Simulink Control Design™ - MathWorks

• Use a To Workspace block to write the data to the MATLAB workspace as a structure
  containing timeseries data. The Save format parameter of the To Workspace block
  must be Timeseries. The structure has the following fields:
  
  
  • Ready — Logical signal indicating which time steps are included in the estimation
    computation (1) and which are excluded (0). For instance, for sinestream mode,
    this signal is 1 only for data that falls within the periods determined by the
    Number of settling periods and Number of estimation periods parameters. In
    superposition mode, the signal is 1 only for data that falls within the window
    described in “Experiment Length and Data-Collection Window in Superposition
    Mode” on page 16-101.
  
  
  • Perturbation — Sinusoidal perturbations Δu applied to the plant
  
  
  • PlantInput — Plant input signal u + Δu, where u is the signal collected at the
    block input port y
  
  
  • PlantOutput — Plant output signal collected at block input port y
  
  
  
  


• Use Simulink data logging to write the data to the workspace as a
  Simulink.SimulationData.Dataset object. In this case, the structure containing
  the four timeseries signals is stored in the Values field of the resulting dataset. For
  instance, suppose that the model is configured to save the logged data to a variable
  logsout, and data is the only logged port. In that case, the structure is contained in
  logsout{1}.Values.

You can use the data from this port to perform the frequency-response estimation offline.

For instance, you can compute the estimated frequency response in MATLAB by passing

the structure to the frestimate command. For more information about accessing and

using the experiment data, see “Collect Frequency Response Experiment Data for Offline

Estimation” on page 6-23.

Data Types: single | double

frd — Estimated frequency responses

vector

The signal at this port contains the estimated frequency responses of the plant, in a

vector with one entry for each frequency specified in the Frequencies parameter. You

can write this signal to the MATLAB workspace using a To Workspace block, or use

Simulink data logging to write the data to the workspace as a

Simulink.SimulationData.Dataset object.

Typically, the best estimation is achieved at the end of the experiment. For that reason,

you might not need to log all historical data at this port. Instead, you can discard the

16 Blocks — Alphabetical List