Through curve mesh continuity

[st4r]

I'm having problems with connecting through curve mesh with body (body is made of extrude and sewed sheets, which are united),.to be precise with continuity between mesh and body faces. I have tried to set it to be G1, but it doesn't look good visually (at the place where sewed body touches extrude, mesh is too curved,...it is tangent, but it doesn't follow curvature of the body faces). Also G2 was useless because mesh was deformed (wrapped). I can't use G0 because mesh has to be tangent to body. Is there any other way to control continuity. I need some kind of mesh which looks like extension of the body surface and passes through sketches.

 

[JohnRBaker]

Without at least a picture of what you're attempting, it's hard to give any sort of advise. A part model would be even better yet.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[st4r]

here is the picture of a problem. green is a face of extruded part of the body (cylindrical), blue is face of sewed sheets (it looks like variable blend attached to extrude, green and blue are tangent to each other). they are united. mesh, which is orange has to be tangent to them. border line between blue and green face shows how curvature should continue on mesh, but instead i get this highly curved area.

 

[jerry1423]

if I understand you correctly, you cannot connect a surface (curve mesh) with a solid body - only sew surface to another surface, or unite a body to another body.

 

[JohnRBaker]

That picture is totally worthless since it does NOT show anything about what the model ACTUALLY looks like.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[st4r]

OK, sorry about that, here is the new picture with some additional info. It shows a quarter of a model. (I can't post model...) I hope it will be more clear. Yellow is face of revolve, blue is face of sewed sheets, green is extrude. these three are united. (red is just a face of that united body). blue face is also TC mesh and its role here is something like variable blend between revolve end extrude. It is tangent to them both. Orange is through curve mesh which has to be tangent to green, blue and yellow face of a (united) body. in that square is a detail which i gave you in previous picture, from a different angle. I am having problem with achieving smooth transition from body faces to mesh (orange). Thanks

 

[JohnRBaker]

Is the composite of the edges of the Green, Blue and Yellow bodies (where the Orange surface is to match with) supposed to be planar? If so, it might better to model your Green, Blue and Yellow surface a little 'long' (toward where the Orange surface will eventually exist) and then trim it back to a Datum Plane. Also it would help is you could provide a picture of the 'wireframe' view of this model (I mean the 'static wireframe', not the dynamic hidden-line view which we now call the 'Wireframe' display).

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[st4r]

Yes, that edge where mesh is supposed to meet body lies on a plane. I think I know what you mean,...will try that. Thanks.

 

[hudson888]

Let me guess some of the profile geometry is comprise of true arcs rather than splines. You may therefore eventually get a result that builds but for continuity you may continue to struggle and I can already see some torsion in the tan surface as pictured in your first image. Perhaps you need to check for continuity of the section string before you attempt to force the resulting mesh to apply continuity otherwise your surface internals may be so complex and poorly organised as to produce vastly inferior results. If for example you are using geometry in your section string that is only capable of being G1 continuous then the best you can expect of your mesh is G1 continuity, and then only if it manages to map the surface U/V curves with the bounding objects in some kind of sensible fashion. This is by no means automatically guaranteed and you may prefer on most occasions to rebuild your mesh in sections or at the very least insert cross curves that will help you gain control over the resulting shape.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum

 

[st4r]

I managed to make it a bit smoother by using (reversed) john's idea, except that I used intersection curve instead of sketch, for a first primary. It's not perfect but looks much better. I'll have to test it more. Thanks.

 

[st4r]

...and sorry for bad English.