Control of chaos by nonfeedback methods in a simple electronic circuit system and the FitzHugh-Nagumo equation

Various control algorithms have been proposed in recent years to control chaotic systems. These methods are broadly classified into feedback and nonfeedback methods. In this paper, we make a critical analysis of nonfeedback methods such as (i) addition of constant bias, (ii) addition of second periodic force, (iii) addition of weak periodic pulse, and (iv) entrainment control. We apply these methods to a simple electronic circuit, namely, the Murali-Lakshmanan-Chua circuit system and FitzHugh-Nagumo equation. We make a comparative study of the various features associated with the algorithms.