Project Description

Ventricular assist device (VAD) therapy has significantly improved patient outcomes by technological innovations based on smaller, frictionless, single moving part pumps that have overcome the failures associated with earlier larger and more complicated models. However, the continued presence of drive-lines (which are the wires that exit the body) undermines the full potential these newer VADs can offer. Drive-lines are well recognized as a source for infection, increased morbidity, re-hospitalizations, and limit the movement that patients demand and deserve. Older, inductive based technologies used for wireless power are hampered by a short range of a few millimeters, alignment issues, and poor efficiency.

Our team is developing the Free-range Resonant Electrical Energy Delivery (FREE-D) wireless power system which uses coupled resonators to efficiently transfer power over meter distances. Previous work has shown the successful application of the FREE-D system to wirelessly power an axial VAD at upwards of 80% efficiency. The power was delivered over a one meter distance without interruptions or fluctuations with coil, rectifier and regulator efficiency over 80% and overall system efficiency of 54%. The next steps in the research include refining the FREE-D system for animal trials. This will require a biocompatible enclosure that will allow efficient transfer of wireless power from the external transmitter to the implanted receiver.




Sezai Innovation Award, for "Promise of unrestricted mobility and freedom with wireless powering of a Ventricular Assist Device (VAD)," at the 19th congress of the International Society of Rotary Blood Pumps, Louisville, KY September 8th to 10th, 2011.

Willem Kolff/Donald B. Olsen Award, for most promising research in the development of artificial hearts, for paper “Innovative Free-Range Resonant Electrical Energy Delivery System (FREE‐D System) for a Ventricular Assist Device Using Wireless Power,” presented at American Society forArtificial Internal Organs (ASAIO), June 2011.

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Wireless Resonant Energy Link (WREL)

This project explores the use of magnetically coupled resonators to safely deliver 10s-100s of watts of power wirelessly to receivers. Our key contribution is the development of adaptive tuning techniques that enable near constant power transfer efficiency, as a function of varying transmitter-to-receiver range and orientation as well as changes in the loads power consumption.

6 Papers
3+ Video
2 Tech Transfer
7 Featured Press


This project orginated in the Sensor Systems Lab led by Joshua Smith at the University of Washington.