Simulink Control Design™ - MathWorks

Then remove the SOF block from the tunable block list and re-parameterize the PI blocks

as full-blown PIDs with the correct loop signs (as inferred from the first design).

PID = pid(0,0.001,0.001,.01); % initial guess for PID controllers

removeBlock(ST0,'SOF');

setBlockParam(ST0,...

'PI1',tunablePID('C1',PID),...

'PI2',tunablePID('C2',-PID),...

'PI3',tunablePID('C3',-PID));

Re-tune the three PID controllers and plot the closed-loop step responses.

ST2 = systune(ST0,AllReqs);

Final: Soft = 4.94, Hard = -Inf, Iterations = 67

T2 = getIOTransfer(ST2,{'theta-ref','phi-ref','r-ref'},{'theta','phi','r'});

figure, step(T2,5)

13 Control System Tuning Examples