Friday, May 11, 2012

Army scientists explore wireless power transfer

The American Soldier is equipped with more capabilities than ever before. These capabilities come in the form of new and more powerful devices that translate to a need for more power.

Currently, power is supplied to the dismounted Soldier through a collection of batteries, many of them rechargeable. A focus of Army Science and Technology is to figure out how to power the Soldier, and to enable all of his/her new capabilities, without increasing (and ideally decreasing) his/her physical load.

In order to accomplish this imperative, the U.S. Army is exploring a variety of different technologies and concepts. One exciting technology that opens up different concepts of powering the Soldier is the wireless transfer of power. The U.S. Army is allocating $5-$6M to advance these technologies.

Wireless power could eliminate the need for bulky cables, especially between the Soldier's helmet and vest (where centralized power sources might reside). Wireless power also allows for the recharging of Soldier gear whenever the Soldier enters a "recharging zone," to include a vehicle, certain areas within a forward operating base, etc.

The U.S. Army funds the Institute for Soldier Nanotechnology,or ISN, at the Massachusetts Institute of Technology, known as MIT, in Cambridge, Mass. One of the many discoveries at the ISN is the invention and development of strongly coupled magnetic resonators that can transfer electrical power over (relatively) large distances.

Scientists and engineers at the U.S. Army's Natick Soldier Research Development and Engineering Center, or NSRDEC, in Natick, Mass., have picked up this concept and worked with the company founded by ISN technology developers, as well as its competitors, to design systems that can wirelessly transfer power between the Soldier helmet and the Soldier vest.

Current capabilities allow for using a Soldier battery (Li-145) on the vest or torso to transmit ~5W of power to a helmet receiver at about 50 percent efficiency. Current programs are in place to increase that efficiency. As might be expected, the shorter the distance required for power transfer, the more efficient the transfer process.

The U.S. Army is also leveraging work performed by the Defense Advanced Research Projects Agency. One effort of note explores the simultaneous wireless recharging of multiple items. The U.S. Army's Tank and Automotive Research Development and Engineering Center, known as TARDEC, in Warren, Mich., and Communications Electronics Research Development and Engineering Center, or CERDEC, in Aberdeen, MD, are both expanding on this (and alternative) technologies to increase the efficiency of power transfer over longer distances (50ft) so that Soldier recharging from vehicles and recharging from areas within a forward operating base can become realities.

The concept is to develop a future interoperable system so that organic Soldier equipment recharging can reduce both the cognitive and physical load on the dismounted Soldier.