“…The OGY control method and the delayed feedback control presented by Pyragas (1992Pyragas ( , 2006 are the early works on controlling chaos via feedback. Recently, linear feedback control methods based on linearization and dynamic programming (Vincent andYu 1991, Merat et al 2009), nonlinear feedback control methods based on Lyapunov stability theory (Alasty and Salarieh 2007), sliding mode control (Konishi et al 1998, Arjmand et al 2008, backstepping method (Wu and Lu 2003, Yongguang and Suochun 2003, Yassen 2006) and some geometrical techniques (Tian and Yu 2000) have been widely used for chaos control in closed loop format. b) Model based and mode free control: If the control action u is calculated based on the information obtained from dynamical model of the system, the control technique is called model based method.…”