Robust Control Toolbox™

Create options object for use with robuststab and robustperf

Syntax

• opts = robopt 
  opts = robopt('name1',value1,'name2',value2,...) 
  

Description

opts = robopt (with no input arguments) creates an options object with all the properties set to their default values.

opts = robopt('name1',value1,'name2',value2,...) creates a robopt object in which specified properties have the given values. Any unspecified property is set to its default value. It is sufficient to type only enough leading characters to define the property name uniquely. Case is ignored for property names.

robopt with no input or output arguments displays a complete list of option properties and their default values.

Fields

The following are the robopt object properties:

Object Property	Description
Display	Displays progress of computations {`on';'off'}. Default is 'off'
Sensitivity	Computes margin sensitivity to individual uncertainties {`on';'off'}. Default is 'on'.
VaryUncertainty	Percentage variation of uncertainty used as a stepsize in finite-difference calculations to estimate sensitivity. Default is 25.
Mussv	Option used in internal structured singular value calculations (when calling mussv). Default is 'sm9'.
Default	Structure, field names are robopt properties, and values are the default values.
Meaning	Structure, field names are robopt properties, and values are the text description of the property.

Example

You can create a robopt options object called opt with all default values.

• opt = robopt 
  Property Object Values: 
              Display: 'off' 
          Sensitivity: 'on' 
      VaryUncertainty: 25 
                Mussv: 'sm9' 
              Default: [1x1 struct] 
              Meaning: [1x1 struct] 
  

An elementary finite-difference scheme is used in estimating local sensitivities. The property VaryUncertainty denotes the step size used in estimating the derivatives necessary in computing sensitivities.

In the following statements, you are requesting that the sensitivity of the robust stability margin calculation to a 50% variation in individual uncertainties be calculated. The robopt options properties 'Sensitivity' and 'VaryUncertainty' are set individually.

• opt = robopt; 
  opt.VaryUncertainty = 50; 
  opt 
  Property Object Values: 
              Display: 'off' 
          Sensitivity: 'on' 
      VaryUncertainty: 50 
                Mussv: 'sm9' 
              Default: [1x1 struct] 
              Meaning: [1x1 struct] 
  

See Also
dkitopt     Creates an options object for dksyn

robuststab  Calculates stability margins of uncertain systems

robustperf  Calculates performance margins of uncertain systems

wcgopt      Creates a wcgain option object

wcsens      Calculates worst-case sensitivities for a feedback loop

wcmargin    Calculates worst-case margins for a feedback loop

Provide feedback about this page

repmat

robustperf

© 1984-2008- The MathWorks, Inc.    -   Site Help   -   Patents   -   Trademarks   -   Privacy Policy   -   Preventing Piracy   -   RSS