A Hardware Platform for Separating Energy Concerns in Tiny, Intermittently-Powered Sensors

Energy harvesting is an indispensable mechanism of sensor devices that operate in perpetuity. While harvesting free energy from the environment has enabled many applications, it has also spawned new problems, and new paradigms. Notably, making decisions on when to use high power sensors and external components when energy is scarce, and future supply is unpredictable. Because sensor nodes generally share a single, centralized energy store, seemingly atomic, or unrelated sensing tasks can hamper each other by drawing the supply voltage too low, and draining the energy reservoir. This demonstration presents the United Federation of Peripherals (UFoP), a novel method of separating energy concerns in hardware by allocating dedicated energy storage (in the form of small capacitors) to specific sensor components, and charging them in a prioritized fashion with an analog front end. UFoP gives application designers a more deterministic view of energy and task scheduling, allowing them to make better informed decisions when developing sensor applications. Designers do not have to rely on crude estimates or simulations but can instead depend on in-situ analog measurements to opportunistically drive their applications.