Import Datum entities into A2+

Discussion about the development of the Assembly workbench.
toralf
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Import Datum entities into A2+

Postby toralf » Fri May 17, 2019 5:13 pm

Is it possible to Import Datum entities (e.g. points, lines, planes, coordinate systems) with a body into A2+?
I ran several times into the topo naming problem. I would hope if the Datum entities would be imported they could be used for the A2+ constrains and would solve most of these problems.
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roerich_64
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Re: Import Datum entities into A2+

Postby roerich_64 » Fri May 17, 2019 7:11 pm

I bind my parts in the modules to master bodies and bind the master bodies together in the master_asm draft...
toralf
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Re: Import Datum entities into A2+

Postby toralf » Fri May 17, 2019 9:01 pm

Thanks for the reply.
Could you please explain this a little more detailed? Or can I read about this somewhere?
Do you have an example file?
toralf
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Re: Import Datum entities into A2+

Postby toralf » Fri May 17, 2019 10:11 pm

Dear Walter,

Thanks, I read most of it.
As far as I understand, you are not using the A2+ constrains but absolut placements to position the parts, correct?
The workflow you use is mainly to reduce the amount of data to be visualized by showing in most cases only the master shape.
But I do not understand how this solves the toponaming issues when constrains are used?
I my assemblies I need to constrain the parts with differnt parts at a lot of locations. Thus, I assume I will not be able to use a single master part for e.g. the housing. Specially not if I would like to have parts contrained to holes in the housing.

In a nutshell, I'm (and oviously several others on this forum) looking for a way to assemble complex assemblies by constrains and do not run into the topo naming issue when modifying the individual parts later in the process when automatically updating the contrains.
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easyw-fc
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Re: Import Datum entities into A2+

Postby easyw-fc » Fri May 17, 2019 10:23 pm

toralf wrote:
Fri May 17, 2019 5:13 pm
Is it possible to Import Datum entities (e.g. points, lines, planes, coordinate systems) with a body into A2+?
I ran several times into the topo naming problem. I would hope if the Datum entities would be imported they could be used for the A2+ constrains and would solve most of these problems.
ATM there is not a way to use Datum Planes or even Local Coordinate Systems...
There is still some work in progress to obtain a more robust A2p system...
enhancement: allowing LCS import and constraints: issue #237
create LCS-container under a2p_part
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roerich_64
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Re: Import Datum entities into A2+

Postby roerich_64 » Sat May 18, 2019 12:18 am

Ok.

In mostly things i have built with a2plus there are statik not dynamik parts.

I do not know what you will build.
But for now when you take the modules in his master bodys and attach them later together in a master assembly then the most problems with topo naming shoudt have a workaround for now...

What comes in the future i can not say... But i think Klaus (@kbwbe) could tell us more ;-)
toralf
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Re: Import Datum entities into A2+

Postby toralf » Sat May 18, 2019 5:55 am

easyw-fc wrote:
Fri May 17, 2019 10:23 pm
ATM there is not a way to use Datum Planes or even Local Coordinate Systems...
There is still some work in progress to obtain a more robust A2p system...
enhancement: allowing LCS import and constraints: issue #237
create LCS-container under a2p_part
Your request points in the same direction. Thanks for letting me know.
I’m not good at python yet, so I have trouble reading the code.
But it seams hat Klaus has done the code to import the LCS.
What still needs to be done?
kbwbe
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Re: Import Datum entities into A2+

Postby kbwbe » Sat May 18, 2019 4:13 pm

toralf wrote:
Sat May 18, 2019 5:55 am
But it seams hat Klaus has done the code to import the LCS.
What still needs to be done?
Hi,
not really much work regarding use of LCS has been done. The implemented code for importing LCS's is more a test than something else. For sure it will be usefull to import LCS' as reference data as doing so will overcome the topological naming issue.

In principal there are to possible ways to use them:
- making an additional "LCS-snap-together" solver for some kind of pseudo assembly
- modifiying the existing solver and enabling it to work with LCS' as references

A lot of things are not implemented now.
- consistent naming scheme for the LCS', to be robust against updates
- a new sort of LCS constraints
- selecting code for parts of the LCS' for feeding the solver
- missing solver adaptions

So this will not come soon. (Except there would help some coworkers to help with this topic)
toralf wrote: I ran several times into the topo naming problem. I would hope if the Datum entities would be imported they could be used for the A2+ constrains and would solve most of these problems.
At moment you can activate the preference "use experimental topological naming" of A2p. It has to be active from the very first beginning of an assembly. It avoids about 80% of the topological naming issues, but not all (and i think there are some small bugs left). Some knowledge is needed how to avoid problems.

I hope that FC will provide topological naming for future.
KBWBE

https://github.com/kbwbe/A2plus
latest release: v0.4.21, installable via FreeCAD's addon manager
Tutorials:
Paul Randall: https://youtu.be/mnkecA9S7kc
anisim (deutsch): https://www.youtube.com/watch?v=vDcaFq6IEJM
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easyw-fc
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Re: Import Datum entities into A2+

Postby easyw-fc » Sat May 18, 2019 4:23 pm

toralf wrote:
Sat May 18, 2019 5:55 am
But it seams hat Klaus has done the code to import the LCS.
What still needs to be done?
ATM this is a WIP...
It would be room to add Datum Planes also...
Here a file with an A2p object with a sub-container for Datum objects...
If you move the main object, the datum objs inside will follow...
The next step would be to allow constrains for these datum items.
A2p-ext-Datum.FCStd
(8.75 KiB) Downloaded 1 time
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moving-A2p-Datum.gif
moving-A2p-Datum.gif (563.01 KiB) Viewed 91 times
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kbwbe wrote:
Sat May 18, 2019 4:13 pm
A lot of things are not implemented now.
@Klaus, it would be nice to test the addition of a Datum Plane... this item is much similar to a Face, so probably it would be much easier to add constraints to this kind of item compared to LCSs.
As an alternative, the Datum Plane could be imported as a Plane (as I simulated in my attached file)...
What do you think?
Maurice