3d tri axial ellipsoid how to in 2012 full version

[Anonymous]

I need to know how to draw this in 3d and then import into geomagic designs so I can save as a sldprt file so I can then create a mold cavity with it. It is a triaxial ellipsoid that measures 3.5 X 9.00 I usually use the geomagic program which was formerly alibre to create all my 3d shapes and then use a Boolean function to create mold cavities that I can then use my cam program partmaker to generate gcode. alibre will not create this particular shape exactly the way I want the closest I can get is a parabola slice function which is nothing more than a slice off the top of a bi axial radius. If anyone knows how I can create this in auto cad id much appreciate it. I do not have any experience in drawing off 2d in autocad i use it to generate dxf files that i then import into alibre to extrude and revolve to make the shapes i need..

[SEANT61]

Does "tri axial" imply different measures along all three axes?  If not, those dimension could be had by a "Revolve" operation on a half ellipse.

[Anonymous]

yes exactly imagine an elipse 3.5 X 9 top view .1875X9 front view and .1875X3.5 right side view.. i can send a dwg if you would like to lend a hand

[SEANT61]

Like this?  This particular solid was made with an add-in.  I could be approximated in AutoCAD with the LOFT command and some strategically placed elliptical arcs.

[Anonymous]

YES that is exactly what i need.. im sorry i dont know too much about add ins i can research this and then get back to you so you arent dealing with an idiot when trying to explain.. but please clue me in

[SEANT61]

By add-in, I'm referring to programming/software not native to the core application (AutoCAD).  The Exchange (http://apps.exchange.autodesk.com/en) is a repository for routines that add functionality to Autodesk products.

The Ellipsoid routine is currently unpublished. 

[SEANT61]

I'll revisit the routine this week to determine whether to post it here, or possibly submit it for publication at the Exchange.

[Kent1Cooper]

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@Anonymous wrote:

.... a triaxial ellipsoid .... If anyone knows how I can create this in auto cad id much appreciate it. ....

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I have something you might be able to use, that makes Domes as 3D Solids, including elliptical ones, including those with three different axis lengths.  It's IN PROGRESS, but it works, with the little provisos at the top of the file.  It makes only the top half of a full ellipsoid, because it was in response to someone wanting to make dome shapes, but if you want the full one, you can probably alter it to leave it full, or just mirror the result and join the two halves.

The sometimes issue at high precisions occurred when I called for 150 or 200 segments per quadrant, but at that kind of precision, manually applying Intersect afterwards worked.  At 500 segments per quadrant, it didn't.  On the other hand, another one worked fine at a precision of 400.  I don't know what determines whether it works -- it may be affected by the axis ratios involved, or it may just be an occasional fluke.

It's actually pretty much fun to watch it work.  At high precision, give it time to perform the Intersect operation.

[The zz filename beginning is just my little filename prefix that I use for things I'm still working on, so they'll all appear together in an alphabetical listing -- I remove that once it's finalized.]