Energy-Aware Adaptive Scheduling for Battery-Less 6TiSCH Routers in Industrial Wireless Sensor Networks

Industrial Wireless Sensor Networks (IWSNs) using the 6TiSCH standard offer a scalable and cost-effective alternative to wired solutions in industrial environments, especially in hard-to-reach areas. Mains-powered devices face high installation costs and cable vulnerabilities, while battery-powered devices are limited by lifespan and maintenance challenges. Energy harvesting and supercapacitors offer promising alternatives with longer lifetimes and reduced maintenance. However, only battery-less end devices are usually considered. Due to the intermittent energy availability of battery-less devices and demanding network requirements, routers are assumed to be continuously powered. Therefore, this paper proposes, to the best of our knowledge, the first solution to integrate battery-less routers into 6TiSCH networks, building on previous work that used real-time traffic prediction models. We extend this by developing an energy consumption and storage prediction mechanism, enabling adaptive scheduling based on a node's available energy. The proposed adaptive algorithm dynamically modifies the Time Slotted Channel Hopping (TSCH) Scheduling Function to reduce the energy consumption of battery-less routers while triggering topology changes to ensure network reliability and adaptively route data based on dynamic energy availability. Evaluation of the algorithm in both small- and large-scale topologies demonstrates its effectiveness in reducing energy consumption and improving network performance by dynamically adjusting timing schedules. This approach significantly enhances the reliability and uptime of battery-less networks, although it introduces latency. Overall, the solution advances the development of fully energy-autonomous IWSNs, suitable for non-critical building automation and similar applications.