Rules for plotting root locus Content Rules 1 Continuity and Symmetry Symmetry rule Starting and end points n segments start from n open-loop Number of segments poles, and end at m open-loopzeros and(n-m) zeros at infinity Segments on real axis On the left of an odd number of poles or zeros Asymptote n-m segments N(2k+1) 丌,k=0,±1,+2, n-m 5 Asymptote ∑ (-p)-∑(-=) 上大字Content Rules 1 Continuity and Symmetry Symmetry Rule 2 Starting and end points Number of segments n segments start from n open-loop poles, and end at m open-loop zeros and (n-m) zeros at infinity. 3 Segments on real axis On the left of an odd number of poles or zeros 4 Asymptote n-m segments： 5 Asymptote 3 Rules for Plotting Root Locus n m p z n j m i j i − − − − =   =1 =1 ( ) ( )  , 0, 1, 2, (2 1) =   − + k n m k ＝ 