Curves workbench

Post here for help on using FreeCAD's graphical user interface (GUI).
Forum rules
and Helpful information
IMPORTANT: Please click here and read this first, before asking for help

Also, be nice to others! Read the FreeCAD code of conduct!
drmacro
Veteran
Posts: 8870
Joined: Sun Mar 02, 2014 4:35 pm

Re: Curves workbench

Post by drmacro »

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...
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
User avatar
Vincent B
Veteran
Posts: 4713
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

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?
Attachments
Capture.JPG
Capture.JPG (16.36 KiB) Viewed 1494 times
sweeppoints.FCStd
(8.15 KiB) Downloaded 38 times
User avatar
Vincent B
Veteran
Posts: 4713
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

Proposal for new feature:
use a cloud point (point wb) to make a surface with "Approximate to Nurbs" as a birail cloud.
Attachments
Capture.JPG
Capture.JPG (57.18 KiB) Viewed 1479 times
User avatar
Pauvres_honteux
Posts: 728
Joined: Sun Feb 16, 2014 12:05 am
Location: Far side of the moon

Re: Curves workbench

Post by Pauvres_honteux »

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?
User avatar
Vincent B
Veteran
Posts: 4713
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

If I make 2 extrudes with the two vertexes, I get 2 lines. Then a sweep is easy to do, but need several operations.
Attachments
Sweep_with_extrude.FCStd
(12.51 KiB) Downloaded 41 times
Capture.JPG
Capture.JPG (20.6 KiB) Viewed 1379 times
User avatar
Pauvres_honteux
Posts: 728
Joined: Sun Feb 16, 2014 12:05 am
Location: Far side of the moon

Re: Curves workbench

Post by Pauvres_honteux »

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?
User avatar
Vincent B
Veteran
Posts: 4713
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

Yes. And the green curve is the result. Can be "extracted" with joincurve for example.
User avatar
Pauvres_honteux
Posts: 728
Joined: Sun Feb 16, 2014 12:05 am
Location: Far side of the moon

Re: Curves workbench

Post by Pauvres_honteux »

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)
User avatar
saso
Veteran
Posts: 1920
Joined: Fri May 16, 2014 1:14 pm
Contact:

Re: Curves workbench

Post by saso »

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
User avatar
Sabm01
Posts: 58
Joined: Sun Jun 21, 2020 7:43 pm
Location: Canada
Contact:

Re: Curves workbench

Post by Sabm01 »

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 57 times
Thanks for your time,

Michel
Michel Sabourin (Sabm01)
www.simturb.com
Post Reply