[Khamar & Edrisi] Matlab/OpenSim 3.3 Simulation running on Matlab/OpenSim 4.X

[Thomas Mokadim]

Hi the OpenSim DevTeam and Community !

I'm Thomas, a French PhD student working on lower exoskeleton. I would like to use the simulation made by Khamar and Edrisi (https://simtk.org/projects/simexo) a few years ago and work around it to fit my needs.

As the simulation running OpenSim - Matlab - Simulink was coded in 2016-17, OpenSim 3.3 was the latest release available. At that time, the use of MEX interfaces allowed Matlab and OpenSim to exchange data (process explained by Stanev's project and an other one ... ).
Since OpenSim 4.0, the new Matlab API allows a "native" communication to Matlab.

I am wondering about the compatibility of this old simulation project regarding a 2022 OpenSim. Should I get prepared to change everything in the code ? ( recoding it ?), or will it work kinda straight forward with minor modifications ?

Thank you for your help. If anyone managed to run this simulation on a 4.X OpenSim, please raise a hand
Regards,

Thomas

[Ayman Habib]

Hello,

The project link you pointed to doesn't give much details about what was done in mex files. As a general guideline for users migrating from earlier releases to 4.0+. If the code creates custom components (Forces, muscles, controllers etc.) then expect a major refactoring or rewrite as the interfaces to define/aggregate a model changed significantly in the 4.0+ codebase. If the code is only using the "tools" and "analyses" that operate on models then the change will be minimal and you maybe able to simplify the code further. I don't think there's much more granularity that we can provide. Please contact the project developers for more info or to see if they have a more recent/upgraded implementation. Let us know if you have more specific questions.

Best regards,
-Ayman