Design considerations for electronic chaos controllers

We analyze general possibilities of electronic implementations of chaos controllers. We consider in particular two classes of chaos controllers: those based on the OGY approach, and occasional proportional feedback (OPF) controllers. Influence of accuracy of digital implementation of the OGY algorithm and its partial hardware implementation is discussed in detail. We describe which parts of the algorithm can be implemented in hardware and how to build a feedback controller with computer-assisted goal determination. As a second task, we consider the OPF controller introduced by Hunt for stabilizing periodic solutions in autonomous chaotic systems. Its original version has a major drawback because it requires an external synchronizing signal. We describe a modified version of Huntʹs controller which obviates the need for an external synchronizing signal. Advantages and disadvantages of both methods from the implementation point of view are discussed in detail.