Chapter 1 Robust feedback Control Chapl er n conl ains a general presenl al ion of classical feedback conl rol, wilh an emphasis on robusl ness l o mo del uncerl ainl y of feedb ack sysl ems The need lo develop design mel hods, hal explicil ly can handle mo del uncerl ainl y is demons ral ed 1.1 Feedback and Uncertainty Conl rol of a dy namical process by feedb ack of a measured oul pul is a well(known principle pically wil h i he primary ob jeclive of keeping I he oul pul of I he process close lo a given e(s K(s) G(s Standard feedback configuration Fh Figure nn, a sl andard feedback configur al ion is shown, consis ing of a process G(s)and a compensa or K(s). For sy sl ems wil h feedb ack I he following imp orl anl properl ies can ofl en oys ems I hal are unsl able from nal ure, can be sl abilized fecl of exl ernal disl t The I ime cons anl s or chara eris ic frequencies of I he sysl em can be shifl ed Finally, ofl en Ihe above properlies can be obl ained even wil h an in complel e knowledge￾
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