Equal distance between points+finding support using Galapagos

Need help! I'm trying to generate an abstract structure from wooden beams, using kangaroo and karamba to test its sustainability. The project needs to be done really fast, so I'm looking fo some simple solutions. The general view is something like that

I haven't found the solutions for the following questions(in my head):

1) is there any way to generate the model from beams with defined length, for example if I want to make the entire structure from 6m-long timbers. I mean how could I achieve equal spaces between random points?

2) I like the idea of finding the location of possible supports using Galapagos to minimize the displacement of the structure, but I can't understand the principles of generating those indicies.

Could somebody possibly explain me something? Thank you!

Replies to This Discussion

Permalink Reply by peter fotiadis on December 11, 2015 at 3:28am

Here's an indicative sketch using tensioners and adapters. It's not the simple stuff that you have in mind ... but we want some artistic event not Armageddon.

In fact without realizing it you are after a Tensegrity system ... but that's out of question for a DIY thing > forget it.

Note: clash situations on that type of "trusses" TOPS the list of things that MUST been addressed prior ANY other (via trigonometry and .. hmm ... code).

Still this can't address the floors "little thing" ... therefor the safest way to do that type of stuff is the MERO way (after all these famous Germans know a thing or two about real-life "practical matters", he he).

Another safe way to rigidly connect wood (or other) beams at variable angles ... but requires cash + cash + ... + cash > forget it.

Attachments:

RUSSIA_RINGS_V1.3dm, 2.1 MB

Permalink Reply by Maria Ostroumova on December 11, 2015 at 5:32am

And one thing more - I think we should have the more or less exact model of this structure, I mean we can't make it "on site", the theatre must approve the general idea in terms of location of people on stage(musicians) and supports(because we have exact size of the trusses above). We also must think about the audience and visibility. Armageddon is absolutely not what we are planning...

If I choose the first sceme of connection, how would you recommend to calculate the system?

Permalink Reply by Maria Ostroumova on December 11, 2015 at 6:19am

I had another idea to divide all the construction into blocks (to simplify the inslallation) and use welding to connect beams in place...

Permalink Reply by Maria Ostroumova on December 11, 2015 at 4:38am

Thank you so much,Peter!

I agree with you about wood and stuff but there is some feature of a project: aluminium can create some hotspots when being highlighted by projector, that could be important for the performance (remember the 3d-mapping we want to make).

And in this case we really need rectangular sections as cylinder can cause troubles for mapping. And what is also important, we will have only 2 days for this installation, so I it is a kind of a panic-situation for me) It will be really nice if you could possibly suggest some solutions for connections!

And answering your question - the concert will be only one day, it is the last day of this theatre in Saint-Petersburg before its total reconstruction. The last leaf of the season) But me and my friend we are thinking about some kind of huge art-project next year!

Permalink Reply by peter fotiadis on December 11, 2015 at 7:49am

huge art-project eh? Skype before that, he he (Armageddon and the likes).

Back to topic:

1. Aluminum when properly coated can absorb even a black hole (for instance using dedicated stuff from Libert or Tikkurila or ICI etc etc). In any case ... you MUST treat the nodes that way if wood etc etc. BTW: Rectangular ALU members are (obviously) 2 in a penny in the market ...but ...

2 ... but let's do the cruel thing: Kill and enjoy: this could yield considerably bigger members (like Godzilla: the bigger the better) and seriously degrade the airiness of the whole idea (to the extend ... er .. hmm).

3. Now comes the pain: is this thing scheduled to support some "floors" for the performers? If yes ... then ... er ... what about forgetting completely rings of fire or Norseman or Captain Hook stuff and doing some multi adjustable RIGID nodes ? - in order to avoid some embarassing moments, that is (I'll post soon a "simple" solution as soon as I can find it [blame Alzheimer]).

4. By what means can you address the clash BIG ISSUE? (I mean: are the beams clear each other AND are the nuts and bits of any Node system capable to adapt to different angles?). But fear not: I have code that does this.

