The Wireless Control Bus: Enabling Efficient Multi-hop Event-Triggered Control with Concurrent Transmissions

TL;DR

This paper introduces the Wireless Control Bus (WCB), a network stack that enables efficient, reliable, and low-latency multi-hop wireless event-triggered control, demonstrating significant energy savings and practical viability in cyber-physical systems.

Contribution

The paper presents WCB, a novel wireless network stack that supports event-triggered control with low overhead and high reliability in multi-hop wireless networks.

Findings

WCB achieves same control quality at reduced energy costs.

WCB supports timely and reliable sensor and actuator communication.

Demonstrated effectiveness on a water distribution system testbed.

Abstract

Event-triggered control (ETC) holds the potential to significantly improve the efficiency of wireless networked control systems. Unfortunately, its real-world impact has hitherto been hampered by the lack of a network stack able to transfer its benefits from theory to practice specifically by supporting the latency and reliability requirements of the aperiodic communication ETC induces. This is precisely the contribution of this paper. Our Wireless Control Bus (WCB) exploits carefully orchestrated network-wide floods of concurrent transmissions to minimize overhead during quiescent, steady-state periods, and ensures timely and reliable collection of sensor readings and dissemination of actuation commands when an ETC triggering condition is violated. Using a cyber-physical testbed emulating a water distribution system controlled over a real-world multi-hop wireless network, we show that ETC over WCB achieves the same quality of periodic control at a fraction of the energy costs, therefore unleashing and concretely demonstrating its full potential for the first time.