triangular mesh frame optimization

Hello. I'm an architecture student with little experience who just graduated from school. But I decided to give a shot at a small scale real life competition. I intend to use triangular mesh frame to support the windows and the whole building. The best example to illustrate this is the Blob in Eindhoven (see attached image), although I don't intend to use a blobby form.

But the main question here is the optimization of the structural mesh frame. It is easy to make a mesh in rhino for any given surface by simply typing "mesh", but first the individual shape and size of each mesh face will vary, and second the connection vertex between different faces are all different too. As a result, it will be incredibly hard and costly to build in real life.

So, as many others have already did in this forum, I'm wondering ways of optimizing mesh by limiting the shape and size of each face. And also can someone shed me some light on how does real life "meshing" work (examples of connections and construction methods)?

From searching this forum, I found lots of similar threads. Many of them ask how to cover a curvy surface using identical equilateral triangles. The answer seems that a smooth covering is impossible as long as the surface isn't developpable, and only approximations can be made using kangaroo.

Daniel had some good scripts regarding this http://www.grasshopper3d.com/forum/topics/triangulation-scrip-with and

http://www.grasshopper3d.com/forum/topics/folded-plane-subdivided-i...

And I also encountered a script that can approximate a curved surface with limited set of triangles, but cannot find it anymore.

But all of the scripts above have their problems in real-life fabrication, as the first script has triangles approximately equilateral but not really so, and the second script has to change the border of the surface. I'm just wondering how did people do this kind of thing in real life, like the Blob in Eindhoven or Ghery's abu dhabi guggenheim museum's long transparent tubes. Did they just simply prefabricated everything or did they have everything optimized to the max? How did they do that?

Sorry for this long and demanding question lol. But any direction of research is appreciated. :) Thanks!

Attachments:

blob eindhoven.jpg, 124 KB
abu dhabi guggemheim ghery.JPG, 127 KB

Replies to This Discussion

Permalink Reply by Jonah Hawk on March 6, 2015 at 4:47pm

There are only three volumetric forms that have identical equilateral triangles. Ask Plato.

The fact is that every triangulated surface you see in architecture has at least two different sized triangles. Geodesic domes are the simplest example of this. Most of the large geodesic domes you see have six different edge lengths. This is for a sphere, where the curvature is uniform across the surface. When you introduce compound curved surfaces, the number of unique components goes up.

You can use Kangaroo and other tools to try and optimize a triangulated mesh over a surface. There are various grasshopper definitions out there that will continually iterate over the mesh, moving vertices until all edge lengths are as close as possible. But this does not guarantee that the triangle panels will have the same angles/form.

often the panels are not exactly the same size but they are close. So the panels are manufactured the same size and shape but the difference is made up in the glazing, frame or mounting method. The gaps vary but the panels are identical.

You could build a definition to sort and group them according to their deviation from a norm. For example: Stack all the panels with the same vertex (A) at 0,0. Align a single edge, (A-B). Then measure the deviation of points B and C and measure the angles, ABC, BCA andCAB. derive some sort of tolerance that groups similar panels together.

There are examples of this out there.

Permalink Reply by shuo zhang on March 9, 2015 at 2:33pm

Hi Jonah, thank you for taking your time to answer my question! And sorry for my delayed response as I need to go to the library for internet.

Okay I didn't ask Plato and didn't know about the 3 volumes :) (except I kinda knew about the geodesic dome) I actually switched my mind in the design and decided to prefabricate every panel since I reduced the number to 20. But still I remain interested in this question, and if I don't misunderstand you are saying that most people use kangaroo to iterate triangles as equilateral as possible, and then sort and group them using a script, to finally prefabricate one model for each sorted group, and any deviation is dealt in fabrication? Sounds good to me, but if they use multiple length do they get exact panels then?

Permalink Reply by peter fotiadis on March 7, 2015 at 12:47am

Well... let's speak a bit having the big picture in mind - not just panel aesthetics.

1. I have several defs that do a variety of similar things but they are ALL in C# and thus they don't use components (other than Kangaroo - if required). Anyway notify if you want some taste of them (but they are a bit "chaotic" : too many parameters etc etc ...). Warning: Almost all are written with MCAD apps in mind: GH is used SOLELY as a graphical editor/topology solver and just makes the simplest instance definitions possible in order to send them (via STEP) to some MCAD (Frank G uses CATIA/Digital Project as you may probably know, CATIA is my favorite toy as well) for actually designing the components and composing the whole.

