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Weird response to a step in matlab

Weird response to a step in matlab

Weird response to a step in matlab

I have this script which isn't making that much sense.

clear all
kp = 0.000065;
ki = 0;
kd = 0;
b = pid(kp,ki,kd);
d = (tf([1 0],[1]))
f = tf([11.53 1.068],[1 0.09834 6.263*10^(-5)])
velocity = feedback(b*f,d)
a = pole(velocity)
b = zero(velocity)

Looking at it's step input, you will see that the final value is incredible large considering that response is due to a step input.. i know something must be wrong but what is wrong?

RE: Weird response to a step in matlab

Nope.. i am testing a controller for a system, it doesn't reponds as i want it to.. that why i asking if I am doing something wrong.

RE: Weird response to a step in matlab

Looks to me like basic misunderstanding of some of the lesser travelled bits of Matlab: some of the longer, cleverer functions in the control system toolbox (which use names that IMO should be decorated, not simple). This little example explains nothing but shows what to do (i.e. how to create the right arguments to pass from one "function" to the next).


- Steve

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