The closed-loop characteristic equation G(s) K R(S)1+G(S)H(S) TS'+S+K S+250, 5+0 1+G(s)H(S)=0■ +24aS+ 0 2=-5on±jon1-2=-on±j the damped natural frequencyThe closed-loop characteristic equation: 2 2 2 2 1 ( ) ( ) 2 ( ) ( ) ( ) n n n Ts s K s s K G s H s G s R s C s     + + = + + = + = 1+ G(s)H(s) = 0 2 0 2 2 s +  n s +n = n n n d s s = −   j − = −  j 2 1 , 2 1 2 d =n 1− – the damped natural frequency