IEEE Transactions on Automatic Control, Vol.65, No.10, 4324-4331, 2020
Energy-Efficient Time-Triggered Communication Policies for Wireless Networked Control Systems
Energy-efficient communication protocols have become an important topic over the past two decades due to environmental issues, increased monetary costs of energy consumption, and limited battery capacities of sensors and mobile devices. In this context, we present a novel approach to design energy-efficient time-triggered communication policies for wireless networked control systems, while ensuring a given control performance. We consider a plant, modeled as a deterministic discrete-time linear system, which is controlled through a wireless network by an output-feedback law. We proceed by emulation, i.e., we construct the controller to stabilize the origin of the plant while ignoring communication constraints. Next, the wireless network is taken into account and we assume that the probability of packet drops depends on the transmission signal power. We introduce the notion of stochastic allowable transmission interval (SATI) to characterize stabilizing time-triggered transmission policies. We then explain how to minimize the average energy expenditure of the transmitting devices while satisfying the SATI constraints, thus ensuring the control requirements. Simulations results are provided to illustrate the tradeoff between the communication and the control costs.
Keywords:Wireless networks;Wireless sensor networks;Stochastic processes;Networked control systems;Capacitive sensors;Energy-efficient communication;networked control systems;stochastic systems