MATLAB: The use of the linear quadratic requlator method in the state space controller and observer design

Control System Toolboxlinear quadratic regulator fu

hi guys,I am new in matlab and simulink. can you help me find a degin method to find the values of the R and Q matrices that are used to find the optimal values of the state controller k that optimize the objective function. my problem how I can relate the required performance of nonovershoot and zero stedy state error for the output to the values of Q and R matrices.

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The matrices R and Q are essentially design parameters or weights that you have to choose as part of the control system design, there's no automated way of selecting those (as far as I know). However, you can use function like lqr to compute the optimal state feedback matrix K. Check out the other functions under LQR/LQG Design.

HTH,

Arnaud

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Yes, a MATLAB Function block would indeed do the trick. Suppose you make a function:

function output = myLQR(error,param)

Where param is the the value of that one element of A (let's say, A(5,5)) passed in as a time-varying signal to the MATLAB function. So, in the function, you can say something like:

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- Sebastian

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