“…To achieve these goals, various methods using different techniques have been proposed as follows: the flexible-joint controller model was first proposed in the study [9]. Since then, many control methods have been applied to improve the tracking performance of the FJM, such as proportional integral derivative (PID) control [6], [7], linear quadratic regulator (LQR). [17], fuzzy logic control [13], [14], sliding mode control (SMC) [4], [5], backstepping control [15], robust control [11] and neural network control [5], [6].…”