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sdo.requirements.PZDampingRatio class

Package: sdo.requirements

Damping ratio bound


Specify bounds on the damping ratio of the poles of a linear system. You can then optimize the model response to meet these bounds using sdo.optimize. You can also use this object to specify overshoot bound.

You must have Simulink® Control Design™ software to specify damping ratio requirements.


damp_req = sdo.requirements.PZDampingRatio creates a sdo.requirements.PZDampingRatio object and assigns default values to its properties.

gainphase_req = sdo.requirements.PZDampingRatio(Name,Value) uses additional options specified by one or more Name,Value pair arguments. Name is a property name and Value is the corresponding value. Name must appear inside single quotes (''). You can specify several name-value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Input Arguments

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Use Name,Value arguments to specify properties of the requirement object during object creation. For example, requirement = sdo.requirements.PZDampingRatio('Type','>=') creates an sdo.requirements.PZDampingRatio object and specifies the Type property as a lower bound.



Damping ratio bound. Must be a finite scalar between 0 and 1.

Default: 0.7071


Requirement description, specified as a character vector. For example, 'Requirement on signal 1'.

Default: ''


Requirement name, specified as a character vector.

Default: ''


Damping ratio bound type, specified as one of the following values:

  • '<=' — Upper bound

  • '>=' — Lower bound

  • '==' — Equality bound

  • 'max' — Maximization objective

Default: '>='


evalRequirementEvaluate damping ratio bound on linear system
getOvershootConvert damping ratio to equivalent overshoot value
setOvershootSet overshoot to an equivalent damping ratio

Copy Semantics

Handle. To learn how handle classes affect copy operations, see Copying Objects.


Construct a damping ratio object and specify the damping ratio.

       r = sdo.requirements.PZDampingRatio;
       r.DampingRatio = 0.1;

Alternatively, you can specify the damping ratio during construction.

       r = sdo.requirements.PZDampingRatio('DampingRatio',0.1);


Use getbounds to get the bounds specified in a Check Pole-Zero Characteristics (Simulink Control Design) block.