Question New surfaces and new solids of reduced model after optimization with beso to CGX or other tool?

Tool interfaces
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Question New surfaces and new solids of reduced model after optimization with beso to CGX or other tool?

How to make? The outer nodes of the results are points or near a new outer surface.

I see here Matthek or levien with her splines.
Levien:

see code, phd and Inkscape spiro Tool

It is a simple construction with triangles. First is 45 degrees. Next points and triangles are constructed with circles.

Matthek see

„Zugdreiecke“ in german is here the simple concept.

Best is a tool with CGX to be in eco system of calculix.

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Well, there is already shape optimization implemented in cccx itself. You should have a look at:

5.17 Optimization of a simply supported beam

In the manual.

Topology optimization on the other hand is available in free ad with a BESO implementation.

I started to develop the SIMP method within cccx and python. Some results are available here:

I’m still working on the publication andd release of the code.

Best regards,

Stoli

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For those who don’t read German, An English paper showing Prof. Mattheck’s tensile triangles idea can be found here.

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Here is my theme with results from beso or your tool to calculate a new part or new parts with new surfaces.

and in next iteration a remeshing of this new solid or solids and FEA of this model as final.

The product is in best case ready to 3D printer or other production processes.

Best world is an automated workflow with important parameters.

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I have to admit that, unfortunately, I don’t quite understand exactly what you want. Is it:

  1. Do you have a component or an enclosed space, and want to optimize the component so that it fits into the design space and is as light as possible? Then you need a shape or topological optimization method. The on referenced by stoli looks promising.
  2. Do you have a component that is mostly properly dimensioned but has local stress peaks that you want to reduce? Take a look at the CAO method in: C. Mattheck, Design in Nature
  3. You’ve performed an optimization and want to convert the result (which is probably closest to an STL file) back into a CAD model? That’s probably the most difficult challenge. I’m not aware of any way to automate this process. It’s the same issue as converting 3D scans into CAD parts. It probably won’t be possible to avoid manual reverse engineering.
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Matthek triangle method is a potential smooth algorithm to extract new good surfaces after topology optimization in beso or other tools.

Also levien splines can be attract to the outer nodes by beso result model.

At the end of such a module you can make a new solid by surfaces and then mesh this, calculate this and perhaps you go to end or again in beso,

second: It is possible years or decades to implement both splines in CGX or other calculix postprozessors to produce good models with good bionic curves instead of edges or circle curves.

so often you do not need BESO or other optimizers with a good first model.

Third: You are free to have a more genius idea to make a module in beso or calculix or anywhere to a very good or best cad-model after beso result.

greetings after eating a Easter egg.

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I actually wrote a script a long time ago that generates smooth CAD surfaces (NURBS) from STL files. See the screenshot: on the left, the Blender Monkey “Suzanne” in Blender as an STL file, and on the right, in a CAD program as a NURBS surface model.

STPE
STPE695×291 66.5 KB

Unfortunately, I never got the script to the point where I could release it to the public. It probably wouldn’t work with the current version of Blender either. It wasn’t very efficient, and could only convert a few hundred polygons; otherwise, the conversion took several hours. Plus, the mesh had to be of a certain quality (as the saying goes: garbage in, garbage out).

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Perhaps you can verify your project to reduce runtime of your algorithms.

It must not be extra good in first iteration.

A second or third iteration in beso with remeshing and FEM is possible in an automatic workflow.

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If your goal is simply to (re)mesh an STL file generated by an optimization simulation in order to do another simulation with it, you might also want to take a look at the GMSH createTopology feature:

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There are unchanged outer elements with their surfaces and fixed surfaces and her connected

So this should be transferred as information for complete iteration.

The first building room is here also limit and is important for beso.

And sometimes also load conditions like pressure or heat fluxes must transferred.

so it is not simple in detail.

but a first prototype can ran without this features on way to perfect tool.

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Gmsh and his feature can be used here:

I see here a tool pygccx as possible workflow with beso and gmsh:

It supports many commands of calculix, but not all.

Second tool:

GitHub - drlukeparry/pyccx: A library for creating and running 3D FEA simulations using the opensource Calculix FEA Package. · GitHub

it can handle 3d and new 2d problems with python,

both tools support not all calculix keywords and elements. PyCCX is more actual than pygccx.

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@Nobody-86: the result on the "monkey Suzanne picture is very impressive; I’m wondering if the work is based on the litterature (if so, do you accept to share the sources?), or on your own developements?

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Thank you very much for the compliment. I didn’t use any specific literature, just my own ideas and the manuals for Blender and gmsh (which I use as a background process for the conversion).