Alligning curves to surfaces

[Vertex_Assassin]

Hi, I've just joined this forum and I've already got a problem. Does anyone
know how I can allign a curve to a surface with curvature continuity? I need
such curves in order to create a curvature continuous fill surface dangling
from a surface edge.

 

[ttraser]

You can create curves on surfaces with intersecting planes or surfaces, create edge curves on the edges of surfaces, or you can create a fill/patch surface by selecting the edges of the area you care to fill. Do you have an example of what you are trying to do?





good luck,

 

[Vertex_Assassin]

Ok I've made a screenshot of the problem.

http://skildor.deviantart.com/art/SW-problem-1-66826908

The fill surface bounded by the green curves (a surface edge and 2 sketch
curves) refuses to have C1 or C2 continuity with the surface it's joined to. In
essence that's what I'm trying to do, without having surfaces edges all
around.

My original question was basically how to get the U-shaped curve to have C2
continuity to the surface it's linked to.
Edited by: Vertex_Assassin

 

[ttraser]

split the u shape curve into a top/bottom, then generate two lofts, top/bottom, then sew them all together. Is that what you mean?





confused...

 

[design-engine]

no... you double click on the tag.With 2007 version of solidworks you now have the boundary surface (i feal sorry forthe poor solidworksusers of yesteryear because that is new with 2007)


The first time you click you get vector direction. thesecond time you click you get tangency. thethird time you get curvature.

With the surface loft tool you have to get into the Start/End Constraints options to mess with levels of tangency.


I have discussed g1 tangency and g2 curvature in detail on the proe forum. search a class surfacing and you can read more. There I get into the calculus and issues of how light reflects off various levels of tengency and curvature issues with respect to Alias Studio and Pro/ENGINEER. Solidworks is not far behind now days which is why I am pusing the limits with solidworks these days.


keep the surfacing questions coming.
Edited by: design-engine

 

[Vertex_Assassin]

Are the aqua coloured curves the loft profiles? I've gotten back to SW today after a busy week and decided to try my hand at getting a surface appended to en edge with C2 continuity across the seam, like you've drawn.


The method you've described here almost solves the problem, there's only one special case left that I can't solve. I'll post a diagram as soon as I'm behind my own computer again.

 

[design-engine]

the correct term is g2 not c2 continuity. 'G' i think is for the mathematician who developed the calculus for magnetic fields. Gaussian

 

[Vertex_Assassin]

Alright, the loft technique works great to append surfaces. Now here's the final problem I have with this kind of surface: I can't use a guide curve to control the surface. In the screenshot you see a green curve, which is my guide curve. Since the grey surface has G2 coninuity with the green surface, the guide curve can only be used when it also has G2 continuity with the surface. But when I add a relation between the curve and the surface I only have one choice: 'tangent'. This is my original problem actually.


http://skildor.deviantart.com/art/SW-trouble-67497488


The only workaround I can think off is to control the green surface with another guide curve, and allign the guide curve to this curve with curvature continuity. Is that good idea?

 

[design-engine]

I guess I still don't fully understand what you trying to do. First let me say that continuity or tangency both are only important at where to curves or two surfaces join. Both Pro/E sketch and Solidworks Sketch tools only let you evaluate a comb plot on one curve or another. Silly notion and worthless tool because that evaluation needs to be on both curves with the importance on the brake in discontinuity at the comb plot. Calc I and II for the calculus folks.
<a href="http://boards.core77.com/viewtopic.php?p=84743#84743%20%20" target="_blank">

http://boards.core77.com/viewtopic.php?p=84743#84743</a>
Started this thread on this other board if your interested
in surfacing.