I am currently taking a course in control theory.
In control theory the system or impulse response is usually an algebraic expression in Laplace domain. Much of the work done in school is to find this transfer function or shift the pole of this transfer function around to make the system stable.
But this all feels a bit unrealistic. How so? Suppose I wanted to find the transfer function of my cell phone, how would I ever go about doing this? How do I know that the input-output relationship would be characterized by a simple differential equation? And how would I ever go about "shifting" the poles in real life so to achieve stable or some desired operation?
Can someone provide me with a realistic example of how a real device can be characterized using control theory (i.e. so that the system transfer function is known) and what it physically means to design the controller or shift the poles. 100 points for most real life example. Thanks!