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PostPosted: September 18, 2020, 5:42 am 
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I have *just* started working seriously on a chassis design - including spending 3 weeks of evenings ramping myself up on Fusion 360 in order to do static stress analysis. I finally got to the point where I can load up my dummy chassis and measure the torsional stiffness as I'd like some confidence that I meet the Australian Design Rules before starting.

Now I get an email from Autodesk last night which says:
Quote:
Important changes are coming to your Fusion 360 for personal use software that you need to know about.

Effective October 1, 2020, functionality in Fusion 360 for personal use will be limited, and you’ll no longer have access to the following:

Probing, 3 + 2-axis milling (tool orientation), multi-axis milling, rapid moves, automatic tool changes
Multi-sheets, smart templates, output options for drawings (print only).
Download options from public share links
Cloud rendering
Export options including DWG, IGES, SAT, STEP, and DXF (Note: DXF can still be saved via sketch)
Simulation and generative design
Unlimited active and editable Fusion 360 documents (10 doc limit).
Fusion 360 extensions – Generative Design and Manufacturing Extensions
These changes are being made to allow us to scale, align intended usage with the various offerings, support advanced capabilities for Fusion 360 subscribers, and stay true to our guiding principles of democratizing design for everyone.

Fusion 360 for personal use is still free for those of you working on home-based, non-commercial design, manufacturing, and fabrication projects.

For more information about these changes, please refer here and the FAQ.


Most importantly to me, they're taking away Simulation, and they're taking away export to open formats. Having just started learning the damn thing and being that it was only last week that I first started getting valid-looking results, to say that I feel a bit betrayed and bait-and-switched would be an understatement. If you've got any models in Fusion, now is the time to export them to STEP files otherwise you will probably never get them into third-party tooling.

Question time: I now probably need a new FEA tool. What is everyone using to do their chassis stiffness simulations these days? Preferably something free and open that won't be yanked out from under me while I'm in the middle of my project.

Screenshot of my dummy-test-totally-not-real-and-with-bad-proportions chassis under simulation in Fusion follows...


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PostPosted: September 19, 2020, 8:35 am 
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Joined: July 29, 2006, 9:10 pm
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Location: Oregon, usually
Welcome, polyglot. I've approved your post, only one to go and you can approve your own posts.

Out of curiosity, why is your example a...
polyglot wrote:
Screenshot of my dummy-test-totally-not-real-and-with-bad-proportions chassis...
...rather than your Real Thing?

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Locost builder and adventurer, and owner/operator of http://www.kineticvehicles.com


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PostPosted: September 20, 2020, 8:00 am 
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Joined: July 23, 2020, 5:16 am
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JackMcCornack wrote:
Welcome, polyglot. I've approved your post, only one to go and you can approve your own posts.

Out of curiosity, why is your example a...
polyglot wrote:
Screenshot of my dummy-test-totally-not-real-and-with-bad-proportions chassis...
...rather than your Real Thing?


Fair question - I wanted a very simple structure just to test the workflow because my earlier attempts at drawing more-correct geometry resulted in lots of simulation problems (self-intersecting mesh, singularities, overlaps, etc). This was my first back-to-basics bunch-of-tubes that manages to give a valid answer. The important dimensions, tube sizes, etc, are all model parameters though, so it is easy to adjust - pic below is the same thing but with the numbers adjusted for comic effect.

Still keen to find any other FEA tools that people might be using, in order that I not drop $400-$1000 on CAD tools that I did not intend to...


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PostPosted: September 20, 2020, 2:51 pm 
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Joined: April 15, 2014, 1:54 pm
Posts: 470
Have you explored Grape FEA? Or do you need a program that does more modelling?


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PostPosted: September 21, 2020, 6:54 pm 
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I haven't tried Grape, no. Have people found that its results to be fairly accurate with respect to tubular chassis? How well does it represent local stresses around welds?


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PostPosted: September 21, 2020, 9:03 pm 
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Horizonjob did some work with Grape on the Car9 tube chassis.

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Cheers, Tom

My Car9 build: viewtopic.php?f=35&t=14613
"It's the construction of the car-the sheer lunacy and joy of making diverse parts come together and work as one-that counts."

Ultima Spyder, Northstar 4.0, Porsche G50/52


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PostPosted: September 25, 2020, 11:09 pm 
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As a Fusion 360 user I managed to analyse my chassis after much trial and error. I had to build an entirely new simplified chassis to get it to run without errors. viewtopic.php?f=36&t=20183

I am bummed by the new restrictions as of 10/1 but the I will probably still keep using it as my simulation is done.

Some who are looking for alternatives to Fusion suggest FreeCAD which will do FE. https://wiki.freecadweb.org/FEM_Module
However, I have not tried it so I cannot vouch for it.


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PostPosted: September 28, 2020, 12:13 pm 
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Joined: October 23, 2010, 2:40 am
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Received this email from the Fusion folks this morning:

"STEP export will remain available for Fusion 360 for personal use.This removal of STEP export was previously announced as part of the changes to curb misuse of Fusion 360 for personal use by commercial users. This change had unintended consequences for the hobbyist community.

For this reason, we have made the decision to continue to allow STEP export for personal, non-commercial users. It remains in product unchanged and will not be removed as other announced changes roll out this October and January.

We want you to know, while the changes to the personal use entitlement were necessary, we remain committed to our community. You will continue to see development and investment in Fusion 360 for personal use.

-The Fusion 360 Team"

_________________
Cheers, Tom

My Car9 build: viewtopic.php?f=35&t=14613
"It's the construction of the car-the sheer lunacy and joy of making diverse parts come together and work as one-that counts."

Ultima Spyder, Northstar 4.0, Porsche G50/52


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PostPosted: October 16, 2020, 1:00 am 
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Joined: July 23, 2020, 5:16 am
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I decided to suck it up and pay :( for a license while it's on discount during this transition.


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