Networked control systems: random delay compensation with play-back buffers and smith predictor

The benefits brought by network communication in the context of closed loop control stimulated a great research focus on the networked control systems (NCS).Multiple solutions and theories were emitted and proposed throughout the time aiming for eliminating the drawbacks brought by the specific network characteristics such as variable time delay and packet loss.We propose herein a combination between playback buffers, which eliminate the randomness of the network delay, and a Smith predictor which will compensate the resulting process time delay.The performances of the proposed control system will be compared with those obtained by using an unbuffered PID controller.