non uniform distributed load

About the development of the FEM module/workbench.

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UR_
Posts: 1348
Joined: Tue Jan 03, 2017 8:42 pm

Re: non uniform distributed load

Post by UR_ »

You are right, i noticed this too.
I think major waste of time is object adding (to tree).
I will have a look at curveWB, perhaps i can find the place where Chris_G does the magic. :roll:
Chris_G wrote:ping
@Chris_G, can we please have a hint from Premier League :?
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Chris_G
Posts: 1880
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Location: France
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Re: non uniform distributed load

Post by Chris_G »

UR_ wrote: Wed May 02, 2018 7:45 pm I think major waste of time is object adding (to tree).
Hi,
you will probably get much faster rendering by adding directly your stuff in the coin SceneGraph().
Here is an example :

Code: Select all

import FreeCAD
from FreeCAD import Vector
import Part
from pivy import coin

NUM = 10

# create a sample curve

poles0 = [Vector (-2.207077980041504, -0.4698541462421417, 0.0), Vector (-1.3755598068237305, 1.137541651725769, 0.0), Vector (0.10200775414705276, 1.2364583015441895, 0.0), Vector (1.397197961807251, -0.0834609717130661, 0.0)]
weights0 = [1.0, 1.0, 1.0, 1.0]
knots0 = [0.0, 1.0]
mults0 = [4L, 4L]
periodic0 = False
degree0 = 3
rational0 = False
bs0 = Part.BSplineCurve()
bs0.buildFromPolesMultsKnots(poles0, mults0, knots0, periodic0, degree0)
obj0 = FreeCAD.ActiveDocument.addObject("Part::Spline","BSplineCurve0")
edge = bs0.toShape()
obj0.Shape = edge

# compute sample points

parameters = [float(i)/NUM for i in range(NUM+1)]
poc = [edge.valueAt(p) for p in parameters] # poc = points on curve
nor = [edge.valueAt(p)+edge.normalAt(p) for p in parameters] # nor = normals

# here is the coin stuff

coinVec = list()
indexes = list()
for i in range(NUM+1):
	coinVec.append(coin.SbVec3f(poc[i].x,poc[i].y,poc[i].z))
	coinVec.append(coin.SbVec3f(nor[i].x,nor[i].y,nor[i].z))
	indexes.extend([i*2,1+i*2,-1])

# indexes = [0, 1, -1, 2, 3, -1, 4, 5, -1, 6, 7, -1, 8, 9, -1, 10, 11, -1, 12, 13, -1, 14, 15, -1, 16, 17, -1, 18, 19, -1, 20, 21, -1]
# the -1 index value is a break in the polyline

node = coin.SoSeparator()
pts = coin.SoCoordinate3()
lineset = coin.SoIndexedLineSet()
node.addChild(pts)
node.addChild(lineset)

pts.point.setValues(0,len(coinVec),coinVec)
lineset.coordIndex.setValues(0,len(indexes),indexes)

sg = FreeCADGui.ActiveDocument.ActiveView.getSceneGraph()
sg.addChild(node)
#sg.removeChild(node)

And here are my 2 favorite links about coin :
https://grey.colorado.edu/coin3d/annotated.html
http://www-evasion.imag.fr/Membres/Fran ... index.html
UR_
Posts: 1348
Joined: Tue Jan 03, 2017 8:42 pm

Re: non uniform distributed load

Post by UR_ »

Chris_G wrote: Wed May 02, 2018 9:26 pm Here is an example
Thanks!
Will have a look at this.
Thank you very much!
UR_
Posts: 1348
Joined: Tue Jan 03, 2017 8:42 pm

Re: non uniform distributed load

Post by UR_ »

[/quote]
thschrader wrote: Wed May 02, 2018 5:52 pm Is there a possibility to speed this up?
Now it's a little bit faster.
So no more coffee breakes! :lol:

ApplyNonUniformLoad.FCMacro
(7.84 KiB) Downloaded 59 times

hardcoded user input is presetted for example file from here:


https://forum.freecadweb.org/posting.ph ... 8#pr231275


@thschrader: Please don't overshoot :lol:
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thschrader
Posts: 2364
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Location: Germany

Re: non uniform distributed load

Post by thschrader »

UR_ wrote: Sun May 06, 2018 5:21 pm @thschrader: Please don't overshoot :lol:
no problem... :)
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Taufeeq2
Posts: 18
Joined: Fri Mar 30, 2018 12:39 pm

Re: non uniform distributed load

Post by Taufeeq2 »

there is a routine here http://web.mit.edu/calculix_v2.7/Calcul ... de190.html
But i dont know how to incoporate it in freecad
Jee-Bee
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Location: Netherlands

Re: non uniform distributed load

Post by Jee-Bee »

*DLOAD is the presure constraint in FreeCAD. only when applaying non uniform distributed load load you have to use the script somwhere in this topic
thschrader
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Location: Germany

Re: non uniform distributed load

Post by thschrader »

UR_ wrote: Sun May 06, 2018 5:21 pm Now it's a little bit faster.
So no more coffee breakes! :lol:
Yep. Writing the load needs only seconds. Very nice!
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Pep
Posts: 3
Joined: Fri Sep 20, 2019 12:12 pm

Re: non uniform distributed load

Post by Pep »

Hey everyone,

I was trying to use this, since it would be extremely useful to me. However, when I run it, it computes as if there is no load distribution. The report contains the following errors:

...
Pressure on shell mesh at the moment only supported for meshes with appropriate group data.
...
PySide2.QtCore.QProcess.ProcessState.NotRunning
PySide2.QtCore.QRegExp('\*ERROR.*\n\n', 1, 0)
...

with only the first one being red. Anyone knows what is going wrong here?
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bernd
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Location: Zürich, Switzerland

Re: non uniform distributed load

Post by bernd »

would you send the file you tested with, a link to the code you used and you freecad version info. than we could try to reproduce your problem
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