topic Re: Inventor Nastran 2020 closes unexpectedly when sub-assembly is added in Inventor Nastran Forum

Inventor Nastran 2020 closes unexpectedly when sub-assembly is added

Roelof.Feijen — Fri, 27 Sep 2019 09:53:05 GMT

Hello,

I am running into an issue where Inventor and/or Nastran closes unexpectedly when sub-assemblies are used.

When I finally promote all parts from the sub-assemblies to the top assembly the software does not close unexpectedly. I tried to exclude everything and finally ended up with an empty assembly containing an empty sub-assembly that makes the software crash. Even when it is created from scratch.

Can someone please confirm if the steps shown in the screencast below is reproducible?

Re: Inventor Nastran 2020 closes unexpectedly when sub-assembly is added

John_Holtz — Fri, 27 Sep 2019 14:33:39 GMT

Hi Roelof,

I have confirmed that the steps in your video produce a crash.

Since your video is an empty assembly inside of an empty assembly, I am not too surprised that this is not supported. It is not too common to do an analysis on nothing. 😁 If I place a component in the second assembly, there is no crash when I enter the Nastran environment.

It sounds like you were suppressing the parts in the subassembly. I think that you should suppress the subassembly instead. Does that work on your computer? (It did work for me, even though the end results was an empty assembly.)

I will report this issue. Although an uncommon work flow, it should not crash the software.

Re: Inventor Nastran 2020 closes unexpectedly when sub-assembly is added

John_Holtz — Fri, 27 Sep 2019 15:04:34 GMT

Hi again.

I just found an indication that this has already been reported.

And I see the problem is a little different than I originally thought. If one part is suppressed in a subassembly but other parts are active, Inventor Nastran will crash! So I suspect that you were not suppressing all parts but only some parts. I did not understand that until just now. 🙄

Re: Inventor Nastran 2020 closes unexpectedly when sub-assembly is added

Roelof.Feijen — Fri, 27 Sep 2019 17:27:19 GMT

Hello John,

Thank you for your time and watching this strange process.

Normally I follow the following method with assemblies and sub-assemblies.
1. Create a Level of Detail in the top assembly
2. Set the selection method to Part selection
3. Select the parts you want to analyze
4. Invert the selection
5. Suppress the parts that you don't want to analyze

See this screencast.

I used this workflow in the 2017, 2018 and 2019 version. Yesterday I did that for the first time in the 2020 version. Then the software crashed.

I started investigating that and finally came up with an empty top assembly and an empty sub-assembly.

Glad to read that it is a known issue and I am not the only one.

Re: Inventor Nastran 2020 closes unexpectedly when sub-assembly is added

Roelof.Feijen — Mon, 21 Sep 2020 07:31:06 GMT

For anyone who finds this topic and has the same problem. This issue has now been resolved in 2020.2.