Date of Award
Doctor of Philosophy (PhD)
Wireless battery-free and energy-harvesting devices are expanding the reach and vision of the Internet of Things, where trillions of embedded computational things interconnect ubiquitously around us and inform many different aspects of our everyday lives. Designing these systems without batteries and interconnecting wires lowers maintenance, environmental, and economic costs while also extending device lifetime and deployment opportunities. Over the last decade, research on these ultra-low-power embedded sensors and systems has dramatically increased — enabling new and exciting prospects in many different scientific fields, from smart building and health monitoring applications to animal and activity tracking.
These systems are not without their challenges, however, relying on developers to not only manage core system functionality, but also to optimize very limited storage, energy, and computational ability. Previous work in this space focused primarily on getting basic functionality working on harvested and sometimes intermittent power. Application development for ultra-low-power and/or intermittent embedded systems is particularly difficult — each design choice can directly impact the overall performance of a system. Developers must juggle resource limitations, overcome problems caused by errors and outages, predict possible future resource availability, and still design reliable systems and their applications. To make way for the next generation of ultra-low-power computational things to be deployed all around us, we must advance the tools, information, and resources available to ease the burden on developers and designers in this space.
This dissertation furthers the application reach of the next generation of ultra-low-power computational things by providing developers with new techniques for making these devices more resilient to outages and errors, demonstrating new ways to design sensors more sustainably by sensing in unconventional ways, and exploring performance tradeoffs when securing the data our devices collect. We present a few techniques to assist in time estimation over outages and to help maintain wireless re-programmability in the presence of immobilizing software errors to increase the resiliency of deployable systems. We also explore the use of harvesters as unconventional low-cost sensors to make our devices all the more sustainable, even beyond removing batteries. We deploy this in a case study to demonstrate this type of unconventional sensing in a novel way for detecting room-level occupancy in a building using only reflected ambient light. Finally, we present an exploratory evaluation of the performance tradeoffs developers may encounter when adding security to their system applications under tight resource constraints. These solutions create new tools and insight for ultra-low-power and batteryless systems developers to use and refer to when designing the ultra-low-power computational things of our connected tomorrow.
Tobias, Nicole, "Resilient, Sustainable, and Secure Systems Support for Ultra-Low-Power Computational Things" (2023). All Dissertations. 3515.
Author ORCID Identifier
Available for download on Tuesday, December 31, 2024
Computer and Systems Architecture Commons, Hardware Systems Commons, Information Security Commons, Power and Energy Commons, Signal Processing Commons, Systems and Communications Commons, Systems Architecture Commons, VLSI and Circuits, Embedded and Hardware Systems Commons