Simulink Control Design™ - MathWorks

Time-Domain Specifications

This example gives a tour of available time-domain requirements for control system

tuning with systune or looptune.

Background

The systune and looptune commands tune the parameters of fixed-structure control

systems subject to a variety of time- and frequency-domain requirements. The

TuningGoal package is the repository for such design requirements.

Step Command Following

The TuningGoal.StepTracking requirement specifies how the tuned closed-loop

system should respond to a step input. You can specify the desired response either in

terms of first- or second-order characteristics, or as an explicit reference model. This

requirement is satisfied when the relative gap between the actual and desired responses

is small enough in the least-squares sense. For example,

R1 = TuningGoal.StepTracking('r','y',0.5);

stipulates that the closed-loop response from r to y should behave like a first-order

system with time constant 0.5, while

R2 = TuningGoal.StepTracking('r','y',zpk(2,[-1 -2],-1));

specifies a second-order, non-minimum-phase behavior. Use viewGoal to visualize the

desired response.

viewGoal(R2)

Time-Domain Specifications