using PID function in MATLAB

[andrewllewop]

Having issues with using the PID function in MATLAB:

whenever i try to use the pid function in matlab in the command window I get the message "undefined function or variables". But I am seeing examples where the PID function is used. eg C = pid(Kp,Ki,Kd). not sure if there is a missing toolbox, file or something. I've just started a Controls class so I am still a novice with using some of the features of MATLAB. If someone could tell me a fix for this. i'd appreciate it

Thanks in advance

 

[ArNvC]

try using this:

Kp = 1;
Ki = 1;
Kd = 1;

s = tf('s');
C = Kp + Ki/s + Kd*s

instead of C = pid(Kp,Ki,Kd)

 

[Usama Siddiqui]

it depends on the version of matlab you are using i suppose.the older versions doesnt have certain commands and the other problem could be that some files of your library might have been corrupted.