Perforated Mesh: How can I cut mesh with curves and other

Hi,

I'm working on perforated mesh but I'm relatively new of Grasshopper and I've got some problems. I seen tutorials and other discussion but I didn't found what i need.

I've a mesh and I need to realize something like this on my mesh:

The patther on mesh must have a gradient of opening of cells from edge to inside of mesh. I need to control this gradient with a polyline attractor drawn directly on mesh mesh surface.

I'm in difficult.
Unfortunately I can't upload here my project because is reserved industrial prototype.
Have you any suggestion for me? Link? Tutorial?
I've found tutorials with NURBS Surface and with BREP but I haven't found tutorial for mesh.
For example: When I've packing my shapes on the mesh how can i cut the mesh with this shapes lines? On rhino there is a SplitMeshWithCurve comand but in Grasshopper where is this comand? This command is for one curve at time, i need to cut my mesh with all curve in one time.

Thank you
Luca

Replies to This Discussion

Permalink Reply by Petras Vestartas on June 18, 2017 at 3:18am

Forget cutting stuff. Operate on mesh faces.

Just create diamond shape grid of meshes within panels and inset their faces inside, weaverbird will do the job with the frame component.

Permalink Reply by Luca Borro on June 18, 2017 at 4:27am

Hi Petras,

thank you for suggestion.

I'm working on this but i need to control density of structures by an attractor curve:

Only possibility that I have is a triangulate pattern? If, for example, I want to obtain circle pattern on my mesh surface? How can I do it?

Permalink Reply by Luca Borro on June 20, 2017 at 2:33am

Any suggestions??? Thanks

Permalink Reply by Luca Borro on June 20, 2017 at 9:10am

Thanks
It is good. I tried it a few days ago but I did not find a system for extruding the curve perpendicular to the mesh face. I tried with FaceN component but nothing appears.

Ideally I need to obtain only the faces of mesh that are intersected by curve, then I need to use these like as a surface to determine a perpendicular direction of extrusion. If I don't take the face that is interesected by curve GH take all the faces of the mesh and the calculus don't succeed.

Permalink Reply by Luca Borro on June 20, 2017 at 8:54am

Hi Tom, thank you for your reply.

When i told "reserved industrial prototype" I meant that the project is a medical project in which files are mesh from body scan and no other type of surface can be used.
An alternative could be a manually reconstruction of a NURBS surface from original MESH but this work is very very long at do it every time I need is impossible for me.

I tried to split mesh by mesh but I obtain only curve and I couldn't reconstruct a surface (for example a loft surface) from these complex curves.

An example of I want to do is this:

But I need to apply this to another parts of the body and I need to define the porosity of the geometry. The holes on the mesh must be very small on the edge and more big inside.

The geometry of the holes must be able to be defined by myself (circles, hexagons, squares) and no not necessarily must be a voronoi pattern.

Thank you for your suggestion.

Permalink Reply by Kim hauer on June 20, 2017 at 6:23pm

I just had a brilliant idea:

1 Use Marvelous Designer. Marvelous Designer is used to make clothes for 3d figures. Simple shapes are automatically wrapped around 3d geometry, be it a hand, arm or an entire body, if you chose.
2 Save the obj
3 Import 2 into Rhino
4 Use GH to create the voronoi skin from 3

5 Now you can end up with a voronoi carpal tunnel hand cast as pictured above.

Permalink Reply by Luca Borro on June 21, 2017 at 12:59am

Hi Thanks for your reply but I don't understand why I should create a mesh from Marvelous Designer since I already have my starting mesh. Can you explain me better your idea? THanks

Permalink Reply by Kim hauer on June 30, 2017 at 4:04pm

Yikes! I had forgotten that changing a mesh to brep to voronoi, is not possible in GH, better to use Meshmixer.

Permalink Reply by Luca Borro on June 30, 2017 at 4:13pm

Thanks, but with Meshmixer I can not control any aspect of the mesh.
For example I want to make the mesh thicker in some specific spots, 
with Meshmixer I can not do it...

Permalink Reply by Kim hauer on July 1, 2017 at 9:12am

to find out how! have a look at you tube

type: meshmixer voronoi

Permalink Reply by Kim hauer on July 1, 2017 at 3:08pm

So in Marvelous Designer I can use any avatar part that represents the human body, then create a clothing mesh that covers the part I'm interested in. Save the obj mesh.
In Meshmixer I can manipulate that obj mesh. Using the mouse I can paint over the mesh where I choose to increase mesh density or reduce mesh density. In the Edit menu I choose The Dual Edge (voronoi) pattern, that I now apply over the newly painted mesh.

So the challenge now is to 3D print cotton or linen like fabric, instead of using the tradition crocheting or knitting methods. :)