A continuous plant model uses signal data that is smooth and uninterrupted in time. There is signal data for each time value. A continuous plant model uses a continuous solver (any solver other than an explicit discrete solver). The solver can be fixed-step or variable. The model includes blocks from the Continuous library in Simulink®, such as an Integrator block.
To load data to represent a continuous plant, consider using either a root-level input port or a From Workspace block. Using a From Workspace block can be useful when loading data to a port buried deep within a model.
For the signal data:
Specify a time vector and signal values extracted from a continuous plant. For example, extract from data that you acquire experimentally or from the results of a previous simulation.
Use any of the data formats listed in Loading the Data. Here are recommended formats for the following imported data sources:
Another simulation —
An equation — MATLAB® time expression
Experimental data — MATLAB
structure with time, a structure without time, or a data array
For structure data, see Specify Time Data.
This example illustrates how to reuse signal logging data from the simulation of one model in the simulation of a second model. For more information, see Load Signal Logging Data.
When reusing data from a variable step size simulation for simulation in another model, the second simulation must read the data at the same time steps as the first simulation.
This model uses the
ode15s solver and produces
To use the output of this model as input to the simulation of another model, log the signal that you want to reuse. In the Simulink Editor, select that signal, click the Simulation Data Inspector button arrow and click Log Selected Signals to Workspace.
Note: To enable signal logging, select the Configuration Parameters > Data Import/Export > Signal logging parameter. This model has Signal logging enabled.
Simulate the model.
Simulating the model saves a variable-step signal to the workspace,
logsout variable. The signal logging
output is a
to access the logged data. The logged data for individual signals
is stored in
For this model, there is one logged signal:
Open a second model, named
You can configure this second model to simulate using the logged data from the first model. In this example, the second model uses a root-level Inport block to import the logged data. The Inport block has the Interpolate data option selected.
In the second model, select the Configuration Parameters > Data Import/Export > Input parameter.
to specify the
StepResponse signal element:
Specify that for the second model, the Simulink solver
runs at the time steps specified in the saved data (
In the Data Import/Export pane, set the Output options parameter
Produce additional output and the Output
times parameter to:
Simulate the second model.
Note: Simulink does not feed minor time-step data through root input ports. For details about minor time steps, see Minor Time Steps.