Catia Quick Surface Recognition Module & 3D Scanned Data

[anyoldname]

I am trying to convert some .stl files from a 3D scanner into a solid models. As most of you will probably know, stl files do not define a solid or surfaces, they are just a collection of points & triangular elements in space so they can't be used directly in a model. Therefore, the stl needs to be processed to form either a solid or a surface set that completely encloses a volume.

The best method we have so far is to import the .stl into Catia and process them with Catia's Quick Surface Recognition (QSR) module but this is very user intensive. Each surface section needs to be selected, given a type classification (plane, cylinder, sphere etc) then stretched to overlap its neighbouring surfaces. Once the same operation has been performed on the neighbouring surface, the surface sections can be merged together and an appropriate fillet radius added to the joined edge(s).

QSR's Powerfit function can fit a surface to contoured geometry but it only seems capable of doing this with relatively small sections of the model and the resulting surfaces don't join up particularly well (they often tend to curl up at the edges etc)

Our .stl files have a resolution of 0.7mm, I'm wondering if we increased the point spacing whether that would make the geometry easier for the Powerfit function to handle, does anyone have any experience of this?

Also, I once saw a demonstration of a software system called Rapidform, it was able to apply surfaces to complex .stl geometry in a much easier to use method, its approach was more like throughing a blanket over the point cloud. The operator had to give the software a few clues as to how the contours of the geometry flowed but after that the software could quickly generate a best fit surface through the point cloud.

Does anybody have any suggestions of a better method or know of any other software that would need less operator input to get the scanned stl converted to a solid body?

All advice will be appreciated.

Thanks.

 

[Azrael]

Usually you start with DSE, Digitized Shape Editor, it's a workbench for working with cloud data. Add the stl through the import cloud function in DSE and then you can start to filter and clean it, smooth it, fill gaps, split it up into different areas... what ever you see fit... when that is done go to QSR and create the surfaces, powerfit should work like a charm if the data is clean and nice.

But there is a quick way Import the scan data (stl) into DSE, use "free edge" and "Mesh cleaner" to check or fix the scan. Switch to QSR and use "Automatic Surface"