how do I obtain a transfer function having an input and an output?

Question

my problem is the next one: I have an input signal and an output one. i need to find a transfer function in this form H(s)=1/(as^2+bs+c). my goal is to have a,b and c.

Answer 1

let W be the tf, I the input and O the output.

in laplace IW=O, then you just need to do O/I and simplify it to get the W in the form you want,even if it would be better and more general to write it in the bode form.