FMU models

[Vincent Person]

Hello everybody, First of all thank you for this great job. Chrono is a very powerful tool. I am currently interested in the FMI standardized format. I read that in 2019 the team was thinking of integrating it in Chrono Project to be able to import or export FMU models in the future. Is there any progress on this subject or work under progress ?

If not, any help or advises on steps to follow if I would like to be able to do it ?

Thank you so much.

[Dario Mangoni]

Hi,
you come at almost the right time: in the next few weeks I'll start looking into some general/automatic way to export FMUs out of Chrono and I plan to be able to generate the first Cosimulation FMUs within September.
I recently spent some time upgrading and fixing the Chrono serialization feature that should come in handy for the FMU exporting process so it's one issue less.

However, I won't probably have time to deal with the ModelExchange version any time soon. Same applies for the most advanced features like fmi2GetDirectionalDerivative for which I don't have an immediate need.

In any case, please consider that I'm looking for a general/automatic process: it should be WAY easier if you just want to manually create an FMU for your specific code.
In this case you should start from downloading the FMI headers https://fmi-standard.org/ and create the definition for the functions that you find in FunctionTypes.h.
This approach is easier, but you still need to have some knowledge about the compilation and linking process, especially if you go for the runtime dynamic linking.

Hope to have better news soon.
Dario

[Vincent Person]

Hi,

Thank you very much for your quick reply.

On your side, do you already have tried to manually create a Cosimulation FMU ? Anything to share ? 

As you recommanded, to start I am going will try it on my side too.

Please keep me in touch !

Thanks a lot.

Vincent

[Dario Mangoni]

Hi Vincent,
I just really started last Saturday in some spare time so I don't have any specific suggestion to give you yet.
As you probably may want to do, I just set up CMake to work with some generic code without even linking Chrono, just rapidxml to generate the modelDescription.xml.
I started writing the definition of some function and not much more.
Anyway, I'm also thinking to give a look at the OpenModelica implementation to see if there is any useful hint.

Dario

[Vincent Person]

Ok thanks for the tips, 

I will keep you in touch on my side if I have some news to share.

See you in September for the mega update maybe :)

Thanks.

Vincent