To prevent high-gain control and saturations, add a requirement that limits the gain from
reference to control signal (output of Notch block).
GL = TuningGoal.Gain('Reference','Notch',0.01);
Now retune the controller at the specified sampling rate and verify the tuned open- and
closed-loop responses.
ST2 = looptune(ST0,Control,Measurement,TLS,GL);
% Closed-loop responses
T2 = getIOTransfer(ST2,'Reference','Measured Position');
clf
step(T0,T1,T2,1.5), grid
legend('Original','Lead/lag','Lead/lag + notch')
Final: Peak gain = 1.04, Iterations = 44
Tuning of a Digital Motion Control System