SBIR Phase I: Prototype for Vibration Harvesting in Wearables

The broader impact/commercial impacts of this Small Business Innovation Research (SBIR) Phase I project will be in enabling human movement vibrations to be used to power commercial applications such as wearable devices. The end goal is a wearable, such as a heart rate monitor for athletes, that would never need a coin cell battery replacement or a recharge. Such a wearable product would enable continuous data acquisition, allowing better monitoring of an athlete’s performance. This technology would limit the use of coin cell batteries. Once an initial market of wearables for athletes can be commercialized, longer-term wearable applications in telehealth and national defense will open up. Key innovations will enhance scientific and technological understanding in the power management circuitry for a system powered by human movement and in the long-term use vibrations harvesters. A business model first focused on creating a prototype wearable for athletes will rely on technological advances in chip circuit design and mechanical energy harvesters. This Small Business Innovation Research (SBIR) Phase I project addresses the challenge of building a low-power energy harvesting system to harvest vibrations from human movement. Electromagnetic vibration harvesters are ideal for harvesting low-frequency human movement. Unlike piezoelectric harvesters’ high voltage outputs, electromagnetic harvesters’ voltage outputs are low and will not create an electrostatic discharge event. This allows the use of low-power innovations in integrated circuit Complementary Metal Oxide Semiconductor (CMOS) technology. Unique circuit designs allowing for low-voltage start-up, a custom electromagnetic vibration harvester, and power-management system are necessary for a prototype system that will need to operate from non-periodic human movement in this project. An electromagnetic harvester and discrete power-management system will be built using a pre-existing integrated circuit-based low-voltage start method. New techniques will be developed for the power-management system for non-periodic harvested human movement. To accomplish this, both the harvester and prototype containing the harvester and electronics will be built and tested on a shaker table using human-based acceleration profiles. The final prototype will be shown to store at least 75µW in this testing. The anticipated prototype will be able to charge a rechargeable battery that will power a sensor. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.