Archived OpenModelica forums. Posting is disabled.

Alternative forums include GitHub discussions or StackOverflow (make sure to read the Stack Overflow rules; you need to have well-formed questions)


Forgot password? | Forgot username? | Register

Closed loops in MultiBody library not working

Closed loops in MultiBody library not working

Hi everyone,

I'm new to OpenModelica (and Modelica in general), I knew about it for a while, but finally I have decided to try it as a multibody simulation tool, mostly for teaching purposes. Thanks for the hard work, OM seems to be promising, overall, I really like the environment and look forward to use it much more in the future.

However I've found some problems, while most examples seem to work, when trying some standard examples with closed loops present the multibody library, specifically FourBar1 and FourBar2, they fail at different stages.

Specifically, FourBar2 fails to compute an initial state, and exits after using ~150mb ram, returning nan in most variables.

FourBar1 does not need to compute an inital state, but instead keeps on running for a long while (an hour so far) without any visible output.

Is there anything I am missing, or closed loops are not yet supported in OpenModellica (I read somewhere that support for the MB part is brand new in OM).

Cheers, Fran.

Re: Closed loops in MultiBody library not working

FYI, I am using the openmodelica-ubuntu packages, version 7574, downloaded some days ago, in Ubuntu Maverick amd64.

Re: Closed loops in MultiBody library not working

I'm a bit unsure of the status of all simulations as I don't work on the backend of OpenModelica, but you can check the last update from Jens, which suggests that indeed no examples with closed loops simulate with correct results yet:
https://www.openmodelica.org/svn/OpenMo … e/Makefile

User: anonymous
Password: none (4 letters)

Re: Closed loops in MultiBody library not working

I see, thanks for the info, I'll wait then until the multibody support improves a bit.

Regards.

There are 0 guests and 0 other users also viewing this topic
You are here: