Feedback Control Theory

Without control systems there could be no manufacturing, no vehicles, no computers, no regulated
environment—in short, no technology. Control systems are what make machines, in the broadest
sense of the term, function as intended. Control systems are most often based on the principle
of feedback, whereby the signal to be controlled is compared to a desired reference signal and the
discrepancy used to compute corrective control action. The goal of this book is to present a theory
of feedback control system design that captures the essential issues, can be applied to a wide range
of practical problems, and is as simple as possible.