Geodesic Domes

Replies to This Discussion

Permalink Reply by peter fotiadis on December 10, 2011 at 3:42am

OK, that's the mother of all threads.

Only tensile non elastic membranes is a more neat engineering solution (the best academic thing on that matter is FormFinder the best real-life app is Birdair propriety software). Think Kangaroo with RON 100 fuel (add some nitrous oxide).

Back to domes. 

1. Obviously you know the free WinDome Bono thing...but anyway get it (code included).

2. As I said on another thread (http://www.grasshopper3d.com/forum/topics/the-necessity-for-a-data-...)  ... the big thing in AEC (because, for instance, nobody does domes for decoration/artistic stuff etc etc) is how to implement already designed things (see images above) within  a smart stuff definition (or many).

3. Goes several steps beyond: these "breps" (to speak GH/Rhino language) are in most cases nested and some parts are "locked" for transformations some other not. That's the big thing when trying to outline real-life AEC solutions in the so called Smart applications. I think that this is not doable in Rhino since there's no way to edit (in place) a nested block.

4. Goes even further: for each custom made thing (truss nodes and the likes) ... there's a bill waiting. Meaning that the less customized a solution is (with regard industrial sourced existed parts) the more is possible for the client to sign the dotted line. 

Best, Peter

Attachments:

• windome48.zip, 268 KB

Permalink Reply by peter fotiadis on December 10, 2011 at 6:36am

OK, here's the 1M idea :

Imagining making a wire dome (like the one supplied by your tools). That's a "static" collection of geometry (not a big problem, mind).

Say like this ugly thing (WIP planetarium in Microstation):

But let's stay in Rhino for the shake of the thread...:

..the tricky bit is to use in GH a set of "static" geometry and instead of exploiting (at infinitum) forms, shapes, and such ...just finish the difficult part of the story:

1. Assume that this is covered the classic way: corrugated sheets + Foamglas T4 + fasteners directly glued on Foamglas (avoid classic fastener penetration = leaks) + aluminum guides + some MV Zink sheets (or CalZip or copper or titanium).

http://www.foamglas.ae/building/en/downloads/

2. The catch in such type of roofing is to make a "smart" definition (GH or Gen Comp) that can deploy these sheets into the existing geometry taking into account (a) their maximum flex/bending capability - trying to create a "skin sphere" instead of a faceted ugly chaos (b) their physical size in order to avoid getting into the usual wedge situations (i.e: examine if a given flexible sheet of metal - kind of ribbon- can cover a NURBS of some sort). 

In other words and in the broad sense of things: how we can inquire static geometry in GH and get back, say for a start, a collection of working planes in order...etc etc etc. Or how we can use Orient brep type of components in Rhino geometry?

Permalink Reply by robert cervellione on December 10, 2011 at 10:36am

i think this is a really interesting problem and one that has been worked on many times.

2. The catch in such type of roofing is to make a "smart" definition (GH or Gen Comp) that can deploy these sheets into the existing geometry taking into account (a) their maximum flex/bending capability - trying to create a "skin sphere" instead of a faceted ugly chaos (b) their physical size in order to avoid getting into the usual wedge situations (i.e: examine if a given flexible sheet of metal - kind of ribbon- can cover a NURBS of some sort). 

first it is very easy to 'work with' existing geometry in GH and use that as a starting point. but the interesting part is the skin panels. you talk about two things, not having it faceted so i assume you want double curved panels? and then you want to optimize the panels based on the curvature and max sheet size. because you are using a geodesic dome then the curvature is constant  which makes things a bit easier.

so the biggest issue is how to take the triangular piece of sphere that connect back to the super structure of the dome (that you show in your image) and sub divide that to the proper size panels that are able to be fabricated. you also want to minimize the amount of unique pieces that are created to make it more economical (the fact that it is a sphere will also make this easier).  

because it is a sphere and the structure is comprised of identical triangles each piece of triangle sphere will be identical, the only only thing is how many different panels pieces will be needed to make up each section. 

i think this can all be accomplished fairly easy in GH (or GC) using built in function to sub divide the panels, add size constraints and optimize for uniqueness. its a fun problem that should not take to long to figure out. 

Permalink Reply by peter fotiadis on December 10, 2011 at 11:58am

Hi Robert

Well..the big thing is not to work with existed geometry but with an assembly type of geometry (made elsewhere) that has constrained and not members.

I'll be back to further explain in depth what I have in mind

Take this naif dome and think > assuming that is "solved" (at least with regard the dome members) ... by what means can I talk back to Microstation (actually Siemens NX) sending (exporting) spheres that are Shared Instances, members that have Shared Instances (the cones) and members that are allowed being transformed (tubes).

