Constrain a point in a b-spline.
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Constrain a point in a b-spline.
Hello forum members,
OS: Ubuntu 21.04 (ubuntu:GNOME/ubuntu)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.
Build type: Release
Python version: 3.9.2
Qt version: 5.15.2
Coin version: 4.0.0
OCC version: 7.5.1
Locale: English/United States (en_US)
I am a relatively new FreeCAD user and have been trying to follow a tutorial which details how to model an a380 airliner.
Link to tutorial: https://www.youtube.com/watch?v=dRCKmc0ZxBk
This tutorial is for solidworks, however I figured it should all be possible to do in FreeCAD. Unfortunately, I have come across an issue at 23:14(tutorial timestamp). I am unable to constrain the B-spline as shown in the tutorial. I have attached the file which I am working on. I was wondering if anybody has a solution to my problem.
Thank you in advance
OS: Ubuntu 21.04 (ubuntu:GNOME/ubuntu)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.
Build type: Release
Python version: 3.9.2
Qt version: 5.15.2
Coin version: 4.0.0
OCC version: 7.5.1
Locale: English/United States (en_US)
I am a relatively new FreeCAD user and have been trying to follow a tutorial which details how to model an a380 airliner.
Link to tutorial: https://www.youtube.com/watch?v=dRCKmc0ZxBk
This tutorial is for solidworks, however I figured it should all be possible to do in FreeCAD. Unfortunately, I have come across an issue at 23:14(tutorial timestamp). I am unable to constrain the B-spline as shown in the tutorial. I have attached the file which I am working on. I was wondering if anybody has a solution to my problem.
Thank you in advance
- Attachments
-
- a380_model.FCStd
- (557.17 KiB) Downloaded 25 times
Re: Constrain a point in a b-spline.
Sketcher B-splines cannot (yet) be defined to go through certain points. You, however, try doing it with Draft splines. You may first have to create DatumPoints lying on the curves and the planes.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
Re: Constrain a point in a b-spline.
I find that drawing D-wires/polylines and converting them to splines makes interpolated splines efficiently.
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- Posts: 3
- Joined: Sun Jan 23, 2022 5:34 pm
Re: Constrain a point in a b-spline.
Thank you for your replies.
I used the draft workbench after having calculated the necessary datum points. It all seemed to work fine, however, for some reason, I have come across the issue that my b-splines are not symmetrical along the z-axis (I have attached a screenshot). I was wondering if there is any easy fix for this.
Thank you in advance
I used the draft workbench after having calculated the necessary datum points. It all seemed to work fine, however, for some reason, I have come across the issue that my b-splines are not symmetrical along the z-axis (I have attached a screenshot). I was wondering if there is any easy fix for this.
Thank you in advance
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- Veteran
- Posts: 5513
- Joined: Thu Apr 05, 2018 1:53 am
Re: Constrain a point in a b-spline.
I think this would move the object so it's center of mass is on the origin.
Select the object, press Ctrl+Shift+P. In the python console enter:
If CenterOfMass doesn't work try CenterOfGravity.
Select the object, press Ctrl+Shift+P. In the python console enter:
Code: Select all
obj.Placement.translate(obj.Shape.CenterOfMass *-1)
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- Posts: 3
- Joined: Sun Jan 23, 2022 5:34 pm
Re: Constrain a point in a b-spline.
Unfortunately, doesn't seem to be doing anything for me. Neither does .
Code: Select all
obj.Placement.translate(obj.Shape.CenterOfMass *-1)
Code: Select all
obj.Placement.translate(obj.Shape.CenterOfGravity *-1)
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- Veteran
- Posts: 5513
- Joined: Thu Apr 05, 2018 1:53 am
Re: Constrain a point in a b-spline.
Install MeshRemodel workbench. There is a tool there that can be used to make a bspline though selected points. It actually creates a Draft bspline.
- Attachments
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- Snip macro screenshot-c24418.png (53.57 KiB) Viewed 1715 times
- thomas-neemann
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Re: Constrain a point in a b-spline.
I don't know if it's a solution for you, it's not a b-spline either, but it's in the sketcher.codeborg00 wrote: ↑Sun Jan 23, 2022 5:57 pm ...I was wondering if anybody has a solution to my problem.
...
https://www.youtube.com/watch?v=M7JkL6sAuA0
OS: Ubuntu 20.04.1 LTS (XFCE/xubuntu)
Word size of FreeCAD: 64-bit
Version: 0.20.27078 (Git) AppImage
Build type: Release
Branch: (HEAD detached at bcdd926)
Hash: bcdd926686f2245fe60baface1cce1ab3dff7a5b
Python version: 3.9.9
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.3
Locale: German/Germany (de_DE)
- thomas-neemann
- Veteran
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- Joined: Wed Jan 22, 2020 6:03 pm
- Location: Osnabrück DE 🇩🇪
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Re: Constrain a point in a b-spline.
here is another suggestion, with symmetrical, closed bsplinescodeborg00 wrote: ↑Sun Jan 23, 2022 5:57 pm ... I was wondering if anybody has a solution to my problem.
...
https://forum.freecadweb.org/viewtopic. ... 49#p566949