Output tracking control of networked control systems via delay compensation controllers

In this paper, the problem of networked output tracking control is investigated by considering the delay compensations in both the feedback and forward channels in networked control systems. The delayed output measurements are treated as a special output disturbance, and the feedback channel delay is compensated with the aid of an extended functional observer. For the delay in the forward channel, the buffer and packet-based delay compensation approaches are presented, respectively. Then, the stability analysis is performed for the networked closed-loop systems. Finally, a servo motor control system is used to demonstrate the effectiveness of the proposed new design scheme.