11 Replies Latest reply on Mar 26, 2012 12:44 PM by Crispin Weinberg

    help making a brain

    Baldwin Goodell

      I have created some 3d brain models from MRI data and tried importing them into Solidworks but I am not very satisfied with the result because their native formats are mesh (STL or VRML) .  Instead I would like to instead create a Solidworks part directly.  I am making progress but it might be more work than it is worth.  I am hoping some experienced users can advise me if I should even pursue this project or offer suggestions to improving my method.

       

      My progress so far includes:

      I first imported MRI jpegs into SW and traced splines around the images and then lofted them together.  As you may know the brain has a very complex surface and I tried to loft detailed spline sections but SW would only allow me to create a very smooth loft instead.  So now I am forced to make cuts for each sulcus.  I have drawn 3d splines on the surface where the major sulci should be.  I think I now need to create planes along these splines and draw closed splines to create individual lofted cuts for each sulcus but this seems like a daunting task.  I did one sulcus this way and it does not look very good.  It would be nice to smooth the edges of the cut.


      I attached my part and a picture of what I want as a final result.

      Thank you,

      Baldwin

       

      PS.  When I did a search through the forum for "brain", I got a lot of references to "brain fart" but nothing related to a model of a brain.

        • Re: help making a brain
          Dennis Hvam

          Hallo Balwin,

           

          I think a google search might help you a bit:

          http://www.cadanatomy.com/brain-human-3d-solid.html

           

          There are alot of sites around the web with human 3D parts.

           

          Just my 2 cents.

           

          /Dennis

          • Re: help making a brain

            Baldwin,

             

            There are no solid models of the brain that I'm aware of. Zgote has some SW models available for purchase, but not the brain. They have a poly-mesh of the brain, as Dan has pointed out above, and it could be a good starting point to purchase it (if you can afford it) bring it in to SW using ScanTo3D and reverse engineer it using auto surfacing and manual surfacing - that's what I would do if someone were paying me to reproduce a very accurate SW model of the brain.

             

            Regards

             

            Mark

            • Re: help making a brain
              Matt McKendrick
              The only way to do this project is from scanned data.  That means a mesh, unfortunately.  There are reverse engineering software packages that will convert scanned data into usable solid geometry.  A quick look around the internet will yeild some results.  We use RapidWorks to convert our scanned data, but that is only 1 option.
              • Re: help making a brain
                Baldwin Goodell

                Thank you for all the help everyone.  I have already created a mesh model but since I don't have Scanto3d or RapidWorks I have not been able to save it as a NURB model.  Can anyone recommend someone whom we could hire to convert our mesh model into a Solidworks part file?  Thanks again, Baldwin

                  • Re: help making a brain
                    Neil Larsen

                    What is your purpose in wanting the detailed surface?

                     

                    Just for interest here are some links to Blender projects I know of for MRI type data, most likely there are (better) commercial solutions out there as well.

                     

                    http://blenderartists.org/forum/showthread.php?t=154372&highlight=voxel Kai Kostack's GLSL volumetric emulation - see the YouTube link.

                     

                    http://mke3.net/ see about 1/3 way down the page for voxel rendering of body.

                     

                    I'm pretty sure Rhino will import VRML and export as .3dm or .igs and you will be able to import into SW (demo has free 25 uses)

                     

                    edit: coincidentally there is a recent discussion at EngTips about SW and  voxels http://www.eng-tips.com/viewthread.cfm?qid=253455&page=1 which may or not be of further interest...

                      • Re: help making a brain
                        Baldwin Goodell

                        Neil,

                        Thanks for the useful links.  We want to have this model to improve the design process and for visualizing the final design.

                         

                        We already use MRI images that are cropped and saved as bitmaps that can then be loaded as SketchPictures every millimeter. This results in great accuracy but we do not have a simple way to view it like in Kai’s movie.

                         

                        But an easily viewed 3d model of the brain would be very useful. Of course the more detail the better.  I suppose there is a compromise between model quality, the resources SW requires to use the larger file and the effort required to make the model.

                         

                        Your link to http://www.dezignstuff.com/blog/?p=2550 was useful. I need to do some studying now but creating the model as a native SW part seems time consuming.

                         

                        There are several programs that can be used to create a mesh model from MRI data and simply importing this into SW does not work well because the file size gets huge. I suspect converting the mesh to an IGES before importing to SW will be the best option. I am uncertain how difficult it will be to get a quality NURB model this way though.  I guess Rhino would be a good place to start.

                         

                        For the final rendering phase, maybe it is possible to swap the brain model used for design for a more detailed version. I don’t know much about this yet but maybe Blender would be a good option.

                         

                        Baldwin

                          • Re: help making a brain
                            Neil Larsen

                            You know yourr present attempt isn't so bad really but you could spend more time making the splines follow the outline more accurately including the top groove.

                            I tried this myself and the loft will tolerate quite a bit of detail and deformation from section to section but the tight corners of underside lobe thingy gives trouble ie the loft failed to complete across all profiles in my all-in experiment with a geometry warning.

                            Perhaps you could simplify/skip across that difficult part and try forming that as a separate loft and use the boundary feature to patch them together...

                            Freeform may be useful to fine tune the humps and hollows afterward.

                            This solution may be 'good enough' without the complexity of the mesh or many patched surfaces.

                            HTH

                      • Re: help making a brain
                        Crispin Weinberg

                        Biomedical Modling is a SolidWorks Solution Provider for converting medical imaging data (CT, MRI, US, etc.) into SW.  The process involves segmentation in medical imaging software, followed by reverse engineering ( smoothing & meshing) as described above.

                         

                         

                        Take a look at http://www.biomodel.com/biocad.html for some examples.

                         

                        Best of luck,

                        Crispin