de Oliveira Junior, E. and de Oliveira e Souza, M., "A Discussion on Time Synchronization and their Effects in Distributed Cyber-Physical Control Systems," SAE Technical Paper 2016-36-0293, 2016.
Cyber-physical systems are joint instances of growing complexity and high integration of elements in the information and physical domains reaching high levels of difficulty to engineer an operate them. This happens with satellites, aircraft, automobiles, smart grids and others. Current technologies as computation, communication and control integrate those domains to communicate, synchronize and operate together. However, the integration of different domains brings new challenges and adds new issues, mainly in real time distributed control systems, beginning with time synchronization. In this paper, we present a discussion on time synchronization and their effects in distributed cyber-physical control systems. To do that, we review the literature, discuss some time synchronization techniques used in cyber-physical systems, and illustrate them via model and simulation of a system representative of the aerospace area. We also show how the time synchronization can affect the transient and stability of distributed cyber-physical control systems and we propose a way to alleviate those issues. The results obtained so far suggest that the proposed way is effective in reducing the effects of time synchronization in distributed cyber-physical control systems and we hope it will contribute to their development in the near future.