G(z)=1−pz−p
If the value of p satisfies 0≤p<1 there are no oscillations in the transient response.
Question: Why is that ↑ true? I know roughly what a transient response is but how is the relation between the position of the pole and the nature of the transient response?
Edit: In another paper by the same authors:
Enforcing the stability of the controlled system means ensuring that the pole p is non-negative and less than 1.
Now I'm completely out, stability does not depend upon the position of the pole as long as they are inside the unit circle of the z-plane I have thought?
Paper 2:
Look at the sentence short above eq. (10) on page 5
Paper 1 is not available on the internet as fas as I know. It's Antonio Filieri et al. "Software Engineering Meets Control Theory"
Answer
If you have a single real-valued pole, you get a term kp(n−n0)u[n−n0],n≥0, with some constant k and some delay n0≥0 in the system's impulse response (u[n] is the unit step). Clearly, if |p|≥1 the transient will never settle. If $-1
(−12)nu[n]={1,−12,14,−18,…}
So for a transient that decays (i.e., for the system to be stable) and that does not oscillate you need 0≤p<1.
Note that if you only have one real-valued pole p, stability implies $$-1
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