Import, Test, and Simulate FMUs in Simulink

Use FMUs to integrate heterogeneous components and create large-scale models in Simulink. Use the FMU Import block to import FMUs into your model. For more information on creating these large-scale models, see Choose Tools to Integrate Existing Components and MATLAB, C/C++, or Python Code into Simulink.

For large-scale system design, you can include FMUs in architecture models with System Composer. In System Composer, you can integrate FMUs into complex architectures and include FMUs in system-level analysis and traceability. For more information, see Linking to Existing FMU Files.

Use FMU with Simulink Test to observe internal variables, which allows you to access and verify internal FMU variables during simulation. Test and validate your FMU using wireless visibility into the internal states and signals of the imported FMU. For more information, see Observe Internal Variables of an FMU (Simulink Test).

Support for the FMUState feature allows you to save, restore, and manipulate FMU states during simulation. This setting enables testing, parametric analysis, and iterative development, with a high degree of flexibility and control over simulation workflows. You can use model operating points to stop and restart simulation at desired points and step back during simulation. For more information, see Capture Simulation State, Fast Restart, and Step Through Model Containing FMU.

You can debug your FMU that contains source code using an external debugger with Simulink. Use this option to set breakpoints, step through FMU source code during simulation, and identify issues at the implementation level. For more information, see Debug FMU with Source Code Using External Debugger.

You can execute your FMU in a separate process from the Simulink process. This option improves simulation performance and isolation, allows you to isolate FMU execution from the main Simulink process, and facilitates fault tolerance during simulation. You can enable this feature using the DebugExecutionForFMUViaOutOfProcess model configuration parameter. For more information, see FMU Import blocks.

You can generate an FMU for use in real time testing, making it possible to deploy models to hardware-in-the-loop (HIL) or other real-time platforms. When you use this option, the generated FMUs are suitable for applications with strict timing and reliability requirements encountered in embedded systems development. For more information, see Apply Functional Mock-up Units by Using Simulink Real-Time.

You can compile new FMU binaries from the FMU source code directly within Simulink for cases where modifications or platform-specific builds are required. This option enables you to customize and adapt FMUs for different simulation or deployment targets. For more information, see fmudialog.compileFMUSources.

Simulink supports multicore simulation of co-simulation components. You can run multiple FMUs or co-simulation units in parallel, making efficient use of multicore processors and reducing overall simulation time for large models. For more information, see Run Co-Simulation Components on Multiple Cores.

Simulink automatically performs numeric compensation for co-simulation to address numerical discrepancies and stability challenges that can arise during co-simulation. When integrating FMUs from diverse sources or with differing numerical properties, numerical compensation helps to create accurate and reliable results. For more information, see Numerical Compensation.

You can perform cross-platform simulation of your FMU that contains Linux binary on Windows using the cross-platform simulation feature enabled by Windows Subsystem for Linux. For more information, see Simulate FMU with Linux Binary on Windows.