Voronoi 3D for centerline of bifurcation, the last mile to go

Grasshopper
1

Hi everyone,

I need create the centerline of a bifurcation shape.

first
first1410×1175 251 KB

I tried to use Voronoi 3D and here are the steps:
1, create radom points on the bifurcation;
2, build Voronoi 3D cells, then explode all cells into lines;

second
second1576×1316 316 KB

3, fillet out the lines inside the bifurcation;
4, using line length to fillet out the lines furhter.
However, I can only get the lines showing the centerline trend with lots of “noises”.

final
final1337×1132 54.7 KB

Attached is my GH file. Any suggestions and ideas are so appreciated since this task (to create 3d centerline) has confused me so many years!
Voronoi3D-centerline-R7.gh (237.6 KB)

2

Hello
here is my way, putting an integer value at each naked edges. Smoothing the weigths, then trying to find the circle …

image
image1021×806 146 KB

image
image1193×795 131 KB

image
image1145×812 139 KB

image
image765×696 40.9 KB

Still need to link the ends, sort end points choose the one that are far from the naked edges, find the centroid, connect the centroid
You will need Nautilus plugin
centerline mesh.gh (79.9 KB)

Seems to work with 4 tubes

image
image765×696 4.91 KB

1 Like
3

Thank you so much for your prompt reply, @laurent_delrieu!
I am studying your code. I have Nautilus plugin (it’s so cool).
Actually your method is a little beyond me and I need more time to understand each step.
I will be back to you soon.

4

I understand, some months ago I had no idea of these tools. Globally you could look at tween curve discussions.

There is a slight problem with Proximity has it searches for 2 points, it is OK if points are inside the curve but if they are ends it generate some problems. Topologizer from Daniel Piker could help.

And also your problem is more a Medial Axis problem, there was some discussions on it in 3D but I think it is more appropriate for Solids.

1 Like