Assistant Professor Jeremy Gummeson and his Ph.D. student Noor Mohammed, both of the Electrical and Computer Engineering (ECE) Department, are members of a UMass Amherst team that has designed a charge-free, wearable device called “Shazam,” which uses the skin of the human body to charge smartwatches and other wearable devices. See Industrial Equipment News, Lab Manager, UgenceTV, The Financial, Mint Lounge, News Office release.
“The key concept that we exploit in our system Shazam is using human tissue as a transfer medium for power,” says Gummeson.
The UMass Amherst team recently received a $598,720 National Science Foundation grant, shared in collaboration with researchers from Northwestern University, to continue to develop the system’s hardware and software. Gummeson explains that the funded project involves building systems abstractions for networks of wearable devices that can exchange power and data.
Shazam came about as a result of Gummeson’s brainstorming session with Sunghoon Ivan Lee, assistant professor in the UMass Amherst College of Information and Computer Sciences and director of the Advanced Human Health Analytics Laboratory. The problem is that most smartwatches cannot monitor their wearers’ vital signs 24/7 because the watches are often being recharged at night, while the wearers sleep.
Lee and Gummeson also realized that the main reason users abandon long-term use of smartwatches is because of the inconvenience of frequent battery recharging. While brainstorming, the two scientists came up with a brilliant solution based on a well-known fact: that human skin is a conductible material.
As Lee says, “Why can’t we instrument daily objects, such as the office desk, chair, and car steering wheel, so they can seamlessly transfer power through human skin to charge up a watch or any wearable sensor while the users interact with them? Like, using human skin as a wire.”
In a paper published in the Proceedings of the ACM on Interactive Mobile, Wearable, and Ubiquitous Technologies, Lee, Gummeson, and lead author Mohammed describe the technical groundwork and showcase its feasibility.
“I am hopeful that this will open a lot of possibilities toward the development of battery-less wearable devices both for consumer and clinical applications,” Mohammed says.
Gummeson explains how the technology uses human tissue as a transfer medium for power. “In this device we have an electrode that couples to the human body, which you could think of as the red wire, if you’re thinking of a traditional battery with a pair of red and black wires,” he says.
The conventional black wire is established between two metal plates that are embedded on the wearable device and an instrumented everyday object, which becomes virtually connected via the surrounding environment when the frequency of the energy carrier signal is sufficiently high – in the hundreds of megahertz range.
As Gummeson says, “Currently, Shazam only transmits small amounts of power through the human body. And this is by design because of safety regulations that have been established by the FCC. You can think of the amount of power that gets transmitted by Shazam as roughly comparable to what’s transmitted through the human body when you stand on a body composition scale, hence poses minimal health risks.” (July 2021)