Another approach to assembly solver (A2plus)

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kbwbe
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Re: Another approach to assembly solver (A2plus)

Post by kbwbe »

easyw-fc wrote:ping
manuelkrause wrote:ping
Hi Guy's,
thank you very much for your PR's. :D
Everything is merged to master branch.

Hi everyone:
There is a new release of A2plus now: V0.3.1

New features:
- direct import of step files
- new "centerOfMass" constraint. (join to faces by it's centers)
KBWBE

https://github.com/kbwbe/A2plus
latest release: v0.4.56, installable via FreeCAD's addon manager
Tutorial: gripper assembly https://www.youtube.com/watch?v=QMxcQ5tssWk
Documentation: https://www.freecadweb.org/wiki/A2plus_Workbench
herbk
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Re: Another approach to assembly solver (A2plus)

Post by herbk »

Hi Klaus,
kbwbe wrote: Wed Feb 06, 2019 9:32 pm - new "centerOfMass" constraint. (join to faces by it's centers)
would not be "centerOfFace" a the better name for it?
Gruß Herbert
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easyw-fc
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Re: Another approach to assembly solver (A2plus)

Post by easyw-fc »

herbk wrote: Wed Feb 06, 2019 9:47 pm Hi Klaus,
kbwbe wrote: Wed Feb 06, 2019 9:32 pm - new "centerOfMass" constraint. (join to faces by it's centers)
would not be "centerOfFace" a the better name for it?
hi @herbk
the constraint is based on center of mass... it could even be improved using closed edges as addition...
moreover think of a face with an asymmetric hole ... which is its center? the center of mass is the right candidate imo.
kbwbe
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Re: Another approach to assembly solver (A2plus)

Post by kbwbe »

herbk wrote: Wed Feb 06, 2019 9:47 pm Hi Klaus,
kbwbe wrote: Wed Feb 06, 2019 9:32 pm - new "centerOfMass" constraint. (join to faces by it's centers)
would not be "centerOfFace" a the better name for it?
Hi Herbert,
Hi Maurice,
i admit, the name is a little bit confusing for me too. Physically a face does not have a mass.
KBWBE

https://github.com/kbwbe/A2plus
latest release: v0.4.56, installable via FreeCAD's addon manager
Tutorial: gripper assembly https://www.youtube.com/watch?v=QMxcQ5tssWk
Documentation: https://www.freecadweb.org/wiki/A2plus_Workbench
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easyw-fc
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Re: Another approach to assembly solver (A2plus)

Post by easyw-fc »

I have used the OpenCascade function CenterOfMass for getting the center of mass of a face (this is a very precise function) ...

Code: Select all

dep1.refPoint = plane1.Faces[0].CenterOfMass
https://github.com/kbwbe/A2plus/pull/16 ... 9ff182R350
and here a sample of a face which has its 'center' moved because of holes...
face-centerofmass.png
face-centerofmass.png (70.37 KiB) Viewed 2056 times
face-centerofmass2.png
face-centerofmass2.png (79.91 KiB) Viewed 2054 times
kbwbe
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Re: Another approach to assembly solver (A2plus)

Post by kbwbe »

easyw-fc wrote: Wed Feb 06, 2019 10:22 pm I have used the OpenCascade function CenterOfMass for getting the center of mass of a face (this is a very precise function) ...

Code: Select all

dep1.refPoint = plane1.Faces[0].CenterOfMass
So i think we have to put some more description to the tooltip of the new constraint. Then it's name is IMHO ok.

P.S: I modified the tooltip on master and devel branch. Done.
KBWBE

https://github.com/kbwbe/A2plus
latest release: v0.4.56, installable via FreeCAD's addon manager
Tutorial: gripper assembly https://www.youtube.com/watch?v=QMxcQ5tssWk
Documentation: https://www.freecadweb.org/wiki/A2plus_Workbench
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Vincent B
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Re: Another approach to assembly solver (A2plus)

Post by Vincent B »

"create simple shape" seems not to carry out a solid. Could you check out that?
Something that not be a solid cannot become a consistent mesh for FEM.
thanks.
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Vincent B
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Re: Another approach to assembly solver (A2plus)

Post by Vincent B »

easyw-fc wrote: Tue Feb 05, 2019 11:43 pm You need to create a new file saved i.e. as 'Assy1' and then import your 'SizeNotFollow' file as an a2p part inside it. This will create a link object to your original file.
ok, but if several parts are handled with a spreadsheet, how can do?
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easyw-fc
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Re: Another approach to assembly solver (A2plus)

Post by easyw-fc »

GlouGlou wrote: Fri Feb 08, 2019 5:53 pm "create simple shape" seems not to carry out a solid. Could you check out that?
Something that not be a solid cannot become a consistent mesh for FEM.
thanks.
this should be solved in this PR
you can play also with the A2p preference 'use solid union for importing parts and subassemblies (experimental)' to get all solid or just the solid of the shells.
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easyw-fc
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Re: Another approach to assembly solver (A2plus)

Post by easyw-fc »

easyw-fc wrote: Fri Feb 08, 2019 9:09 pm
GlouGlou wrote: Fri Feb 08, 2019 5:53 pm "create simple shape" seems not to carry out a solid. Could you check out that?
Something that not be a solid cannot become a consistent mesh for FEM.
thanks.
this should be solved in this PR
EDIT and with this commit
you can play also with the A2p preference 'use solid union for importing parts and subassemblies (experimental)' to get all solid or just the solid of the shells.
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