The state variables approach

Abstract

The design methods presented in Chaps. 5 and 6 constitute what is now known as classical control. One of the features of classical control is that it relies on the so-called input–output approach, i.e., the use of a transfer function. This means that a transfer function is like a black box receiving an input and producing an output, i.e., nothing is known about what happens inside the black box. On the contrary, the state variable approach allows us to study what happens inside the system.