Section 1.1 A Brief History of Control Theory Classical Control Theory During the World Wars,the development of feedback control systems became a matter of survival. Tools:Frequency domain techniques Important results: Bode stability criterion(1927) o Nyquist stability criterion (1932) (An indispensable means for analyzing and designing control systems even today) Problems that need to be clarified for deeper and more comprehensive studies.For example: Mathematically,what is the objective of control system design? How is the control system optimized in the design? 4口+0：4定4生定9QC Zhang,W.D..CRC Press.2011 Version 1.0 6/31Section 1.1 A Brief History of Control Theory Classical Control Theory During the World Wars, the development of feedback control systems became a matter of survival. Tools: Frequency domain techniques Important results: Bode stability criterion (1927) Nyquist stability criterion (1932) (An indispensable means for analyzing and designing control systems even today) Problems that need to be clarified for deeper and more comprehensive studies. For example: 1 Mathematically, what is the objective of control system design? 2 How is the control system optimized in the design? Zhang, W.D., CRC Press, 2011 Version 1.0 6/31