Use sketch for kinematic

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kisolre
Posts: 1361
Joined: Wed Nov 21, 2018 1:13 pm

Re: Use sketch for kinematic

Postby kisolre » Sat Oct 12, 2019 6:22 pm

Zolko wrote:
Sat Oct 12, 2019 5:44 pm
Isn't this similar to the assembly without solver thing ?
Assembly4 was not usable in regular builds before the Link Merge and I didn't need actual assembly in my designs so far so did not bother to test it. Now I have it installed from addon manager but did not actually test its capabilities - again because I dont really have the need.
Zolko wrote:
Sat Oct 12, 2019 5:44 pm
Does this approach also work if you want to re-use a part several times ?
Clones work well if I need several of the same part. And they can be moved around as happens here. Or basefeature if some minor tweaks are required. I recently used basefeature to some partdesign feature to have similar parts with same base geometry but different finishing features. This works without complaining because of the link merge.
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ppemawm
Posts: 561
Joined: Fri May 17, 2013 3:54 pm
Location: Manhattan New York

Re: Use sketch for kinematic

Postby ppemawm » Sat Oct 12, 2019 6:40 pm

kisolre wrote:
Sat Oct 12, 2019 5:11 pm
For the next part I again select meaningful origin and orientation, draw something in the first sketch so body will be visible and then move the second part to there it should be relative to the first and design it there.
This sounds alot like what I do (modelling in context) except I first locate the next Body origin at the proper interface in the (sub)assembly before creating the body. I think this is similar to Zolko's approach but without using the LCS feature.

I have not tried Assembly4, heck, I have not even learned how to use A2plus. I cannot yet see how this works with top down modelling. So far, the master sketch approach works quite well for me especially for articulating mechanisms.
"It is a poor workman who blames his tools..." ;)
kisolre
Posts: 1361
Joined: Wed Nov 21, 2018 1:13 pm

Re: Use sketch for kinematic

Postby kisolre » Sat Oct 12, 2019 8:39 pm

Final Excavator model. To manipulate rotate the PlatformSk sketch and move Slider bodies along their X axis. This was hard just to make a point :)
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Screenshot02.JPG
Screenshot02.JPG (120.67 KiB) Viewed 363 times
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And a video.
phpBB [video]


It is easy to break if you are not carefull with constraint values :)

OS: Windows 8.1 (6.3)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.18504 (Git)
Build type: Release
Branch: master
Hash: f66023a646db4b2502bb3637897443b3525ca3c7
Python version: 3.6.8
Qt version: 5.12.1
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: Bulgarian/Bulgaria (bg_BG)
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Excavator.FCStd
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