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System Structure and Parametrization (SSP) is a tool-independent standard used to define complete systems consisting of one or more Functional Mock-up Units (FMUs). The FMUs generated by various third-party suppliers can be exported from the modeling tool. The exported SSP file can then be imported to various simulation tools (such as Dymola), enhancing the interoperability. For systems without FMUs, SSP can still be used to export the internal system structure, providing a standardized way to share and reuse system architectures. SSP export works only on instances.


System structure in the SysML and Modelica.

Automatically simulating in Dymola

You can automatically simulate the SSP file in Dymola and export the CSV file to the Results Player in just one click. This method saves you the time and efforts of manually exporting the SSP file in the modeling tool, launching Dymola, Importing and simulating the SSP file, exporting the CSV file and importing the CSV file again into the Results Player.

Prerequisites

  • You must have the Windows Operating System.
  • You must integrate the Dymola application with your modeling tool with help of the Integrations dialog. To open Integrations dialog, click Tools> Integrations.
  • You must use the Dymola version 2024x or later.


To automatically export model data to SSP, simulate it in Dymola, and then load the results to the Results Player

  1. Right- click the FMUControl_FMUTank : RequirementsVerification> Simulation and from the contextual menu select the desired simulation configuration to be simulated in Dymola.



Once simulation is done, results are automatically loaded into the results player.

  • You can choose the solver in the project options, click Options> Project> General> Simulation> Dymola Engine. 
  • The timing properties required for the simulation are used from the simulation configuration.

Manually exporting the SSP file from the modeling tool

To export the SSP file

  1. In the Containment tree, right-click the instance, and select the Export to SSP command.



  2. In the Select Destination Directory, select the location to save the SSP file.

Manually importing and simulating the SSP file in the Dymola


To import the SSP file in Dymola
  1. Click File>Open>Import SSP.



  2. In the Import SSP dialog, select the imported SSP file.



  3. In the Save package FMUControl_FMUTank as Modelica File dialog, save the Modelica file.



  4. Select the FMUControl_FMUTank model in the tree.
  5. In the Simulation pane, specify the Stop time for the simulation, and click Simulate in the Simulation tab..

    The compiler must be set up for the simulation to work. To learn more about setting up the compiler, refer to Help Documents in the Tool tab of the Dymola application.



  6. Select the required variables from the simulation results in the Variables Browser. The graph for the selected variables is available in the simulation pane.


Manually exporting the CSV file from the Dymola

To export the CSV file from Dymola

  1. In the Variable Browser, right-click the required results and select Export Result>All.




  2. In the Export Result-All dialog, select the location to export the CSV file.



This exported CSV file can be loaded into the Results Player to display numerical values from a CSV file directly in composite structure diagrams.

Sample model

The model used in the figures is the WaterTankFMI.mdzip sample, bundled with the modeling tool. 

To open the sample

  • Find the sample in the modeling tool <install_root>\samples\simulation\fmi\WaterTankFMI.mdzip