Assembly 4 workbench

Discussion about the development of the Assembly workbench.
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Brutha
Posts: 221
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Re: A thought on terminology

Post by Brutha »

Zolko wrote: Mon Mar 07, 2022 1:07 pm
a coordinate system is a precise mathematical construct, we should not rename it. But you're right that "linking" them is probably not the correct terminology. What about "connecting local coordinate systems (LCS)" ? Would that be easier to understand ?

The Assembly4 documentation is now quite outdated, if you have proposals to improve would be helpful.
Well, I think the thing that stopped me understanding it was really the idea of "matching/linking/connecting local co-ordinate systems" rather than the linking/matching terminology.

As I user, I know I want to connect e.g. THIS point on an axle to THAT point on a wheel. The fact that this is achieved in Assembly4 by matching local coordinate systems is not necessarily something the user needs to worry about I think - in my case it was a positive hindrance.

Anyway, was just a thought!
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mnesarco
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Re: Assembly 4 workbench

Post by mnesarco »

I think it is hard to find a better name than Local Coordinates System. It is very precise. It defines a point in space and orientation in 3 axes. Oriented position in 3D is very complex (6DOF). Once you understand what LCS is, it is very straight forward to work in ASM4. I think it is better to improve the documentation. This is my personal point of view of course.
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onekk
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Re: Assembly 4 workbench

Post by onekk »

mnesarco wrote: Tue Mar 08, 2022 12:20 am I think it is better to improve the documentation. This is my personal point of view of course.
Making or improving documentation is always better than coding alone, as if you are a developers it is "natural to think" that "always is clear and plain" but you are "biased" as you "know what you are doing".

Not surprisingly other people could have different point of view. It is hard I know, but something, taking some step backward and see the thing from another point of view will help a lot.

This is what an artist do when making maybe a big sculture, after having concentrated many days on a details, he had made the best he can.

Then he made some steps backward and see that the detail is too big for the whole sculpture, or the sculpture is not matching with other things.

So Michelangelo has rotate by 45 degree the whole Moses and this has been a lot of work, and this fact is visible, other fact is that he has used a "bad translation" of the ebraic term of "keter" (crown) into "keren" (horns) as some literate has translated in his era, so he has made two "horns" on Moses head (no assumptions on Moses Wife fidelity) :D

https://www.michelangelo.org/moses.jsp

Sorry for the OT

Regards

Carlo D.
GitHub page: https://github.com/onekk/freecad-doc.
- In deep articles on FreeCAD.
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aapo
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Re: A thought on terminology

Post by aapo »

Zolko wrote: Mon Mar 07, 2022 1:07 pm a coordinate system is a precise mathematical construct, we should not rename it. But you're right that "linking" them is probably not the correct terminology. What about "connecting local coordinate systems (LCS)" ? Would that be easier to understand ?
I think it would also be possible to simply say that Assembly 4 uses LCS as connectors. E.g., "Assembly 4 Workbench uses a specific datum object type, local coordinate systems (LCS), as connectors for placing the parts. The workbench assembles parts by automatically moving two parts together by making sure that two LCS connectors, one in each part, are made to be exactly coincident. By creating one or more LCS connectors within each part, and selecting desired connections between the parts by linking these LCS connectors with Assembly 4 provided tools, the user can create a chain of interlinked parts, which is the final assembly. Usually, the user starts by linking and connecting the LCS connector in the first part to the assembly's special Origin LCS connector, which can be found in the root of the assembly."
Outsourced
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Re: Assembly 4 workbench

Post by Outsourced »

Hello Again FC Care of Assembly4,
OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 2022.111.30764 (Git)
Build type: Release
Branch: LinkDaily
Hash: ef3092bcbca5475eff4eb7ff7933eb3e9bbbe4b9
Python version: 3.8.6+
Qt version: 5.15.2
Coin version: 4.0.1
OCC version: 7.6.0
Locale: English/Australia (en_AU)

Firstly thankyou for the program & the time and effort thus far I am incredibly grateful -post SCI its given more than you will ever know, & this communication however is probably going to irritate an old wound but doing so as in the hope to understand if this problem(s) has a work around(s).
Please View
https://youtu.be/l9S_yT-YEGQ

File: https://drive.google.com/drive/folders/ ... sp=sharing

So ...... There is geometric instability but that's not the problem. I've used every trick I know to get this str8 line mechanism thus far.

IE. 1 Separation of Construction & Dynamic Sketches. All Lines are constrained with a 0.001mm gap. the final ' L' - Short Link is Reversing pad or changing planes or spinning on its axis. I thought I'd beaten this issue via padding a shape bind of the sketch. But nope????

How do I tell how its failing? And How do I resolve for those scenarios?

Cheers
Hyme
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Zolko
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Re: Assembly 4 workbench

Post by Zolko »

Outsourced wrote: Mon Mar 28, 2022 3:24 am How do I tell how its failing? And How do I resolve for those scenarios?
looks like a classical toponaming issue. I can't download the file to investigate, it asks for a google account
try the Assembly4 workbench for FreCAD — tutorials here and here
Haavard
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Re: Assembly 4 workbench

Post by Haavard »

Hi everyone

I recently created two assemblies using Asm4, and ran into some small issues.
Because of the number of LCSs, parts, bodies, links and fasteners, i created folders/groups for each, to quickly be able to toggle visibility, and to organize the model tree. However:

[*] The hide/show LCS buttons did not work for objects in folders, so i created a PR for this.

[*] Only attributes from objects either directly under the Assembly model, or in a part container, would be saved in configurations. That meant i could not hide all objects in a group (all fasteners for example) and save that as a configuration. This is fixed in this PR.

[*] Last one is just a cosmetical one, but the first column in configuration spreadsheets is too narrow, so you have to manually widen this column to be able to see the full name of the objects. This is kind of annoying when jumping between multiple configuration spreadsheets because the column jumps back and forth. This PR sets the default width for new configuration spreadsheets fairly wide, so most objectNames should be fully visible.
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Zolko
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Re: Assembly 4 workbench

Post by Zolko »

Haavard wrote: Mon Apr 18, 2022 10:19 pm Hi everyone
...
thanx for the fixes, they're included in a new version released today (v0.11.11)
try the Assembly4 workbench for FreCAD — tutorials here and here
mcdanlj
Posts: 68
Joined: Sun Dec 01, 2019 12:10 am

Requesting critique on a sample assembly

Post by mcdanlj »

I first tried Assemlby4 yesterday, so I'm quite new to this. Thanks for all your work on this workbench!

I'm still kind of feeling my way around after reading through the tutorials. I made a model of a keyway cutter tool, attempting top-down design as a single file. I definitely want it to be a single file (really, single directory in my use; I'm using the realthunder builds for save-as-directory) in this case. Within that constraint, I would love feedback on how I used Assembly4 to put this together.

I haven't yet renamed all the features on individual parts in this design, I'll probably do that later. I have not yet added any connecting hardware; I haven't even decided whether to do it the easy way or the right way. I know I did a few things the hard way in Part Design and would make it simpler if I started over. I'm looking here for feedback on the use of Assembly4, for example whether the way I set up my LCSs makes sense to those more skilled.
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hasecilu
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Re: Assembly 4 workbench

Post by hasecilu »

I found a problem with the BOM Part List Tool (BOM):
Assembly4 don't add parts that are inside a Group to the BOM, so, if you organize your Parts in Groups (folders) these Parts will not appear in the BOM, if we compare with the BOM of Fasteners, there is no problem if the fasteners are inside a Group.
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