2. "Equality" in modules (panels/glass/lexan) it's not an issue (other than aesthetics). I mean cost wise since modules are prepared via CNC these days. I wouldn't suggest to waste your time with "equality" puzzles and completely ignoring the big picture (real-life) that is FAR and AWAY from aesthetics. I mean: assume that I of someone else or Daniel can "equalize" things (up to a point): Is this sufficient for designing a similar real-life solution? In plain English: don't get occupied by the tree and ignore the forest.

3. As regards the frame in most of cases some MERO type of modular system is used: either a "flat" dome-like arrangement or a classic spaceframe or a hybrid system [push: tubes, pull: cables]. Hybrids are the most WOW (and costly) for obvious reasons. When properly done (and combined with a planar glazing system) THIS is the star of the show.

4. As regards the skin we use either "hinged" custom stuctural/semi structural aluminum extrusions (they can adapt to different dihedrals up to a point) or classic custom planar SS16L systems that also can adapt to dihedrals. A custom planar glazing solution is hideously expensive, mind (say: 1K Euros per m2).

5. Smart Glass tech (changes light transmission properties under the application of voltage) is gradually penetrating the market especially in future bespoke designs.

So in a nutshell: these are "pro" territory - if I may use the term, thus I don't expect to find ANY similar "turn-key" solution in the very same sense that you can't find a tensile membrane turn-key solution.

Meaning that practices that can do it ... er ... they keep the cookies for themselves.

Permalink Reply by shuo zhang on March 9, 2015 at 3:10pm

Hi Peter! Thank you for taking your time to answer my question and sorry for my delayed response as I need the library for internet.

Wow that's a lot of information!

1. I'm a total noob at programming but Yes I would like one or two scripts so that I can have a taste of what it is in the real business. I'm trying to learn programming though and I hope my dad (who is a programmer) can help me.

2-4. So equality isn't an issue then? I already changed my mind about the project and decided to prefabricate them since I reduced the number to 20. But then you mentioned about custom planar glazing being hideously expensive. What does it mean? is it like the attached picture? And can a MERO system only be used in a standard organization (such as a space truss) or can it be used to adapt to unpredictable double curve surfaces?

5. I don't plan to use smart glass as my project is small and isolated and I don't think it can be electrical. But thanks for the info.

Anyway I'll do more research about some of the stuff you mentioned especially the frame and the skin part (I always assumed they were the same thing in structure, or were they?) Also are you an architect or a structural engineer? Do architects get this kind of knowledge too? Thank you so much!

Attachments:

custom glazing.jpg, 152 KB

Permalink Reply by peter fotiadis on March 9, 2015 at 3:52pm

Hmm + Hmm

1. King of glazing systems i.e. Planar glazing is a frame less glazing system that accepts glass panels (up to 45mm) and supports them via static or adjustable "brackets" :

2. Pilkington (http://www.pilkington.com/) dominates the planar market. Charges "around" 1K Euros per m2 for a "plain" system. Personally in bespoke projects I design my own stuff but due to economies of scale ... they cost a bit more (but they look far more sexier, he he) . On the other hand only in a bespoke project I could dare to suggest such a solution (for a large scale building we are talking lots and lots of dollars).

3. Several scales below (aesthetics) you can find static alu systems (either structural or semi-structural):

Or hinged systems (either structural or semi-structural) capable to adapt in contemporary double curvature facades/roofs/envelopes/cats/dogs etc etc ... pioneered worldwide many years ago by my best friend Stefanos Tampakakis (everybody in UAE knows that genius man: http://www.alustet.gr/company.html):

4. With the exception of some paranoid things that Guru Stefanos does for Zaha these days we are talking about planar "facets" (obviously a triangle is such a planar facet). The current trend is: the more edges the better (humans excel in vanity matters). But achieving planarity in, say, quads (like yours) it adds another "restriction" on what you are doing. Until recently Evolute Tools Pro was the only answer. But right now ... well let's say that in short time you'll be greatly surprised by some WOW things in this Noble Forum, he he.

5. MERO (and obviously custom systems) can adapt (at almost no extra charge) in anything imaginable. But in a bespoke building ... well.. you know ultra rich people: they don't want MERO anymore since "everybody" does MERO solutions. Vanity, what else?

6. Smart Glass would become a must in the years to come: Eco-Architecture MUST dominate everything you do. On the other hand spending millions to do some extra WOW stuff (Vanity) ... it doesn't look to me very Eco-Friendly/Whatever ... but let's pretend so, he he.

