I have a line following differential drive robot with a PID control. I successfully tuned (try and error) the P,I,D constants for a good stability in low speeds, but when I increase the speed, everything goes sideways.
Therefore I want to solve this with a bit of a mathematical approach.
I started logging the error (setpoint-present sensor value;input for PID) and output (from the PID; motors get values: left = speed-output, right = speed+output).
My question is, whether it is possible to use this data in order to further improve the PID?