Estabilidad en un Sistema de Control

In 1985, P.J. Holmes stated the non linear systemx¨ + x˙ + g(x) = zz˙ + z = xwith the purpose of analysing certain kind of control system of feedback. Taking g(x) =x(x2 1) and x˙ = y a non linear systems is obtained which present a non hyperbolic point in its origin whose stability id being studied.