Error simple program PID
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Hello, I doing a pid project I have everything correct but this error come up what I should do?
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JOJO
2014-1-15
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Mischa Kim
2014-1-15
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which -all syms
and you should get something like
C:\Program Files\MATLAB\R2013b\toolbox\symbolic\symbolic\syms.m
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Mischa Kim
2014-1-15
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Interesting. The code is just fine.
Try this: copy-and-paste the code from your question above and paste it into the MATLAB command window. Execute.
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Mischa Kim
2014-1-15
Also, please post comments as comments.
David Sanchez
2014-1-15
I tried your code (copy-paste) and it works. Make sure you have the Symbolic Math toolbox:
Start (bottom left corner)-> Toolboxes
You should see the all the toolboxes of your system, if you do not locate the Symbolic Math toolbox, you can not use
syms
Carla
2014-1-15
Is there a reason you need to do this with syms? At least in the code you showed, it doesn't look like you are using any Symbolic Toolbox functionality. You can achieve the same exact result using only Control System Toolbox as follows:
num=1; % Numerator
den=[1,3,1]; % Denominator
G=tf(num,den); % Transfer Function
H=1; % Negative Feedback Loop with Unity Feedback
Kp=1; % Increment these three varaibles to give desired output
Ki=0;
Kd=0;
C=pid(Kp,Ki,Kd); % Controller Function
T=feedback(C*G,H); % C in series with G with negative feedback H
step(T) % Step Response with Controller
If there is some reason elsewhere in your program that you need syms functionality, I suppose this won't solve your problem!
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