Self-regulating systems with feedback loops, i.e., the routing back of the output of a system to its input, have existed since antiquity and have since become an integral part of modern technology.

Machines and processes are controlled using many strategies, from simple ladder logic to custom algorithms for specialized process control, but proportional-integral-derivative (PID) is the most ...

In my previous column, I showed bode plots for different types of transfer functions. I also touched on the basic principles of closed loop systems. As a refresher, the gain crossover frequency ...