Science & Engineering Research Support soCiety (SERSC)
Moreover, after stabilizing the system, the authors also need to modify the system which is unstable due to time-delay elements by internal model controller considering the uncertainty of control object and time-delay elements. Time-delay will happen during long distance communication. Therefore, when they have a control object in a long distance, the transmitted reference signal will certainly be delayed. For this reason, even though they stabilize the control object, it will be an unstable system by time-delay elements.