How to use main axes or datums as direction for applied forces

About the development of the FEM module/workbench.

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uwestoehr
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How to use main axes or datums as direction for applied forces

Postby uwestoehr » Thu Jul 18, 2019 12:28 pm

When setting the direction of a force I am not able to tell FC that it should use one if the main axes or a datum line. I assume I only use a wring setting.

Here is an example:
FreeCAD_3kDh1HPbkX.png
screenshot
FreeCAD_3kDh1HPbkX.png (29.62 KiB) Viewed 250 times

The force should act along the datum line. How do I achieve this? In the constraint dialog the datum line is not recognized.
Jee-Bee
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Re: How to use main axes or datums as direction for applied forces

Postby Jee-Bee » Thu Jul 18, 2019 1:49 pm

I asked this before see https://forum.freecadweb.org/viewtopic. ... hilit=axis

At that time there was not enough interest or need to fix it. New request new possebilities...
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bernd
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Re: How to use main axes or datums as direction for applied forces

Postby bernd » Thu Jul 18, 2019 7:10 pm

best to make a feature request on mantis and link to the two topics. Force contraint gui was done in C++. Means this is not done just in 10 minutes for me. Therefor chances are very small that I will try to add this. But if it is on mantis may be some other is more interested and will give it a try.

bernd
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bernd
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Re: How to use main axes or datums as direction for applied forces

Postby bernd » Thu Jul 18, 2019 7:12 pm

is it just not recognised by the force gui or does the property nit wor with this planes at all. Try to set it with property editor!
Jee-Bee
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Re: How to use main axes or datums as direction for applied forces

Postby Jee-Bee » Thu Jul 18, 2019 7:58 pm

Not recognized by gui

i added a easy example you can try
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uwestoehr
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Re: How to use main axes or datums as direction for applied forces

Postby uwestoehr » Thu Jul 18, 2019 10:30 pm

Jee-Bee wrote:
Thu Jul 18, 2019 7:58 pm
Not recognized by gui
Yes. I can e.g. as workaround draw a line along a main axis or datum line to get the direction I need but it would speed it up a lot if the FEM dialogs would recognize these elements as source for a direction.
bernd wrote:
Thu Jul 18, 2019 7:10 pm
best to make a feature request
I opened now issue #4064.
Jee-Bee
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Re: How to use main axes or datums as direction for applied forces

Postby Jee-Bee » Fri Jul 19, 2019 5:03 am

The request you created is mainly about the direction parallel to the selected axis(that's what i read at least).
Would it be possible to extend the request to add planes too? But when selecting a plane the the force direction is normal to/ perpendicular to the plane...
chrisb
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Re: How to use main axes or datums as direction for applied forces

Postby chrisb » Fri Jul 19, 2019 10:22 am

Jee-Bee wrote:
Fri Jul 19, 2019 5:03 am
when selecting a plane the the force direction is normal to/ perpendicular to the plane
+1
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uwestoehr
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Re: How to use main axes or datums as direction for applied forces

Postby uwestoehr » Fri Jul 19, 2019 11:06 am

Jee-Bee wrote:
Fri Jul 19, 2019 5:03 am
The request you created is mainly about the direction parallel to the selected axis(that's what i read at least).
Would it be possible to extend the request to add planes too? But when selecting a plane the the force direction is normal to/ perpendicular to the plane...
This is a very useful proposal I fully support!
However, from the technical point of view this has to be implemented differently I guess (an axis(line has a direction that is immediately accessible while the normal of a plane has to be calculated). Therefore I propose that you open another feature request (where you can refer to the one I created if you like).
chrisb
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Re: How to use main axes or datums as direction for applied forces

Postby chrisb » Fri Jul 19, 2019 11:39 am

bernd wrote:
Thu Jul 18, 2019 7:12 pm
ping
Do you prefer one or two tickets?