Chapter Two automatic Control b. Automatic control principle At beginning, it is come from the self-adjustment principle based on the feedback, and mainly used in industry process control. During the second world war, it is widely used in military, like radar. After the second world war, it has improved into the typical automatic control theory based on the transfer function, mainly in Si/So liner system After 1960s. with development of computer science and technology, automatic control theory comes into modern control theory with state space and optimal controlb. Automatic control principle At beginning, it is come from the self-adjustment principle based on the feedback, and mainly used in industry process control. During the second world war, it is widely used in military, like radar. After the second world war, it has improved into the typical automatic control theory based on the transfer function, mainly in SI/SO liner system. After 1960s, with development of computer science and technology, automatic control theory comes into modern control theory with state space and optimal control. Chapter Two Automatic Control