About Excitations

Excitations are the inputs to the scenario; a collection of objects that perform various operations (for example setting of initial conditions) to be simulated.

Important: The definitions of excitations and probes depends on the behavior selection. You should select the behavior before creating the excitations and probes. If the behavior selection is modified after the creation of excitations and probes, you must edit them again; the command updates them, i.e. removes the invalid variables from excitations and probes.

This page discusses:

See Also
About Behavior Experience
Defining and Handling Initial Conditions
Defining Forced Values
Importing and Modifying Initial Steady State Values from Result

Available Excitations in Behavior Experience App

The following excitations are currently available in the Behavior Experience app.

Notes:
  • Defining or modifying excitation values do not modify the model values.
  • The excitations listed below are unique for a scenario, that is, you cannot have, for example, two Initial Condition Values for the same signal.

Initial Condition Values

Initial condition values can be defined to be used in the simulation.

The initial conditon values are Knowledge parameters.

Forced Values

Parameters and input ports can be forced.

Initial Steady State Values

The initial state for a scenario can be defined by importing from the results of another scenario.

Here is an overview of how the import is performed:

For each parameter or state variable, the command tries to find the corresponding name in the result file. If the variable is found, the value of the variable is taken at that time point specified by the user in the dialog box. If there is no such time point in the time line of the result, then a linear interpolation is used to compute the value of the chosen time point. The interpolated value is rounded to the nearest valid value (for Integer or Boolean variable for example).

Remarks:

  • The start time is not modified when the initial state is imported (specifically, it is not set to the time value of the imported state).
  • No link between the selected result and the created initial state is managed. If the results are updated, the created initial state is not impacted.

Imported values cannot be edited, but they can be overridden.

Note: This feature is only available for Modelica behaviors.

Priority Order for Initial Values for Simulation

The excitation values are used in priority order when defining start values for simulation.

When simulating with the start time t, each variable is given a value in the following priority order:

  1. The value from Forced Values excitation.
  2. The value from Initial Steady State excitation, if no Forced Value is available at that start time.
  3. The value from Initial Condition excitation, if none of the above are available at that start time.
  4. The value from Default Values, if none of the above are available at that start time.