The Functional Mock-up Interface (FMI) is an open standard for the exchange and co-simulation of dynamic models between different software tools. It defines a common interface for models packaged as Functional Mock-up Units (FMUs) - self-contained zip files that include model equations, data, and binaries. FMI enables seamless model sharing, tool interoperability, and consistent simulation workflows across development environments.

🌐  FMI Standard: https://fmi-standard.org/

Find some general information about FMI in the below wiki page.

Develop your self-awareness by following 🎓 FMI Tutorials.

Discover the 🐍 FMPy python package to handle FMUs.

Applications

FMIs applications are many:

• Exchange of physical models between engineering teams (can be black box, encrypted)
  • For system integration
  • For control law design
• Hardware-In-the-Loop (HIL) testing: the FMU can be recompiled on a specific target platform (HIL platform, raspberry pi...)
  • Training simulator
  • Verification & Validation
  • Virtual Commissioning
  • ...
• Communication bridge between software when doing co-simulation (the FMU can be acting purely as a communication box)
• ...

FMI 3.0

Dymola implements several new features of FMI 3.0, improving the usage fo FMUs, such as:

• Co-Simulation: introduces early return, event mode, intermediate update and variable step size communication
• Array variables: better handling of array signals and variable-size parameter arrays
• Input interpolation: smoothing of inputs (embedded in the FMU) allows the integrator to continue the simulation without any reset
• Source code FMU import
• Terminals and Icons: help the user to build consistent systems from FMUs and render the systems more intuitively with better representation of structured terminals (for instance busses and physical connectors) in a special XML file.

Model Exchange VS Co-Simulation

Model Exchange Equations of the model are exchanged without the solver which can be used by other simulation tools. When to consider Model Exchange? No special solvers required Online/ Offline Simulation Embedded control systems on microprocessors   Co-Simulation Equations of the model are exchanged with the solver. Data is exchanged and controlled by a master algorithm. When to consider Co-Simulation? Specific authoring tool solvers are required Decoupling of models Use of advanced master algorithms

Black-box FMU

When using "Only Black-Box" FMU option:

• modelDescription.xml: variables are concealed with generic naming
• unselect the option of internal result file generation, to prevent the real naming to be exposed in the created .mat
• for readability of generated code, make sure SourceCodeGeneration option is disabled
• for diagnostics in error messages, for example division by zero: will be ”concealed…” for encrypted libraries or set Advanced.Translation.RemoveDiagnosticMessages=true

FMI Coverage within Dassault Systemes