R = TuningGoal.Margins('u',6,45);
In MATLAB, use an AnalysisPoint block to mark the location "u" (see “Building
Tunable Models” (Control System Toolbox) for details). In Simulink, use the addPoint
method of the slTuner interface to mark "u" as a point of interest (see “Create and
Configure slTuner Interface to Simulink Model” on page 10-210). Stability margins are
typically measured at the plant inputs or plant outputs or both.
The target gain and phase margin values are converted into a normalized gain constraint
on some appropriate closed-loop transfer function. The desired margins are achieved at
frequencies where the gain is less than 1. Use viewGoal to examine the requirement you
have configured.
viewGoal(R)
Loop Shape and Stability Margin Specifications