Published: 2016-09-09 12:09   Updated: 2016-12-02 01:12

Simulation in a heterogeneous world

How the Functional Mock-up Interface enables greater understanding of system behavior early in the design cycle

Most of us know by now that there is not one single software tool that will solve all our simulation needs. Even if we narrow it down to system simulation, we will not find that One tool.

Not so long ago, handling different aspects of product design with separate tools was not a major problem.  But as competitive pressure builds to get products to market faster, the game is changing.

A major key to success is being able to integrate subsystems into system simulations early in the design process. This enables organizations to understand and assess system behavior, as opposed to component or subsystem behavior, to avoid flaws that become costly to correct in later stages.

FMI for interoperability

Tool interoperability -- the ability to connect different tools in coupled simulations -- is critical for understanding system behavior.

A customer in the automation business recently told me this: “We don’t consider a particular platform to be our major integration platform. Different aspects of the design process call for different solutions, where tools like CarMaker, Dymola and MATLAB/Simulink all serve as means to integrate simulation tools in different stages of our design process." Instead of a single product, the solution to the interoperability challenge is the Functional Mock-up Interface (FMI).

FMI is an open standard for exchanging portable simulation models. Models adhering to the standard are called Functional Mock-up Units (FMUs), which are like the DLLs of system simulation.

While the standard does not provide any software per se, it does deliver a standardized format for simulation models that is agnostic to what tool is generating and importing the FMUs. FMUs can be composed into aggregated system simulation models, or they can be imported and simulated in native environments. Released in 2010, FMI has quickly established itself as a major standard in system simulation and is now supported by more than 50 tools.

An FMI leader

Modelon was one of the early adopters of FMI and is today one of the leaders in the FMI community, actively contributing to development of the standard.

Modelon’s FMI solutions are based on best-in-class simulation tools, including CarMaker, Dymola and TestWeaver, and we provide products for bringing FMUs into established platforms such as MATLAB/Simulink and MS Excel. Applications range from Design of Experiments (DOE) to assess the effects of different components on system performance, to Hardware in the Loop Simulation (HILS) to verify the correct functioning of Electronic Control Units (ECUs) prior to field testing.

Modelon also contributes to the FMI open source community through the FMI Library (which is the foundation of the official FMU compliance checker), PyFMI and JModelica.org projects.

Perhaps most importantly, we help customers understand how FMI can facilitate and speed up their everyday design workflows, and we support them in getting started with the technology.

Interested in FMI? Get in touch!

Further reading:

  1. Blochwitz, T., et al.,  Functional Mockup Interface 2.0: The Standard for Tool independent Exchange of Simulation Models, Proceedings of the 9th International Modelica Conference, September 3-5, 2012, Munich, Germany, pp. 173-184.
  2. Åkesson, J., et al., Generation of Sparse Jacobians for the Function Mock-Up Interface 2.0, Proceedings of the 9th International Modelica Conference, September 3-5, 2012, Munich, Germany, pp. 185-196.
  3. Drenth, E., et al., Consistent Simulation Environment with FMI based Tool Chain, Proceedings of the 10th International Modelica Conference, March 10-12, 2014, Lund; Sweden, pp. 1277-1238.

 


Johan Åkesson holds a PhD in Automatic Control and a MSc in Computer Science, both from Lund University. Johan's specialties include compilers, numerical algorithms for simulation and optimization, FMI and Modelica. He currently leads Modelon's tool development team and he has also contributed to the development of the FMI standard.

 

by Johan Åkesson