Today’s military soldiers shoulder quite a burden of gear when in the field, often up to a 150 lbs., about 1/5th of which stems from spare batteries used to power night-vision devices, radios and other equipment.
To lighten soldiers’ loads and lessen patrol fatigue, Army researchers are testing a backpack that generates electricity through the energy of human locomotion.
According to the Army Research Laboratory, the prototype energy harvesting backpack adds a two-spring frame to a standard assault pack that gently glides up and down as the soldier walks or runs, generating power from the motion that recharges a soldier’s battery. The frame also holds the pack in a controlled motion when the soldier runs, thus reducing fatigue while on a mission.
WHAT IS ENERGY HARVESTING?
“Energy harvesting is a process that captures small amounts of energy from ambient energy sources such as solar, thermal, wind, and mechanical, and accumulating them and storing them for later use,” says BCC Research analyst Shalini R. “While energy is available in numerous forms and sources, electrical energy is the form that drives the majority of today’s operations, applications and devices. Electrical energy can be generated, stored, transmitted, and managed better than any other form of energy. The principle objective of employing energy harvesters is to efficiently utilize existing energy sources that would otherwise be lost,” she adds.
Larry Rome, a muscle physiology expert and professor of physiology at the University of Pennsylvania, developed the backpack’s core technology in 2005. His company, Lightning Packs, LLC, has partnered with the U.S. Army Communications-Electronics Research, Development and Engineering Center, on the design of the backpack.
Eventually, the company hopes the technology will benefit and potentially save the lives of field scientists, hikers, explorers, soldiers and disaster workers, who can produce their own electricity out in the field.
The technology behind applications like the energy harvesting backpack are driving growth in the global market for energy harvesting, notes Shalini R. “One of the key challenges faced by the market is that many of these devices work in challenging environments, and this obstacle must be addressed. In short, energy harvesting is driven by energy crisis management and an increasing number of new applications.”
She adds that the technology side of the market has enjoyed gains been made both through the improvement of existing technologies and development of new ones. “On the application side,” she says, “the industry faces the challenge of developing applications that require the availability of uninterrupted power to devices with limited form factors over extended durations.”
Other military researchers are investigating the energy harvesting backpack, as well. Last September, the Naval Surface Warfare Center Dahlgren Division (NSWCDD) partnered with U.S. Army agencies at Natick Soldier Research and Development Center (NSRDEC) to try and meet that challenge. The partnership conducted a 12-mile road march using a U.S. Army Ranger team to evaluate the electricity generating backpack.
The partnership intends to increase the electrical sustainability of dismounted infantry in hard to reach austere environments, according to the NSWCDD. The goal is to allow marines and soldiers to operate farther, longer, and lighter with less spare batteries and logistical re-supply. The empirical data and qualitative feedback from that march will be used to improve functional and ergonomic human factors aspects of the pack.
As for the ARL, it has tested the backpack only on about 12 Army civilians and contractors. It intends to publish its findings after 20 people are tested, according to Kevin McCaney.