Output-Based Dynamic Event-Triggered Control for Networked Control Systems With Delays and Packet Losses Without Acknowledgements

Abstract

Event-triggered control (ETC) has been proposed in the networked control systems (NCSs) literature to reduce the need of data transmissions, and the main focus has been on the design of ETC mechanisms with a guaranteed positive minimum of inter-event time (MIET) and hence avoiding Zeno phenomena. In this paper, we propose a design of an aperiodic ETC mechanism for general nonlinear NCSs. In our setup, the communication network could introduce variable transmission delays, while data packets could get lost without acknowledgements. For this, we first introduce auxiliary variables dependent upon the transmission situations to capture the relationship between the number of successive packet dropouts, MIETs, transmission delays and the number of successful packets being transmitted. Meanwhile, by designing appropriate jump rules of these variables, the changing process of the network-induced errors can be tracked. Then, we present a novel output-based dynamic ETC strategy that can simultaneously guarantee a finite <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$L_{p}$</tex-math></inline-formula> -gain and a strictly positive lower bound despite the presence of packet losses and transmission delays. In particular, the mandatory limit of short delays can be avoided, and the transmission delays exceeding the positive MIETs are allowed. Finally, a numerical example is given to verify the correctness and effectiveness of the proposed control approach.