For decades, smart devices (i.e. wireless sensing and computing systems) have relied primarily on battery power. Yet, batteries are bulky, expensive, high-maintenance, and not sustainable for the next trillion devices. Instead of relying on energy stored in a battery, the past decade has seen new approaches enabling battery-free, energy harvesting smart devices, deployed for passive, invisible, and long-term sensing tasks. These devices compute intermittently; losing power, harvesting energy, restoring computational state, and finally continuing execution from the last checkpoint.

This new paradigm has required a rethinking of materials, hardware and software design, tool creation, and evaluation techniques. In this talk, I will discuss the broad implications of what a battery-free, trillion device IoT means, outline previous work on the topic that focused on invisible devices, and then discuss the next decade of research in intermittent computing and the battery-free IoT; devices that are user facing and interactive, devices that novices can easily program, and devices that can perform useful inference. I will present late breaking work on soil powered sensors and smart face masks, highlight a new system allowing novices to program intermittently powered devices with Python, and discuss the conception and development of the worlds first battery-free Nintendo Game Boy. 

Speaker Biography:

Josiah Hester is an Assistant Professor in the Departments of Electrical and Computer Engineering, Computer Science, Preventive Medicine, and Biomedical Engineering  at Northwestern University. Josiah joined Northwestern in Fall 2017 after completing his PhD in Computer Science at Clemson University.  He works broadly in mobile and pervasive computing, i.e. the Internet-of-Things, wireless sensor networks, and embedded systems. He specifically investigates battery-free smart devices that harvest energy from ambient sources like the sun, human action, and wireless power.

His work involves the design of computer systems that are resilient too frequent and unpredictable power failures. He works towards a sustainable future for computing and applies these techniques to mobile healthcare, infrastructure monitoring, and conservation based applications. He was named one of Popular Science’s Brilliant Ten, won the American Indian Science and Engineering Society Most Promising Scientist/Engineer Award and the 3M Non-tenured Faculty Award in 2021. His work has received a Best Paper Award and Best Paper Nomination from ACM SenSys, multiple Best Presentation and Poster Awards, and has been covered by the Wall Street Journal, The Verge, CNET, the BBC, and many others. 

Zoom Link: https://argonne.zoomgov.com/j/1618681278