Is it genetic algorithm code from Steve Brunton ?

You need to modify your cost function. you need to add term settling time and steady-state error in your cost function J.

hi Waheed Ur Rehman

yes it is the Steve brunton code. How can I add settling time and steady state error to the cost function?

The cost function is currently an LQR cost function and I imagine I would have to use a different cost function all together to add settling time and steady state error would I not? A cost function such as ITAE for example

sys = tf([1 5 5],[1 1.65 5 6.5 2]);

S = stepinfo(sys)

S.RiseTime

S.SettlingTime

I hope this code will help you. You can replace sys with y

Hi Waheed Ur Rehman

I appreciate the code provided but this does not help with the cost function since it is based on Q and u weighting and not settling time or rise time. I am currently trying an ITAE cost function in the hopes it will work. It is useful to know commands which call the settling time and rise time although I am not sure they are able to be called and used within the present code effectively.

S = stepinfo(5*ClosedLoop,t) ;

r= S.SettlingTime

J=(dt*sum(Q(1-y(:)).^2+R*u(:).^2))+r

hi Waheed Ur Rehman

I will get back to you later in time as I am not sure how to properly implement the suggested code.

hi Waheed Ur Rehman I tried implementing the code as specified and get the following error.

Error using stepinfo (line 57)

The input arguments "Y" and "YFINAL" of the "stepinfo" and "lsiminfo" command must have compatible

sizes.

Code used

function J = pidtest(G,dt,parms)

s = tf('s');

K = parms(1)+ parms(2)/s + parms(3)*s

Loop = series(K,G);

ClosedLoop = feedback(Loop,1);

t = 0:dt:0.005; % this indicates length of time to show

[y,t] = step(ClosedLoop,t);

S = stepinfo(5*ClosedLoop,t) ;

r= S.SettlingTime;

u = lsim(K,1-y,t);

Q = 1;

R = 0.000005;

J= (dt*sum(Q(1-y(:)).^2+R*u(:).^2))+r

step(5*ClosedLoop,t)

h = findobj(gcf,'type','line');

set(h,'linewidth',1);

drawnow

please use " debugging " to find an error point

I specified the error above. The system cannot stand having both the step() command and stepinfo command by the seems ass it meeses with Y and Yfinal

Send me code I will check it. [email protected]

Waheed Ur Rehman I sent you an email, hope it got through.

check code on your email address

hi Waheed Ur Rehman

I ran the code and it works amazing in the matlab coding enviroment although when put onto the real system I get high oscillatory behaviour.

I truly appreciate the work you have done and can not thank you enough. I can make you as best answer if you wish. I am not sure how I can make it work on the simulink although I may get lucky.