Truss tesselation (on NURBS) issue

Greetings to all of you

I'm new to this Forum (although quite old in programming - lately with Generative Components, you know the weird thing geared with Microstation).

I was looking into the truss tessellation on NURBS script kindly provided by Charles Vincent some time ago.

The Rhino example attached is part of a WIP Airport terminal project - OK it's rather a test since...there's absolutely no real-life reason to do a custom MERO truss (a zillion node drilling axes combos and/or member lengths etc etc) for this type of topology (I'll transfer the envelope/definitions to Siemens NX 7.5 in order to design the load bearing structure - in this type of thing assembly/component support is critical).

Back to the truss script: It works....but sometimes - depending on the lofted topology - it doesn't (see Saved Views inside the slightly modified original script). In this particular example the upper truss grid formation is incomplete.

on the other hand the lower grid appears to be OK

On the other hand in quite a few other test cases the script works OK

That said this case is a good opportunity to discuss (if anyone is interested) of some practical ways to vastly improve Grasshopper GUI - visual editors are not a bad thing (in theory) .... but creating nested real-life assemblies is another animal - not to mention handling/managing/imporoving scripts of a certain complexity (and/or "debugging" them as is the case here).

PS: what means the assembly comment? Imagine doing this truss in real-life : let's focus to the nodes: assume that are made by a MERO style system: this means (in a CAD environment) that the node is a void assembly containing the ball itself plus shared instances of the tube member "adapters" which are ...er....hmm...assemblies containing the fixing bolts and the adapter itself .... etc etc etc.

That type of stuff.

All the best, Peter

Attachments:

TESSELLATED-TRUSS-ON-NURBS-58.3dm, 136 KB
TESSELLATED-TRUSS-ON-NURBS.ghx, 3.6 MB

Replies to This Discussion

Permalink Reply by peter fotiadis on November 17, 2011 at 6:39am

PS: this is maybe a good test for the truss script (but I have ported all the data from Microstation to NX and going back is not so easy - actually is impossible).

Permalink Reply by peter fotiadis on November 17, 2011 at 8:25am

Hmmm...just tested the opera envelope thing VS the script and guess what? the same sort of MIA truss lines appears

Of course the loft tool doesn't apply here (required: sweep 2). But the bad news are that the sweep tool appears not working - wonder why.

Anyway...CAD is a mysterious thing, he he.

In any case > get the opera envelope definition and give it a spin (replace Loft with Sweep2). See Layers inside file as well.

Attachments:

204_opera_envelope34A.3dm, 429 KB

Permalink Reply by peter fotiadis on November 18, 2011 at 10:08am

Here's a more realistic "puzzle" with regard an imaginary (BTW: avoid this in real-life) MERO type solution for NURBS trusses. Classic solution there (U150 support plus Corrugated panels plus Foamglas plus serrated plate fasteners plus Zink coating). Obviously the hot spot here is clash detection (see some conical members that touch each other). Add the required FE Analysis for defining member topology...and the "simple" task becomes a rather challenging one. Notice the variable "adapter" for mounting the panel support system

You would probably agree that porting this kind of "detail" into Grasshopper ...er...requires some better ways to manage complex situations. See Generative Components on that matter (and the script "rows" that can emulate - so to speak - some kind of flow)

Attachments: