are joined (ie you try to create a sphere from a flat sheet of paper where the edges touch each other).

Now, the trouble with my current algorithm is that the straight lines generated for my voronoi diagram would lift off the surface at the folds.

Is a random Voronoi important? Using the existing plug-in tools, you could do the same procedure with your poly surface that they used for the Beijing WaterCube : http://geometrygym.blogspot.com/2009/08/structdrawrhino-takes-on-wa...

Note that in the latest release of the plug-in, there are various other polygon packing routines that will give different shapes. You will have to remove duplicate intersection curves fro the time being using the Rhino command SelDup.

http://geometrygym.blogspot.com/2009/12/weire-phelan-intersecting-s... is another blog post demonstrating the tool. If this won't achieve what you're after, let me know and we'll explore some other ideas.

Cheers,

Jon

Permalink Reply by Matt on February 8, 2010 at 9:02am

I'm very interested in using this plug-in. I'm unable to locate it on the wiki. Would you please post a link?

Cheers

Permalink Reply by Jon Mirtschin on February 8, 2010 at 9:12am

Hi Matthew,

Sorry if it's not clear, go to http://www.geometrygym.com/downloads and download the StructDrawRhino plug-in. You'll need the trial license (which is free) to activate the commands you're interested in, when you run the installer, you should see a new toolbar when you start Rhino. Click on the poly packing button and follow the prompts.

Cheers,

Jon

Permalink Reply by Matt on February 8, 2010 at 9:35am

Thanks Jon,
I downloaded the tools and they are visible in rhino (v4 sr7). I'm unable to acquire a trial license and a xml file is not being created to email to identify my computer.

Cheers,
Matt

Permalink Reply by Jon Mirtschin on February 8, 2010 at 2:08pm

Hi Matt,

If you run the license request command, the text generated for the license file is also copied to the clipboard, so if you paste that into an email to me (jonm@geometrygym.com) I will return the email with instructions. If you don't get data being copied to the clipboard (this is very unusual), then email me and I'll let you know what info I need to license it.

Cheers,

Jon