Evaluation of Decentralized Event-Triggered Control Strategies for Cyber-Physical Systems
For CPS designers, this work addresses the overlooked energy costs of sensing and listening in event-triggered control, but the results are incremental as they apply known techniques to a specific domain.
This paper proposes two MAC protocols enabling duty-cycling for sensing and actuator listening in decentralized event-triggered control, and experimentally demonstrates significant system lifetime extension over periodic control in a smart water network testbed.
Energy constraint long-range wireless sensor/ actuator based solutions are theoretically the perfect choice to support the next generation of city-scale cyber-physical systems. Traditional systems adopt periodic control which increases network congestion and actuations while burdens the energy consumption. Recent control theory studies overcome these problems by introducing aperiodic strategies, such as event trigger control. In spite of the potential savings, these strategies assume actuator continuous listening while ignoring the sensing energy costs. In this paper, we fill this gap, by enabling sensing and actuator listening duty-cycling and proposing two innovative MAC protocols for three decentralized event trigger control approaches. A laboratory experimental testbed, which emulates a smart water network, was modelled and extended to evaluate the impact of system parameters and the performance of each approach. Experimental results reveal the predominance of the decentralized event-triggered control against the classic periodic control either in terms of communication or actuation by promising significant system lifetime extension.