Sweep along a network of curves


The goal here is to sweep the section along this network of curves.

Vertically it could be quite straightforward (well if it was that straightforward for me, I wouldn’t be writing here…). I thought I would need to align some planes with cuves and sweep from there.

Horizontally could be a little bit trickier as the section needs to follow the angle formed by the vertical curves in order to have a plane, even though curved, in between each sections.
There would be two half section with a different angle. So I should need two plans with a different angle attached to the same point.
Not sure I’m very clear but the goal is to form a sort of veranda, its structure.

HullDesign.gh (257.8 KB)
hull design.3dm (5.3 MB)

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I’d use Surface Frames instead of Mesh Surface to subdivide the surface. For the Sweeps you need to use Orient to orient the section from a reference plane to all target planes.

HullDesign.gh (275.9 KB)

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Too slow ! :crazy_face:

Not sure about the sweeps though, there is torsion along the beams, is this suitable ?

HullDesign.gh (262.2 KB)

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Looks fantastic, but only horizontal beams are supposed to be curved, the vertical should be straight.

And the tricky part is that the horizontal beams should have an angle so that they follow the angle made by the vertical beams.

The glasses will be polycarbonate and can only be curved in one way.

With your current surface, some of the panels are twisted.

Should be suitable… But you’re right, when I look at it, my brain has difficulties to see the end result : ))
Logically, if 2 opposed beams are straight, it should do it.

Anyway, the last trick is that the horizontal beams should make an angle to follow the angle formed by the vertical straight beams.
I thought I would use two half sections that would be aligned with two planes, one parallel to the lower beam, and the other parallel to the upper one.

hmm… Makes sense. Are you sure? I thought if two beams are straight, the glasses should be curved only one way so should be fine.

The panel marked with an ‘x’ is twisted no matter if some of the edges are straight.

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Do you mean this kind of section ?

You could create a polar array of one ‘arc’ and loft it with straight sections like this:

This leads to strips of identical panels.

hull.gh (30.5 KB)

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I see… Makes sense and looks more optimised.
I don’t know how to use custom preview though.

The only problem I notice now is that the horizontal beams are not parallel anymore so it causes a problem to achieve the way-out door which was situated on the upper right of the structure.

Also I’m a stubborn kind of guy and hadn’t used my 3D printers for a while so I give it a try. : ))))


The profiles aren’t trimmed yet.

Are you planning on 3D printing the entire structure?

Just the polygon you mentioned to have a try.
How do you use the custom preview on GH? I can’t see any preview, only the 2 nodes but I don’t know what to do with it.

Good luck.

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: )
Thank you anyway

I’ve made it, but as @martinsiegrist noticed the panels are twisted so in some locations the result is not very nice - not to say impossible to build.

The vectors help checking which profile have an angle and which don’t.

Edited with a more accurate version :

  • changed loft to Sweep2 so the vertical beams have matching normals
  • grafted the perp frames correctly
  • added sorting left/right for the normals, even though not necessary on this geometry, coule prove useful in the future.

HullDesign.gh (275.8 KB)

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Whaaa… Thank you so much for your time. Hope you enjoyed it : )
I have difficulties translating what you did but this is fantastic, can’t wait to study it.

About the twisting thing. My brain has difficulties conceptualise this and I don’t know the math behind it, but each panel being a loft of 2 curves. If I can loft them, I should be able to build that surface shouldn’t I?

In boat design, this method is called “radius chine” or " Radiused Chine":


I’ve used the method myself in this Pacific proa design:

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Thanks for link! Interesting stuff…