Overview¶

The configuration has to be JSON-formatted. It is divided into the following categories:

Client: basic configuration of the Lablink client
FMU: basic configuration related to the FMU simulator
InitialValues: configuration of initial values of the FMU instance
Input: configuration of the client’s inputs, each associated to an FMU input variable
Output: configuration of the client’s outputs, each associated to an FMU output variable

In the following, the configuration parameters for these categories are listed.

Basic Lablink Client Configuration¶

Required parameters:

ClientName: client name
GroupName: group name
ScenarioName: scenario name
labLinkPropertiesUrl: URI to Lablink configuration
syncHostPropertiesUrl: URI to sync host configuration

Optional parameters:

ClientDescription: description of the client
ClientShell: activate Lablink shell (default: false).

FMU Simulator Configuration¶

Required parameters:

URI: URI to the FMU. Paths can be specified as fmusim://relative/path/to/my.fmu, where the path will be interpreted relative to the path specified via system property dmuDir. For instance, using option -DfmuDir=/a/b/c when starting the plotter client and specifiying plotter://x/y/z.fmu will result in CSV files being written to directory `/a/b/c/x/y/z.fmu.

Optional parameters:

DefaulUpdatePeriod_ms

default period of the synchronization schedule in milliseconds (default: 1000)

LoggingOn

turn on/off log messages from the FMU (default: false)

IntegratorType

select integrator type (default: bdf):

eu: Forward Euler method
rk: 4th order Runge-Kutta method with constant step size
abm: Adams-Bashforth-Moulton multistep method with adjustable order and constant step size
ck: 5th order Runge-Kutta-Cash-Karp method with controlled step size
dp: 5th order Runge-Kutta-Dormand-Prince method with controlled step size
fe: 8th order Runge-Kutta-Fehlberg method with controlled step size
bs: Bulirsch-Stoer method with controlled step size
ro: 4th order Rosenbrock Method for stiff problems
bdf: Backwards Differentiation formula from Sundials. This stepper has adaptive step size, error control and an internal algorithm for the event search loop. The order varies between 1 and 5. Well suited for stiff problems.
abm2: Adams-Bashforth-Moulton method from sundials. This stepper has adaptive step size, error control, and an internal algorithm for the event search loop. The order varies between 1 and 12. Well suited for smooth problems.

ModelTimeScaleFactor

simulation time scaling factor, i.e., speed-up or slow-down of progress of logical simulation time (default: 1)

ModelStartTime_s

start time (logical simulation time) for FMU model (default: 0)

TimeDiffResolution_s

resolution for resolving time differences in seconds (default: 1e-4)

Optional parameters for DynamicFmuModelExchangeAsync only (for expert users):

NIntegratorSteps: number of integration intervals within a synchronozation period (default: 2)
NSteps: number of integration steps within each integration interval for fixed-step integrators (default: 2)

Initial Value Configuration¶

Configuration for each FMU model variable that should be initialized with a specific (non-default) value:

VariableName: name of the FMU variable
DataType: type of the FMU variable, allowed values are double, long, boolean and string
Value: initial value

Input and Output Configuration¶

Required configuration parameters for each input/output:

VariableName: name of the client’s input/output port, has to correspond to an appropriate FMU variable
DataType: data type of the client’s input/output port, has to be compatible to the corresponding FMU variable type; allowed values are double, long, boolean and string

Optional configuration parameters for each input/output:

Unit: unit associated to the client’s input/output port

Example Configuration¶

The following is an example configuration for a DynamicFmuModelExchangeAsync client:

{
  "Client": {
    "ClientDescription": "FMU async simulator example.",
    "ClientName": "TestFMUAsync",
    "ClientShell": true,
    "GroupName": "FMUSimDemo",
    "ScenarioName": "FMUSimAsync",
    "labLinkPropertiesUrl": "http://localhost:10101/get?id=ait.all.all.llproperties",
    "syncHostPropertiesUrl": "http://localhost:10101/get?id=ait.test.fmusim.async.sync-host.properties"
  },
  "FMU": {
    "DefaulUpdatePeriod_ms": 1000,
    "IntegratorType": "bdf",
    "TimeDiffResolution": 1e-06,
    "URI": "file:///C:/Development/lablink/lablink-fmusim/src/test/resources/zigzag.fmu"
  },
  "InitialValues": [
    {
      "DataType": "double",
      "Value": 0,
      "VariableName": "integrator.y_start"
    },
    {
      "DataType": "double",
      "Value": 0.8,
      "VariableName": "k"
    }
  ],
  "Input": [
    {
      "DataType": "double",
      "Unit": "none",
      "VariableName": "k"
    }
  ],
  "Output": [
    {
      "DataType": "double",
      "Unit": "none",
      "VariableName": "x"
    },
    {
      "DataType": "double",
      "Unit": "none",
      "VariableName": "derx"
    }
  ]
}