FMU export of system with embedded FMU does not work

[matthiasliermann]

I created a simple model which includes an FMU generated with the FMIKit.

I export this model as an FMU again without errors or warnings, but the generated nested FMU does not execute. In Simulink the error message is:

Failed to instantiate FMU. The FMU crashed (exception code: ACCESS_VIOLATION).
Error in 'untitled/FMU' while executing C MEX S-function 'sfun_fmurun', (mdlStart), at time 0.0.
Caused by:
Unexpected Standard exception from MEX file.
What() is:Failed to instantiate FMU. The FMU crashed (exception code: ACCESS_VIOLATION).
.. 

With the FMU Simulator the message is:
Could not lad shared library. The specified module could not be found. (System Error 126)

Attached is my example code.

• gain.slx: model containing a gain block (Matlab 2019b)
• gain.fmu : cosimulation FMI 2 FMU of a simple model containing a gain block
• integrator.slx: model containing a integrator block (Matlab 2019b)
• integrator.fmu : cosimulation FMI 2 FMU of a simple model containing a integrator block
• FMUinFMUtest.slx: model which contains the two FMUs
  FMUinFMUtest.zip

[matthiasliermann]

Hello, I looked at that closed issue, which looks similar than mine.
issue 186
Do you have any idea what I need to do to create nested FMUs? Does it work with everyone else?

[chrbertsch]

You seem to use rtwsfcnfmi.tlc target. To my understanding, nested FMUs are only supported with the grtfmi.tlc target

[matthiasliermann]

Thanks a lot! You are right. This is very helpful. Could you please help me to understand the underlying issue? I have generated my own FMU from c-code and can't get the nested sfunction to work with this one.

[t-sommer]

Nested FMUs are not supported with rtwsfcnfmi.tlc.

[matthiasliermann]

Thanks for the clarification. I understand that I can't use the sfunction FMI target. My goal is then to export an FMU with the grt fmi target of a system which includes a custom-made FMU. I made this FMU myself from scratch and would like to include in in a system which I want to export as an FMU with the FMIKit using the grt fmi target. Please point me in a direction what I need to do to get this to work. Thanks!

[t-sommer]

The only requirement for exporting nested FMUs with grtfmi.tlc is that they have binaries for the platform you're exporting for. There is no source code required.

[hemant6043]

I am using an FMU export from Adams model and trying to run it in simulink and I am still getting this error
Error in 'test/FMU' while executing C MEX S-function 'sfun_fmurun', (mdlStart), at time 0.0.
Caused by:
Unexpected Standard exception from MEX file.
What() is:Failed to instantiate FMU