Double Spiral sculpture "Wonder" (up and down)

[Joseph_Oster]

This is a cool double spiral sculpture by U.K. “Designer & Inventor” Tom Lawton. It’s on a rotating base so appears to go up and down at the same time. Done using parametric CAD.

Wonder :: Tom Lawton

This Sculpture Looks UNREAL!! 😱 #Shorts

WONDER - This Object Looks Impossible!!

[Joseph_Oster]

Needs refinement but not too bad…

full size

full size

[laurent_delrieu]

Hello
There was a discussion on double spiral some time ago. But didn’t know it will give a nice effect when turning.

Spiral tool for grasshopper

Hi Laurent, I there a way to make the spiral overlapping, like in the attached image? [overlap]

[saeed_hasan_zadeh (saeed)]

where were you was Laurent!

[Joseph_Oster]

@laurent_delrieu

There was a discussion on double spiral some time ago.

Thanks, looks interesting and relevant but unless I get stuck, I don’t want to ruin the fun of discovery by looking at other code. I’ve made good progress and am pleased with how it looks. I have separate parameters for inner and outer radius (5 and 8), inner and outer “turns” (3 and 1 in this animation), ‘DivPts’ on the base circle (43) and height (15).

full size

Top view:

full size

I suppose I should post the code but don’t want to spoil anyone else’s fun.

Turns in this one are 2 (inner) and 1 (outer) with layers reversed in GIMP:

[markz]

Nice work Joseph. And thanks for making me aware of this sculpture

[Joseph_Oster]

I replaced the Pipe with an elliptical cross section that twists based on distance from centerline. Not bad but doesn’t match some artistic details of Tom Lawton’s sculpture.

wonder_2023Aug27b.gh (37.8 KB)

In a different version, I’m exploring the Z coordinate of each perp frame (cross section), so it is flatter at top and bottom and steeply banked at the vertical middle. I’d rather avoid the complexity encountered in a recent thread, banking a figue-8 ramp.

8-shaped ramp - double helicoidal ramp?

I’m a little surprised that it’s so difficult to get a ramp that isn’t “wonky”, though again, I believe the dimensions and small radius value of the inner circles play a role. I rewrote the gray group to reliably generate a figure 8 base curve based on a plane, and ‘Apart’ slider (182.5 units between center points) and two radii. Then rewrote the yellow group to implement a smoother bank angle. As you can see by the curvature graphs (dark gray group at the bottom), they look better using smal…

[markz]

in his sculpture, appears he has a total of 1.5 periods, or 1.5 revolutions’, of each spiral

[Joseph_Oster]

@markz

in his sculpture, appears he has a total of 1.5 periods, or 1.5 revolutions’, of each spiral

Tricky, isn’t it? I’m not so sure. This is version ‘Aug27b’ with ‘Turns1’ and ‘Turns2’ set to 1:

This is a hasty hack that implements half turns, version ‘Aug27d’ with 1.5 turns for both spirals:

wonder_2023Aug27d.gh (44.1 KB)