7. I'm Architect but a bit different from the norm: for instance I smoke cigars (highly politically incorrect stuff) I always talk openly (ditto) and I ride lethal bikes (ditto).

may the Force (as always the Dark Option) be with you: go out there and kill them all.

best, Peter

Permalink Reply by taz on March 9, 2015 at 7:22pm

You neglected the Waagner Biro, Seele and Novum category of structural freeform glazed systems. The OP's Eindhoven project reference project was built by Waagner Biro.

http://www.waagner-biro.com/en/divisions/steel-glass-structures/ref...

http://seele.com/structure-en-2.html

http://www.novumstructures.com/novum/index.html

Permalink Reply by peter fotiadis on March 10, 2015 at 1:25am

Actually no ... any modular freeform system is composed:

1. LBS (Load bearing structure):

(a) via a "dome" like "flat" structure - steel/wood/carbon/aluminum (custom or MERO type)

(b) via spaceframe [with "thickness"] structure - steel/wood/carbon/aluminum (custom or MERO type, with or without cables)

2. Skin:

(a) planar glazing (glass/polycarbonate) or planar opaque insulated composite panels (zink,aluminum,SS, titanium).

(b) "hinged" aluminum frames.

But my personal opinion is that - all things considered - a tensile membrane with insulated material (TensoTherm and the likes) is much more economical, handsome, simple and purposeful. The greatest ever stated it clearly: Less Is More, not to mention that other thingy: Form Follows Function.

On the other hand , truth is that all the modular structures are really stunning and utterly challenging to design and fabricate ... but it's hard to justify the cost VS benefits.

On the other hand ... well ... people are always eager to exploit "new frontiers" at any cost and without thinking too much the big picture: explain the reason to use a structural glazing system where the guarantee for the (structural) silicone it doesn't exceed 15 years. Is such a big deal to use a semi-structural solution?

Permalink Reply by shuo zhang on March 10, 2015 at 2:23pm

Hi Taz, thanks for the info! Their projects look so coool.

Permalink Reply by shuo zhang on March 10, 2015 at 2:22pm

Hi Peter, I forgot the name of the dark side of jedis, but i must end up being one of them if i live in star wars lol. Thank you for this extensive explanation on the topic. but my brain is getting fucked up by all this bombardment. That project isn't mine, i found it on internet. Actually all I want to know is how to build this thing (see attached picture), yeah that's my project and I just wanna make it structurally sound but have no clue. Any suggestions? You can just point me some direction as i feel bad making u write an essay. lol.

Attachments:

test render 21.jpg, 43 KB
test render 23.jpg, 38 KB

Permalink Reply by peter fotiadis on March 10, 2015 at 3:56pm

That's a small thingy with no insulation requirements. Thus ... the simplest way (LBS) is ... er ... to forget the ultra WOW/complex/dizzy/Oh my God things and use welded (probably on site) tubes (steel/aluminum or SS if you are rich). For aluminum and on-site welding you'll need Argon. OK welding destroys galvanic protection ... but who's counting? (besides nothing lasts for ever, he he).

The skin ... well there's no water tightness requirements thus weld (or spot) linear, say, 5/30mm steel "Bright Flats" either across the "top" of a given tube or both sides.

http://steelandtube.co.nz/product/ste/engineering-steels/bright-bar...

http://www.gspsteelprofiles.com/catalogPages/coldDrawingSteel.php?C...

These 5/30 linear things make us the "niche" (per panel) for the transparent/opaque stuff: Avoid glass in this occasion: use 5/6/8 mm massif polycarbonate that is flexible and can tolerate non planarity rather well (more than probable if the welding is done on site). Keep in mind the sheet size (see link) in order to avoid waste material. Use some fancy Allen/Torx screws visible from behind (WOW) and that's all: case closed.

http://www.plastix.com.au/images/polycarbonate.pdf

http://www.plastics.bayer.com/en/Products/Makrolon.aspx

http://www.glazinginnovations.co.uk/technical-structural-glazing.php

http://www.palram.com/Architecture

http://www.trespa.com/

best, Peter

Permalink Reply by shuo zhang on March 10, 2015 at 4:25pm

Hi Peter. Thank you so much for all these resources! I think I can finish my project without it being completely ridiculous now. Honestly I'm not trying to win at all (after only 3 years of arch education) but to have a good learning experience. I learned a lot from you.

best, Shuo

Permalink Reply by peter fotiadis on March 11, 2015 at 1:05am

Allow me a couple of minutes to do something to start with