“…Major difficulty in modeling drilling process is that dynamics of the process are not completely understood (Chung and Tomizuka, 2001). Different modeling and control techniques using empirical methods, fuzzy logic, neural network and transfer function models of different order are available in literature (Stone and Krishanmurthy, 1996;Chung and Tomizuka, 2001;Kawaji et al, 2001;Kim et al, 1994Kim et al, , 2003Haber-Haber et al, 2007;del-Toro et al, 2007;Sheng et al, 2000;Furness et al, 1999;Oh et al, 2003;Kawaji and Suenaga, 1995). Damage due to delamination is also related to torque produced during drilling (Singh and Bhatnagar, 2006a, b).…”