CAD Model Transfer Process

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Sketchup to CAD

Discussion

From DesignCAD.com:

  • If you have used SketchUp, you know that it works all the time in the 3D environment unless you tell it otherwise. SketchUp encourages you to build your model in perspective mode and to apply materials to surfaces as you go. Despite this level of sophistication, SketchUp still operates very quickly, even on fairly modest computer equipment - there is no noticeable deterioration in performance as you add new parts to the model.
    • SketchUp can do this because it builds its models using triangular meshes; many surveying packages do the same when they are asked to create terrain models of land surfaces. Complex 3D entities such as Coons patches, surfaces of revolution and so on which are used by software such as AutoCAD, IntelliCAD and MicroStation are not used.
  • This fundamental difference in storing model geometry places severe limitations on the model when it arrives in the CAD environment. The figure below shows the warehouse model above in the AutoCAD environment after we had exploded it and selected one of the faces. Note the appearance of many triangles. Incidentally, AutoCAD translates these triangles to to 3DFACES.
    • To See Figure Below, Click Link Above to Source and go to Page. 4
  • To sum up, we suggest that movement of models should be towards SketchUp from your CAD software, not the other way around.

Possible Solutions

Open Source and/or Free

Insert here if found. A tentative process for transferring 3D CAD Models between different platforms would be through Autodesk's free FBX Converter. This needs to be investigated however.

SKP Import for Inventor creates trimmed planar surfaces for each triangle/quad and knits them together to create a body. If the polygon mesh is closed (i.e. it does not contain boundary edges) then SKP Import for Inventor will create a closed body feature, otherwise an open surface will be created.

  • Downside:
    • Costs $249 for single non-updateable version, $299 for subscription ($50/yr after first year), which includes updates for new versions of Inventor.
    • Not open-source or super distributable to the "144 Seeds" -- but then again, neither is AutoCAD Inventor.
  • Upside:
    • We only need one license to bring all the Sketchup files created by the masses into CAD. i.e. any collaborator with a great design could send us the Sketch-up file and we'd be able to turn it into a professional CAD file with our one license.
    • Converted files could then be distributed in CAD format to the masses with drawings, models and all the rest (as well as the source version built in Sketchup).
    • Simple and easy to use.

CAD to Sketchup

Discussion

Possible Solutions

Open Source and/or Free