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Surface problem, need some suggestions.

Hello Surface Gurus,

I've got this surface that is driving me crazy. I've attached some images to help with what I will try to describe. The first image (patch-06) shows what I am trying to do. Surface by boundaries with curvature constraints all around. The surface works, but I get this ripple going across the surface. The 2nd image (patch-04) kind of shows that. In an attempt to smooth that out, I tried adding another curve along that direction. See image patch-01. The surface looked better, but I could not get a curvature constraint on the left boundary. But I could get a tangent constraint. Although it looked better, it really wasn't when I analyzed it, see image patch-05. Another problem that showed up after I did that was the surface boundary on the right no longer looked tangent/curvature continuous, see image patch-02-2, even though it is constrained as such.

If you have some tips for me I would love to hear them. I'd be happy to send the file to those who want it to see what is going on a little more closely.

Thanks,

-Victor
 

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Hello Victor

first - IMHO - to me your patch is over constrainrd, I mean selected constraints(Curvature) do invoke many of problems you`re trying to solve(smoothness)

Get rid of them, and replace them with tangent ones.

second - I would divide your patch into smaller ones, in example two patches. Partial line should go through 3 points you used in boundary blend

you can send a model to me for evalaution - [email protected]
 

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Last edited:
How did u made second curve in first picture. With out full details of the surface u cant make an intermediate curve to get smooth surface. Can u attach the surface
 
Hello Jacek,

Thanks so much for your comments. I will try to answer/explain why I did what I did.

1) The surfaces need to be c2. The tangent constraint will not give me the results I need. I realize it can introduce problems, but most of the other boundaries are c2.

2) I tried splitting up the surface, but the free end on the 1st half ends up having a condition that makes the next surface look funny trying to be tangent/curvature to it.

I sent the model to you. Thanks for taking the time to look at it.

Regards,

-Victor
 
Hello j.s.

The second curve was created by 1st creating a datum plane, then creating points at each end that intersected the boundary curve and the plane. I attached an image of the curve sketch. I added that curve because I needed the surface to bump out more. Without it, the surface was a little to flat, and it actually had a much worse condition. Adding that curve made it look a lot better.

curve_def-01.JPG
 
designengine (Bart?),

I tried doing that with undesirable results. I decided to try a different approach altogether. So far it's looking good, but I will be introducing a whole different set of problems. I haven't gotten to that bridge just yet, so we'll see what happens.

Thanks,

-Victor
 

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