Curves workbench

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drmacro
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Re: Curves workbench

Postby drmacro » Sat Oct 17, 2020 1:13 pm

GlouGlou wrote:
Sat Oct 17, 2020 12:54 pm
MixedCurve carry out a curve with curvature on U on V. So, the sweep is turning around the path. (use comb to see that)
But if you set Angular deflection = 10 or less and deviation 0,1 or less for the sweep, the pipe look like nice. ;)
Yes, I did see that with the comb. Thanks.

Interestingly, if you change the sweep profile to a hexagon, the surface is smoother than with a circle...
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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Sun Oct 25, 2020 9:24 am

Proposal for new feature:
a sweep with 2 points (or more) and the path. There are not tool to do that directly in freecad I guess.
Could be an possibility for PipeShell?
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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Sun Oct 25, 2020 10:11 am

Proposal for new feature:
use a cloud point (point wb) to make a surface with "Approximate to Nurbs" as a birail cloud.
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Pauvres_honteux
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Re: Curves workbench

Postby Pauvres_honteux » Wed Oct 28, 2020 7:02 am

GlouGlou wrote:
Sun Oct 25, 2020 9:24 am
Proposal for new feature:
a sweep with 2 points (or more) and the path. Could be an possibility for PipeShell?
Trying to wrap my head around your proposal and got to this (probably wrong) conclusion:
the purple curve shall somehowe be extruded and be made to pass through a pair of (arbitrary?) points in space?
Then the end tangent vectors from the original curve shall be extracted and parallel translated to their corresponding points in space?
Then a connecting curve shall be made between the "space points" with tangency direction stipulated by them previously transformed vectors?
.
Intrigued as I am, may I also ask what the use case for this is?
.
Perhaps a series of pictures (cartoon style) showing the work process would make it easier to understand?
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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Wed Oct 28, 2020 9:52 pm

If I make 2 extrudes with the two vertexes, I get 2 lines. Then a sweep is easy to do, but need several operations.
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Pauvres_honteux
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Re: Curves workbench

Postby Pauvres_honteux » Thu Oct 29, 2020 9:49 am

Okey, now I get what you want!
You want to sweep a "stick" / "rod" / "pin" / line / vector along a curve.
.
You also want that "stick" / "rod" / "pin" / line / vector to be parallel to something and keep that parallelity along the whole curve.
.
So the remaining question is, do you assume the green curve already exist or not? If it already exist, then the problem definition is almost solved. "Only" the "stick" / "rod" / "pin" / line / vector direction remains.
.
If the green curve shall be created at the same time, it'll be, at a minimum, intriguing.
.
Did that sum up your request?
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GlouGlou
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Re: Curves workbench

Postby GlouGlou » Thu Oct 29, 2020 11:51 am

Yes. And the green curve is the result. Can be "extracted" with joincurve for example.
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Pauvres_honteux
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Re: Curves workbench

Postby Pauvres_honteux » Thu Oct 29, 2020 1:54 pm

Just to put your request in perspective, there are 21 different ways of sweeping in Catia...
And almost every one of them variants are missing. But one step at the time! No need to panic, we'll get there, sooner or later.

Will you create this feature request, or shall I do it? (yes, I'm missing this "sweep a stick along a curve" -variant as well)
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saso
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Re: Curves workbench

Postby saso » Thu Oct 29, 2020 2:38 pm

Here are a few more examples I made about this in the past, basic idea is to have a few basic profile shapes (ex line, circle and rectangle) available directly in the tool https://forum.freecadweb.org/viewtopic. ... 57#p324957
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Sabm01
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Re: Curves workbench

Postby Sabm01 » Tue Nov 17, 2020 4:20 pm

Problem : Approximate creates 2 curves

I created a bspline in a sketch.
Then I use discretize to create a string of points
Then I use approximate to create a curve from the string of points.

I found 2 curves created. Why?
Test_approximate.FCStd
(13.74 KiB) Downloaded 3 times
Thanks for your time,

Michel
Michel Sabourin (Sabm01)
www.simturb.com