complex surface

[2ms1]

For me, since I'm a beginner surfacer,the following task is very complex and has me a bit stumped. This is the ol' hand I've been having problems with and puting on this board for months now. Well, I'm almost done. I have all the fingers, joints, etc.. everything done except connecting the bases of the fingers to the wrist.


I have done this boundary blend shown below and it's a beginning, but it leaves much to be desired especially in the areas of being continuous with the parts it is connecting.


Anyone have any suggestions on a better way to make a surface that connects the bases of all these fingers to the ellipsoid there that's functioning as wrist?


The last picture shows an additional pair of kind of top and bottom curves that Ihoped could be utilized somehow in order to get control of the top and bottom sides of surface and get tangency with the fingers. However, boundary blend does not seem to accomodate these extra curves because it only does pairs in two directions, not three and I don't quite know what other options are out there.


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Edited by: 2ms1

 

[dgs]

You're asking a lot of the geometry to go from a simple ellipse to a complex, undulating curve.


I think you might have better luck making that with 4 individual boundary blends, merged together with rounds at the intersections. That will give you more control of the 'trajectory' of each section.


Also, one thing that helps smooth our your othersurfaces and eliminate the many patches created by the curve segments is to use approximate curves. After your curves are created (sketched, projected, whatever), make a copy of the curve. Here's how:
<UL>
<LI>Select the curve entities, not the curve feature. You know you've got the entities if the curve highlights in a fat red line. Skinny red line means you've picked the curve feature.
<LI>Select edit -> Copy and then edit -> paste
<LI>On the dashboard change from 'exact' to 'approximate'. Don't let the 'approximate' worry you, the resulting curve will have the exact same geometry as the original, except it will be a single spline entity instead of many smaller entities.
<LI>Repeat for each curve.</LI>[/list]


Create your boundary blend from the approximate curves and your surface will be a single 'patch' instead of many.


Approximate curves only work if all the curves segments are tangent.
Edited by: dgs

 

[design-engine]

keep it simple... Smart people are smart because they keep it simple. Notice all the control vertices you have steming from the fingers. You have made the model complicated just from your plan of attack.
Edited by: design-engine

 

[jefferyanderson]

2ms1, would you be willing to post the model so we can download it and look at it?

 

[2ms1]

I only wish I wasn't using the student edition. I'll post the file anyway, just in case someone has both versions or would find the igs file useful. I have commercial version too, but this file was started in the student version


2007-11-01_114408_handbase.prt.zip


2007-11-01_114509_handbaseIGS.zip

 

[2ms1]

Anyone have any suggestions on get the top and bottom of the surface to be tangent/contuous to the end opposite the ellipse (the fingers)? I continue to be unaware of any way to do this with VSS, yet boundary blend only allows curves in two directions.


I would really like to be able to use curves like the two labeled 3 and 4 in the last image above. They are tangent to the top and bottom surfaces, respectively, of the fingers, so they'd be perfect way. I just don't know how to get them in the game.


Other than this problem of not being able to get the bottom and top surfaces continuous with the parts they are connecting to, I'm basically happy with what I have. However, what I have right now isn't acceptable.