CLOSED-LOOP SUPPRESSION OF CHAOS IN NONLINEAR DRIVEN OSCILLATORS

This paper discusses the suppression of chaos in nonlinear driven osci llators via the addition of a periodic perturbation. Given a system or iginally undergoing chaotic motions, it is desired that such a system be driven to some periodic orbit. This can be achieved by the addition of a weak periodic signal to the oscillator input. This is usually ac complished in open loop, but this procedure presents some difficulties which are discussed in the paper. To ensure that this is attained des pite uncertainties and possible disturbances on the system, a procedur e is suggested to perform control in closed loop. In addition, it is i llustrated how a model, estimated from input/output data, can be used in the design. Numerical examples which use the Duffing-Ueda and modif ied van der Pol oscillators are included to illustrate some of the pro perties of the new approach.