“…Some fundamental methods for robot force control have been developed in the last two decades. These control methods can be summarized as stiffness [4], impedance [5], admittance, hybrid position/force, hybrid impedance, parallel position/force, pure force control [6,7], and computed torque control [8]. In addition, some advanced methods have been developed such as fuzzy [9], adaptive [10], robust [11], vision based [12], and learning algorithms [13].…”