I’m working with a 3D scan of a dome and I need to generate a surface from it to start developing a panelization (modulation) system.
I’ve tried extracting a mesh directly from the scan in Rhino, but it’s extremely dense and complex to work with. I also attempted to extract points and rebuild a NURBS surface from them, but the margin of error seems too high.
Has anyone faced a similar situation? What workflow or tools would you recommend to obtain a workable surface from a 3D scan for this kind of geometry?
The original scan file is extremely heavy, so unfortunately I can’t share it here. If anyone has suggestions on how to handle or reduce the file size efficiently to make this process more manageable, I’d really appreciate it.
I create surfaces from photogrammetry scans of boat hulls. My general approach is to import the mesh into Rhino, orient and scale it, and trim it if needed. I look at the shape and decide how to divide it (if needed) into a set of surfaces. Then I contour the mesh to create a set of polylines, and use the polylines to create surfaces. The next steps depend on the shape and surface patch arrangement, but typically involve creating edge curves, creating initial surfaces from the edge curves, and then using Patch to pull the initial surfaces to the contour curves. I usually use Worksession with the mesh in one file, the contours in a second file and the model in another file.
If you regularly work with 3d scan data, I highly recommend you to buy a program called Atangeo Balancer nPro 2.0. Opt for the “Non-Commercial” license which comes at half the price ($72). That program works super fast with meshes and is capable of reducing large meshes for second. The preview is dynamic, which means that the changes of complexity are immediate, so you can easily decide what percentage of polygon count reduction is good for your purposes. Then you export the optimized model as STL and import it into Rhino.
Another solution may be using a plug-in for reverse engineering called “Mesh2Surface”. You can download a trial version for free which can be used for a limited period of time. It’s fairly easy to use this plug-in and build NURBS surfaces on top of the 3d scan model.
A 3rd option is to use a plug-in called “Sybestrack”. It’s also capable of building NURBS surfaces onto 3d meshes.
A 4th solution is to build a NURBS surface and orient it normal to the 3d mesh, then rebuild the surface to 50x50 control points, then turn the control points on and use either the “Pull” or the “Project” command to project the control points over the 3d mesh. The process is fairly easy. Then select the projected surface and rebuild it to a simpler surface such like 6x6 control points or whatever works best for your shape.
