> The result was too dependent on the "starting position".
PID controllers always control around a nominal operating point (which you pick), which is why deviation variables are typically used in the mathematical derivation. That's just the basis of the control algorithm.
This is what I tried (step, not impulse). Did not work well. The result was too dependent on the "starting position".
The course professor probably knew less about controls than I did. He was a computer engineering professor.