Simulink Control Design™ - MathWorks

• Estimate the frequency response of a system modeled in Simulink, without modifying
  the model. This approach is sometimes called offline frequency response estimation.


• Estimate the frequency response of a physical plant during real-time operation. This
  approach is called online frequency response estimation.

The following table summarizes some of the differences between offline and online

estimation and the tools you use to perform them.

Goal Tool More Information

Estimate frequency

response of a system

modeled in Simulink without

modifying the model

• Interactive workflow —
  Linear Analysis Tool


• Command-line workflow
  — frestimate
  command
  
  
  • “Estimate Frequency
    Response Using Linear
    Analysis Tool” on page 5-
    7
  
  
  • “Estimate Frequency
    Response at the
    Command Line” on page
    5-18
    Deploy frequency response
    estimation algorithm for
    real-time estimation of a
    physical plant
  
  
  
  

Frequency Response

Estimator block

“Deploy Frequency

Response Estimation

Algorithm for Real-Time

Use” on page 6-11

Perform online estimation of

a plant modeled in Simulink,

such as to validate

estimation parameters

before deployment

Frequency Response

Estimator block

“Online Estimation Using

Plant Modeled in Simulink”

on page 6-6

Basic Estimation Workflow

For offline estimation, the basic frequency response estimation workflow includes the

following steps:

(^1) Specify the portion of the model you want to estimate. You do so by configuring
linearization analysis points that specify the inputs and outputs for estimation.
(^2) Specify an operating point for estimation. Generally, you perform estimation at a
steady-state operating point. You can find such an operating point by trimming the
model.
5 Frequency Response Estimation