Seminar: Vaishnavi Ranganathan

Vaishnavi Ranganathan
“Ubiquitous On-Body and Implanted Sensing”
Friday, April 27, 10:00 am
Larsen 239


The vision of an Internet of Biomedical Things is catalyzing the development of smart wearable sensor technology for continuous physiological monitoring in natural environments, outside of hospitals. Such an infrastructure can enable faster detection and treatment of chronic diseases that currently go unnoticed until their final stages. Availability of on-body and implanted sensing will also facilitate monitoring of medical conditions like epilepsy to prevent the onset of seizures or to empower paralyzed people to perform functional tasks. Most importantly, it helps create a widespread awareness of health conditions and supports the growth of fundamental knowledge about the human body functions to enable better healthcare.

A key barrier to realizing the Internet of Biomedical Things is power. Batteries are costly in volume, weight, cost and lifetime. Replacing them can require surgery in the worst case, and even in the best case recharging them usually requires downtime. Techniques to reduce power requirements and facilitate charging of implanted device will help make the Internet of Biological Things a reality.

In this talk I will highlight my research contributions in this domain, which include developing battery-free wireless technology for implantable and wearable devices. Specifically, the heart of my research lies between the two following areas. The first area is development of a “Brain-Computer-Spinal Interface,” a wireless neural recording/stimulation interface. The application drive for this work is treatment and rehabilitation for patients with limb paralysis due to spinal-cord injury. The second area is building battery-free sensing platforms that harvest RF energy to perform on-body sensing. Towards this I’ll present one of my recent works on developing a passive analog sensing platform – the “RF Bandaid.” Both these devices leverage wireless energy harvesting and use ultralow-power backscatter communication for wireless data transfer. Together they fuel my mission for the field: to develop low-power sensing interfaces, enable new sensor technology development and support pervasive and accessible low-cost medical sensing.


Vaishnavi Ranganathan is currently pursuing her PhD as a Washington Research Foundation fellow in the Sensor Systems laboratory at the University of Washington, Seattle. She is also an engineering consultant for the Microsoft Research, Next Medical Devices Group. Her research interests include ubiquitous biomedical devices, wireless power transfer and brain-computer interface applications. She is a member of the Center for Sensorimotor Neural Engineering (CSNE) an NSF-funded Engineering Research Center (ERC) and her graduate work has also been funded by the Paul G. Allen Family Foundation. She received a B.Tech degree in Electronics and Instrumentation Engineering from Amrita University, India, in 2011, and a M.S degree in Electrical Engineering, specializing in NEMS, from Case Western Reserve University, Cleveland, OH, in 2013. She also worked as an undergraduate researcher in the Nanobios lab at Indian Institute of Technology, Mumbai, India, where her focus was MEMS for biomedical sensors.