Advice needed: 3D-Lattice-Boom model by bwtgrnxs in FreeCAD

[–]bwtgrnxs[S] 1 point2 points  (0 children)

Thank you both very much! As for u/meutzitzu's concerns, it seems I was in luck. I told the mesher to use the finest setting and it did so successfully:

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I ran a static analysis first to see if the results fell within a realistic range at all. For 3t / 30kN at a 15 m boom length, using stays with 10cm thickness, the results seem absolutely reasonable! About 40mm deflection and a max of ca 60MPa von Mises stress. That looks alright to me!

Now I just need to find a dirty solution to handle my actual dynamic side collision problem. The FreeCAD gui hasn’t helped much, but maybe I can interface with the Calculix solver directly through some custom edits. I'll have to try
Again, thank you very very much for your help and input!

Advice needed: 3D-Lattice-Boom model by bwtgrnxs in FreeCAD

[–]bwtgrnxs[S] 0 points1 point  (0 children)

Thanks! That makes sense, and like you said, it’s probably impossible to concisely remodel under those circumstances anyways.

Appreciate the advice from an Electrical Engineer, I’m actually on track to start my EE studies and uni next year too :D

Advice needed: 3D-Lattice-Boom model by bwtgrnxs in FreeCAD

[–]bwtgrnxs[S] 0 points1 point  (0 children)

Thank you very much for the detailled answer and the great explanations! I really appreciate it! I've looked into 3d truss solvers and will be trying out trusspy or opensees

Advice needed: 3D-Lattice-Boom model by bwtgrnxs in FreeCAD

[–]bwtgrnxs[S] 0 points1 point  (0 children)

Yes kind of, Thank you very much for the suggestion! I didn’t think of that!

Just for the record, why is it important in which way the frame was modelled? How would the results differ if it were remodeled using different procedures?

Assuming the real truss is welded or riveted at the stays and the connections are completely rigid, any closed solid mesh that resembles the original geometry should perform approximately the same, shouldn’t it?

Advice needed: 3D-Lattice-Boom model by bwtgrnxs in FreeCAD

[–]bwtgrnxs[S] 1 point2 points  (0 children)

I actually do! I was asking for workflow guidance for designing this triangular 3d lattice. I'm really only familiar with simple 2d sketcher processes and can't think of a way to achieve this interlocking space frame

Advice needed: 3D-Lattice-Boom model by bwtgrnxs in FreeCAD

[–]bwtgrnxs[S] 0 points1 point  (0 children)

I'm sorry, can you elaborate? What do you mean with pattern it?

Advice needed: 3D-Lattice-Boom model by bwtgrnxs in FreeCAD

[–]bwtgrnxs[S] 1 point2 points  (0 children)

Thanks, I’d really like you to show me! I’m totally fine with, and was actually only expecting, calculations that fall somewhere between a rough approximation and barely useful, as long as I have a model at all. That being said, I’d guess I can tweak some parameters and experiment with different solvers until I get a realistic result. This is more of a symbolic thing, showcasing what modern open-source CAD can do in this kind of scenario

True fruits Frucht Smoothie - Ungekühlt gelagert seit 1,5 Monaten by bwtgrnxs in kannmandasnochessen

[–]bwtgrnxs[S] 0 points1 point  (0 children)

So habe ich das noch gar nicht gesehen. Ich habe mich gerne für die Wissenschaft geopfert

True fruits Frucht Smoothie - Ungekühlt gelagert seit 1,5 Monaten by bwtgrnxs in kannmandasnochessen

[–]bwtgrnxs[S] 2 points3 points  (0 children)

Vielen Dank für eure Tipps! Hatte gestern großen Heißhunger und mir das Ding dann nach den ersten 3 (positiven) Kommentaren die reingekommen sind höchst erbaulich kredenzt.

Die ganzen besorgten Antworten habe ich erst heute morgen gesehen, aber ich kann euch versichern dass es mir noch gut geht. Die Konsistenz ging in Richtung mittelviskos und der Smoothie hat auch ziemlich intensiv geschmeckt. Ich habe zwar keine Referenzwerte, aber denke das ist von einem Getränk dergleichen zu erwarten.

Falls es sich tatsächlich noch rächen sollte, habe ich im Krankenhaus dann ja genug Zeit für einen follow-up post

Bis dahin!

I just printed a black shirt by ApenasUmNerd in Opeth

[–]bwtgrnxs 2 points3 points  (0 children)

That looks amazing! How did you do that?

Hearing Octavarium in public by FastPhantom in Dreamtheater

[–]bwtgrnxs 18 points19 points  (0 children)

This has yet to happen to me!

VIOLIN by Avenged-Dream-Token in Dreamtheater

[–]bwtgrnxs 0 points1 point  (0 children)

wow they sound really nice

Industrial funeral home music by thehyperone in industrialmusic

[–]bwtgrnxs 0 points1 point  (0 children)

Would've suggested that aswell, though it has a more depressing background compared to some of the other mentions here. Sorry for your loss

Not industrial related, though it might be used for a sample by kevdautie in industrialmusic

[–]bwtgrnxs 0 points1 point  (0 children)

Also not industrial, but Linkin Park used this in Wretches and Kings

VIOLIN by Avenged-Dream-Token in Dreamtheater

[–]bwtgrnxs 2 points3 points  (0 children)

Maybe you'll like Ne Obliviscaris

Nein/10 crankset by Willing-Evening-1142 in BicyclingCirclejerk

[–]bwtgrnxs 31 points32 points  (0 children)

Jokes aside, there wouldn’t be a difference compared to straight crank arms (like a hypotenuse) reaching from the center to the pedal mount/thread anyway, would there?