You can use the Linear System Analyzer for SISO Design Tasks to specify both time and frequency domain requirements in analysis plots. Adding and editing design requirements is similar to those illustrated in the Graphical Tuning window.
To add design requirements, you must open the Linear System Analyzer from
the SISO Design Task in the Control and Estimation Tools Manager.
Design requirements are not available from a Linear System Analyzer that is opened
For row or column arrays of LTI models, the design requirements are for the nominal model that you are designing the controller for. You can analyze the effects of this controller on the remaining models. See Control Design Analysis of Multiple Models in the Getting Started Guide.
The design requirements for Bode, Root Locus, and Nichols plots can be applied to both graphical tuning windows and the Linear System Analyzer. See Design Requirements for information on graphical tuning design requirements.
You can also specify the following design requirements for both step and impulse response plots:
Upper time response bounds — Creates an upper amplitude bound for a specified time duration.
Lower time response bounds — Creates a lower amplitude bound for a specified time duration.
If you are using a step response plot, you can also specify the following design requirement:
Step response bounds — Creates a group of upper and lower time response bounds, in the shape of a step response envelope, to encompass your specified design requirement parameters.
This example shows you how to create a lower bound time response design requirement.
At the MATLAB® prompt, type the following:
load ltiexamples controlSystemDesigner(Gservo)
From the Analysis Plot pane, select a step response for the closed-loop system. See Analysis Plots if you are unfamiliar with this task.
Right-click on the plot and select Design Requirements > New.
Lower time response bound from
the Design requirement type menu.
Set Time from 0.1 to 0.5 s.
Set Amplitude from 0 to 0.8. Your New Design Requirement window should look like this.
Click OK. This adds the design requirement to the plot. Your step response should look like this.
Now, when you adjust or tune the controller, you can use the plot to observe how well the response meets your design requirements.