5. Welding on site (Mama - mia): you can't be serious eh? welding the nodes and then bolting the @$%$@ beams? > Armageddon ^ N - do you know a very famous bridge (Golden Gate cut and paste) in Japan that ... blah, blah.

Or you mean this type of nightmare?

more soon

Permalink Reply by Maria Ostroumova on December 11, 2015 at 8:45am

Oh no, the structure is self-bearing, those platforms for musicians are separate!

Talking about welding, i had to hear the expert opinion, otherwise they don't trust me!)) (I knew it was a really bad idea)

Permalink Reply by peter fotiadis on December 11, 2015 at 10:40am

Separate yes but imagine mixing the WOW thing with the platforms LBS > purity is lost.

Anyway get this in STEP214 format as exported from CATIA; not "very" simple nor DIY... but you can combine the components in a variety of ways:

1. For cases (like the pics that I've provided) were valence 12 is in the pipeline (all triangulated trusses have valence of 12 meaning serious clash restrictions - not even a MERO can escape from such stuff). Obviously the further from the node the beams start ... the more freedom we have (but at the cost of beefier parts: no pain no gain).

2. IF you decide to support the performer platforms via the truss.

BTW: for the structural part ... well ... you can attempt addressing it with regard the beams itself whilst for the nodes, nuts, bolts, tensioners, adjusters, cats and dogs ... cross fingers(*). But anyway and with regard the DIY easy-busy "ring" type of node have in mind that the Captain Hook way guaranties tears (and a rather unstable structure; watch for resonance effects as well IF the music is a bit loud).

(*) I mean usually we use FEA for that type of bespoke systems (something that I guess is not available - or is it?) because in most of cases trusses collapse NOT due to failure of the main members BUT because some idiot "forgot" to evaluate a humble nut or a bracket or something "minor" anyway.

Attachments:

RUSSIA_NO_ARMAGEDDON.stp, 1.8 MB

Permalink Reply by mark zirinsky on December 9, 2015 at 3:40pm

Build your structure out of equilateral triangles

Permalink Reply by Maria Ostroumova on December 9, 2015 at 3:50pm

Thank you) This was my Plan B)))

Permalink Reply by peter fotiadis on December 11, 2015 at 11:26am

I like that thread: so let's start from node 0 for Plan X (And Y).

1. What about a Tensegrity truss? Truth is that are a "bit" complex (for heavy AEC purposes) but in your case ... we are talking about an airy "floating" thingy. The randomness issue ... well .. let's say that is 10 lines of code more (and you can do it the DIY way: even with wood "tubes" and a lot of cables).

2. What about a paranoid classic tetra truss with some random stuff in the code?

BTW: the above is this

with some If this then that lines added to the C#.

Permalink Reply by peter fotiadis on December 11, 2015 at 12:44pm

And here's all what you need for a double tetra (NOTE: ONLY as a decorative object) tensegrity minimal WOW thingy.

Tension "cables" can be made from nylon (say with R ~1.5 mm) and the "reflective" Norseman can being replaced by polyacrylamide machined adapters > so the wood would be suspended from nothing > as the greatest ever stated: Less is More.

The faster you start doing it the better, he he. Compare with ANY heavy "classic" wooden beam truss with all the issues associated with this archaic approach. You don'tt even need structural analysis > what for? > just do it.

Attachments:

RUSSIA_DECORATIVE_DIY_DOUBLE_TETRA_TENSEGRITY.3dm, 2.7 MB

Permalink Reply by Maria Ostroumova on December 11, 2015 at 1:53pm

Oh my, Peter, I must have some time to analyse all this...I like your idea, as I can understand, the tensegrity structure will bear itself and will keep its space rigidity, so that we won't have to worry (I will anyway). The most mystery thing is to find all the details for connections,I will check it out. I really like the tensegrity. Yep!