With regard the skin thing...more soon

Best, Peter

Attachments:

• 111210dome2.gh, 16 KB

Permalink Reply by peter fotiadis on December 10, 2011 at 12:13pm

Oops forgot to flatten the grafted thing

PS: with all Circle(s) Preview off why the %#%# things still are on display?I'll be back with some real-life stuff applied to that dome (like this one):

Permalink Reply by robert cervellione on December 10, 2011 at 1:29pm

i just have to mention that you look to be very adept at microstation, why not just do this in GC. it will let you directly use all of your microstation information, no translation needed. 

Permalink Reply by peter fotiadis on December 10, 2011 at 2:59pm

Er...don't tell to anyone but whilst MS behaves OK (up to 8.11.09.237 build, the very latest that is) GC (the standalone) is so slow ... zzzzzzzzzzzzz... can I have another triple espresso  please ...not to mention that Robert Aish escaped to AutoSomething ...meaning that no captain left on board.

Also don't tell to anyone but MS is not exactly cutting edge with regard proper assembly/component management capabilities (a what?) not to mention that I hate Levels -  more than my sins (a lot).

And what about that DX ? Can you imagine a proper CAD fanatic to do things with game cards?

That's the reason that I'm playing with the GH idea - but doing tricks in Canvas is not the same thing as designing real-life AEC stuff.

But as Jon says: the "one application of all things" is pure Utopia.

But against all this and that...I love Microstation, he he.

Permalink Reply by Jon Mirtschin on December 10, 2011 at 12:53pm

Nice model.

The question about exporting/exchanging this information with intelligence, attributes and relationships (not just sending the geometry) to software such as Microstation and Siemens NX is a topic I have a lot of interest in.  Modelling again "from scratch" seems like such a waste of time and effort that could be better spent if it can be generated and derived in the Grasshopper model.

Permalink Reply by Jon Mirtschin on December 10, 2011 at 12:22pm

A sphere should be easy enough, a geodesic dome has uniform lengths and faces (to some tolerance) although this tolerance seems to be a little more significant the "higher" the frequency.  

I was involved in a (seemingly) relevant roof design project earlier this year, we had a desired free form shape (but not a constrained surface that we couldn't deviate from), we wanted as many equilateral triangle glass panels as possible (easy to install without regards to orientation) with a dominant size and minimal variations.  I used a dynamic relaxation routine (a variation of the mesh relaxation tool in StructDrawRhino) with the ability to draw in additional faces from the perimeter (so I didn't have to predetermine the number and topology of faces).  This took advantage of the "tolerance" gap between faces, as the pure "geometrical" form comprising "coincident" edges is constrained in the forms it can emulate.  (There's more images of this in my gallery).

We hope this gets built next year.  I haven't really got the tool "user friendly" enough to the point of making it a part of the StructDrawRhino toolkit (there was a little manually operated smoothing where some of the nodes "crinkled" to achieve equal edge lengths) but I can demonstrate it on projects upon request.  Of course if the glass "grid" is targeted, the underlying (but offset) steel grid then comprises steel members of varying lengths and connection details with minimal repetition.  With direct "BIM" exchange to software such as Tekla (and then NC fabrication) this is less of an issue (but indicative that it's not as simple a matter of optimizing for one objective).

Permalink Reply by Jon Mirtschin on December 10, 2011 at 12:46pm

By the way, I know this is a thread primarily on domes and geodesics, but have you seen the blog post on non linear form finding from Grasshopper (using the Oasys GSA relax solver in this case, but others have done some similar solving using Sofistik and no reason it can't be exchanged to other solvers.  Refer http://geometrygym.blogspot.com/2011/06/grasshopper-gsa-form-findin... as a starting point.

Let me know (I will take a closer look when I find a moment) what features are in windome you would like me to enable.  I haven't done elliptical or parabolic domes but most of the options look similar.

Permalink Reply by peter fotiadis on December 10, 2011 at 3:14pm

I'll dig into that form finding thing...since (and excluding the propriety Birdair software) all the apps around are a bit..er...out of question to be honest. What is actually needed is the interactive FormFinder capabilities ... but geared in a serious smart CAD app (Bentley should acquire that company years ago).

http://www.formfinder.at

Worth mentioning that personally I rate membranes as THE neatest engineering approach known to mankind, like driving a Ferrari Italia VS any other sports car.

Back to domes: Indeed elliptical and parabolic domes are far more interesting and if possible you should drop some lines of code more - after all this is the era of liquid Architecture (but I have no idea if this is the next big thing - obviously sliced bread still is the Numero Uno).

best, Peter

Permalink Reply by peter fotiadis on December 12, 2011 at 3:21pm

in the mean time, I've spend 1 hour more on that dome of yours:

1. Project curve to surface is odd > doesn't accept direction (in the literal sense of the word) and as a result the triangles are projected twice to that sphere ({a;b;c;d;e;f}(i) > (e;i} required in order ... etc etc etc).

2. I'll design some real-life stuff (assembly/component mentality) for supporting the skin as a challenge for what is required when inserting "real objects"  in GH:

Attachments:

• 111210dome3.gh, 48 KB