Compensator in Internet based telecontrol system

When Internet exists in the forward path and feedback path in the servo, this system can control any plant on the node of Internet at any time. Network time delay and its uncertainty property are the main impediment to develop Internet based telecontrol system. Theory and experiment prove that dynamic compensator could change Internet based telecontrol system from unstable state to stable state, but performance is influenced by predicting error of network time delay. It also can be proved by theory and experiment that variable structure compensator could weaken the steady-state error caused by more-sampled case, and improve control performance.