Consider the master system
For system (1) is chaotic, for certain -values it is related to the Lorenz, Lü and Chen system. Representing (1) in the form , the authors consider together with (1) the slave system . The goal of the authors is to find a control such that the slave system synchronizes the master system in finite time, that is, the corresponding error system
has the property that their solutions tend to zero in a finite time. Of course, this requires that the error system is not Lipschitzian in . The authors construct such a control by means of a control Lyapunov function. Moreover, they show that this control is robust against perturbations of some coefficients of (1).