Symbolic Abstractions of Networked Control Systems

The last decade has witnessed significant attention on networked control systems (NCSs) due to their ubiquitous presence in industrial applications, and in the particular case of wireless NCSs, because of their architectural flexibility and low installation and maintenance costs. In wireless NCSs, the communication between sensors, controllers, and actuators is supported by a communication channel that is likely to introduce variable communication delays, packet losses, limited bandwidth, and other practical nonidealities leading to numerous technical challenges. Although stability properties of NCSs have been investigated extensively in the literature, results for NCSs under more complex and general objectives, and, in particular, results dealing with verification or controller synthesis for logical specifications, are much more limited. This paper investigates how to address such complex objectives by constructively deriving symbolic models of NCSs, while encompassing the mentioned network nonidealities. The obtained abstracted (symbolic) models can then be employed to synthesize hybrid controllers enforcing rich logical specifications over the concrete NCS models. Examples of such general specifications include properties expressed as formulas in linear temporal logic or as automata on infinite strings. We thus provide a general synthesis framework that can be flexibly adapted to a number of NCS setups. We illustrate the effectiveness of the results over some case studies.