A transfer function out of a complex function
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Hi everyone, got this problem when trying to design a PID controler, so the function is here:
L=(4*exp(-t)+4*t+6)/10
i just can't get it right with all this num and den coefficients since this is a combination of ordinary function and an exponential fucntion. the question is: how do i turn it to a transfer function? got lost really.
Thanks, Sydney.
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Answers (2)
David Sanchez
on 5 Jun 2013
substitute in your L function:
exp(x) = 1 + x + (x^2)/4 % Taylor expansion
Operate until you obtain your num and den, then:
my_sys = tf( num, den )
2 Comments
Azzi Abdelmalek
on 5 Jun 2013
If L is your impulse response, Maybe L is
%L(t)=0.1(4exp(-t)-4t+6)u(t) % u(t) is a step function
The transfer function of your system is the Laplace transform of your impulse response
%L(p)=0.1*(4*1/(p+1)-4*1/p^2+6/p)
%L(p)=0.4/(p+1)-0.4/p^2+0.6/p=(p^2+0.2p-0.4)/(p^3+p^2)
num=[1 0.2 -0.4]
den=[1 1 0 0]
H=tf(num,den)
11 Comments
Azzi Abdelmalek
on 5 Jun 2013
Do you mean
h: your output signal
m,c,k and F are constant
What about your input signal?
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