Networked Control Systems: The Communication Basics and Control Methodologies

Yun-Bo Zhao,Jinhui Zhang,Peng Shi,Xi-Ming Sun

doi:10.1155/2015/639793

Abstract

As an emerging research field, networked control systems have shown the increasing importance and attracted more and more attention in the recent years. The integration of control and communication in networked control systems has made the design and analysis of such systems a great theoretical challenge for conventional control theory. Such an integration also makes the implementation of networked control systems a necessary intermediate step towards the final convergence of control, communication, and computation. We here introduce the basics of networked control systems and then describe the state-of-the-art research in this field. We hope such a brief tutorial can be useful to inspire further development of networked control systems in both theory and potential applications.

Highlights

As an emerging research field, networked control systems have shown the increasing importance and attracted more and more attention in the recent years
“Networked control systems” (NCSs) are the name of a general class of control systems where “the control loop is closed via a serial communication network” [1]
In NCSs, the data have to be transmitted through the communication network, and the nature of the Internet and other variations of data networks means that perfect data exchanges among the control components are essentially unavailable

Summary

Introduction

“Networked control systems” (NCSs) are the name of a general class of control systems where “the control loop is closed via a serial communication network” [1]. The data packet dropout (the data packet may be missing during transmission), and the time synchronization issue (different control components may work on different clocks) [9] These communication constraints can greatly degrade the system performance or even destabilize the system at certain conditions, while simple extensions of conventional control approaches cannot be obtained directly in a networked control environment [10,11,12,13,14,15,16]. From a general perspective of system structure, NCSs may contain two different structures [20]: the “direct structure” (Figure 1) and the “hierarchical structure” (Figure 2) The latter is different from the former as a local controller is present and the communication network is used to close the loop between the main controller and the local system. Most available works on NCSs to date have focused on the direct structure, which is the main focus of this brief tutorial

The Basics of Networked Control Systems

The Research on Networked Control Systems

Conclusions