Tensile form from non-rectalinear mesh?

unhandled

#1

Hey guys i’ve been experimenting with kangaroo to develop tensile forms but i’ve hit a wall when using a mesh that isn’t purely a rectilinear plane. In the attached files are the script i’m using and the shape that i’m attempting to form into a mesh. For some reason the mesh input on grasshopper won’t except any cut or trimmed meshes and i’m not sure on how to proceed from here.

I’ve mainly been using the mesh plane tool to generate the mesh and using the trim mesh command to fit the desired shape but the script won’t accept it. Any help would be appreciatedFORM-FINDING-FOR-BASIC-SURFACES-RRT.gh (16.0 KB)
MESH FORM.3dm (45.8 KB)


#2

It looks like your mesh is a good one but extracting mesh edges shows a weird problem. When if you join the naked edges, there will be some unwanted extra edges left.
That’s why I’m not sure your original mesh is a good one but I have no idea about the exact reason.
It works fine when I reproduce the base mesh using your boundary though.

FORM-FINDING-FOR-BASIC-SURFACES-RRT_re.gh (58.7 KB)


#3

Thanks for the help, would you recommend that i just reproduce the mesh from the boundaries instead then? If so, is there a command in grasshopper to reproduce the x and y vertices (the grid on original mesh) on the new mesh itself as the points had to be on a vertex to be used to generate the tensile form?


#4


#5

Okay i’m really sorry for asking some probably basic questions (i’m really new to grasshopper) but the only reason i ask is that while those sliders do work, i kinda need some points in-between the edges and in the middle of each edge creating something similar to the work attached. TENSILE FORM.3dm (90.3 KB)
FORM-FINDING-FOR-BASIC-SURFACES-RRT 2.gh (20.4 KB)

As such i kinda need a grid such that i can actually plot these points on the mesh itself and manipulate them to create the form. Unfortunately, the only i’ve found to plot this grid is through the mesh plane command (lets you choose the no of x and y faces) but as i found at the start of the topic, this doesn’t work for non rectalinear meshes (which you helped solve).


#6

This may not be relevant, but a good general meshing strategy when working with membranes is to generate one SubD mesh using Weaverbird, from a collection of convex/closed polylines. This mesh can then be subdivided further (either using Weaverbird, which will subdivide recursively when adding more divisions), or the mesh tools from Kangaroo (which enables one to subdivide a quad-mesh linearly in terms of divisions):

180520_QuadMeshing_ConcavePolygon_00.gh (8.8 KB)