The Mesh to CAD functionality is transitioning the optimisation result from an STL-file back into a NURBS CAD-file. Therefore, a surface quad mesh is overlaid modelled on the optimisation result geometry . Patches and patches for bigger planar surfaces are merged intelligently.
The Retransition should be performed on a non-intersected optimisation result. After the Retransition a boolean intersection with the Design Space can be done to create all functional surfaces and sharp edges. The resulting NURBS CAD-Geometry can be manipulated of course by MSC Apex (Generative Design) or any CAD software. The Retransition ensures and simplify simplifies the continuing workflow to the FE-Reanalysis, further CAD modification and process simulation.
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Import a non-intersected optimisation result. You can find this file in your project folder: Project → Meshless Generative Design Scenario 1 Step 1.v1 → buildSpace_MC_MainData_Loop_64.stl
Create a NURBS CAD geometry with the Facet Body to NURBS Geometry Tool (Geometry Edit Tools)
Let the software determine a suitable Quad-mesh size
Choose your own suitable Quad-mesh size
Nurbs not fully generated. Status message: …
Use Geometry Cleanup tools
If necessary use the Filler tool to restore missing NURBS-Patches
Boolean Intersection between the NURBS geometry and Design Space either in MSC Apex Generative Design or MSC Apex
You can find a step by step tutorial here.