SBIR-STTR Award

Harvesting Electric Power from Walking
Award last edited on: 10/30/2018

Sponsored Program
STTR
Awarding Agency
DOD : Navy
Total Award Amount
$3,191,748
Award Phase
2
Solicitation Topic Code
N06-T026
Principal Investigator
Heath Hofmann

Company Information

Lightning Packs LLC

401 School House Lane
Wayne, PA 19087
   (610) 995-2728
   lrome@lightningpacks.com
   www.lightningpacks.com

Research Institution

Penn State University

Phase I

Contract Number: N00014-06-M-0309
Start Date: 8/1/2006    Completed: 5/31/2007
Phase I year
2006
Phase I Amount
$99,999
Over the past three years, Lightning Packs LLC has invented, developed, tested, and patented the innovative Suspended-load Backpack which extracts mechanical energy from the vertical movement of carried loads and converts it to unprecedented levels of electricity during normal human walking (up to 7.4 W, about ~300-fold greater than the previously published attempts of only 20 mW). Our human testing has shown that the additional metabolic cost associated with electricity generation is kept very low due to a compensatory change in gait which reduces the metabolic power required for walking. Further, a consequence of the backpack's design is that peak dynamic forces are reduced by ~20%, making it more comfortable than normal backpacks. Initial development has begun on power electronic circuitry capable of providing the electrical power required by portable electronic devices and energy storage devices, while providing sufficient damping of the backpack mechanical dynamics for optimal ergonomics. In Phase I, we will finish the development of our innovative circuitry through the development of a custom power electronic controller which provides optimal energy harvesting from the backpack system while determining the appropriate allocation of harvested energy to the energy storage devices and portable electronic devices.

Benefits:
Commercialization Lightning Packs LLC is in an unique position to commercialize the electricity-generating backpack and provide power to the Marines and soldiers while on the move. The Suspended-load backpack was invented 2003 by Dr. Larry Rome, a Biology Professor at the University of Pennsylvania, in response to a request from the Office of Naval Research to develop a way to capture mechanical energy from human movement and convert it to electrical energy, thereby reducing the heavy loads of extra batteries carried by the Marines and soldiers. Lightning Packs was formed in 2004 by Dr. Rome specifically to commercialize the Suspended-load Backpack. The Suspended-load Backpack is a completely novel and innovative device. Accordingly, Lightning Packs received one patent with 25 claims for the electricity-generating backpack (US #6,982,497, issued on Jan 3, 2006), and has two US patents and Canadian and European patents pending for electricity-generating and ergonomic backpacks. The Lightning Packs team has also carried out extensive research over the past 2 years on the biomechanics and physiology of humans carrying loads and generating electricity with the Suspended load Backpack. Some of the results of these studies have been published in Science, while others represent proprietary intellectual property which enables Lightning Packs to predict the ergonomic effects of alterations to the design of the pack. This is a unique and crucial capability for successful commercialization. In addition, over the past 3 years, Lightning Packs has forged a close collaboration with Dr. Heath Hofmann at the Pennsylvanian State University (Penn State), who is one of the top experts in the country on energy harvesting and power electronics. His past and continuing efforts enable Lightning Packs to produce a backpack with state-of the art electronic control system which not only efficiently conditions the electricity, but controls damping of the mechanical load as well; a necessity for this device. Recognizing that solving this problem was crucial for further commercialization, Dr. Hofmann and Lighting Packs started working in advance of the solicitation and found a functional solution. Hence, we now have a clear road to commercialization as well as a demonstrable track record of our teams working effectively together. Finally, Lightning Packs has also had several groups from the Wharton School at the University of Pennsylvania analyze the market and produce a business plan. The plan presents a favorable future for commercialization. In Phase I, we will finish the development of this novel electronic circuitry, so at the beginning of Phase II we will have a good prototype for testing. In Phase II, we will pursue additional innovations and proceed to improve the ergonomics and electricity generation while reducing the weight. Improved energy harvesting will be accomplished by using more efficient generators, gearing and electronic circuitry. Reduction in weight will involve a Finite Element Analysis-driven removal of material as well as switching to lighter-weight material. We will also examine reconfiguring the components of the backpack to reduce redundant structures. Our goal will be to reduce the weight to a level which is about 2-3 lbs more than a normal backpack. As this will save carrying 15-20 lbs of batteries, and will also be more ergonomic, this presents a very attractive option to troops. Anticipated Benefits Humans have become increasingly dependent on technology, particularly electronic devices. In the past decade, electronic devices have become more mobile, enabling us to use medical, communication, computation and GPS devices, as well as sophisticated weapons systems as we move around cities, wilderness or the battlefield. At present, all of these devices run off of batteries which have limited lifetimes and add considerable weight to the device. The combination of the limited lifetimes and the large weight of batteries is particularly crucial in military applications. Soldiers must carry heavy packs (> 80 lbs), and as much as 25% of this weight is replacement batteries. Millions of dollars have gone into developing a portable and renewable energy source, however the devices currently available commercially or described in peer-reviewed journals are in the tens of milliwatt range, which is too low to be a significant solution. To solve this problem, we developed a passive device, the Suspended-Load Backpack, which extracts mechanical energy during walking and then converts up to 7.5 W of electricity. Following publication of the paper in Science, Lightning Packs received hundreds of requests for information about the backpack. In addition to military applications, the electricity generation, combined with efficient electricity storage devices, can help provide disaster-relief workers, fire fighters, forest fire fighters as well recreational hikers freedom from the heavy weight of replacement batteries, and thereby extend their abilities to operate in remote areas. This was a significant problem following the Asian Tsunami. Interestingly, field-scientists can not only use the backpack to power their GPS and instrumentation, but they can modify the mechanism to be worn by large animals, thereby permitting the animals to generate their own power, enabling radio collars to transmit physiological information indefinitely. Further, Lightning Packs has been asked to collaborate on a US Navy Project installing the mechanism on ocean reconnaissance buoys to power their instrumentation. In addition to providing people in first-world counties power while they are working off the electric grid, the energy levels generated by the backpack can have dramatic benefits for people living in developing nations. A large proportion of the population in developing countries live off the electric grid. A UN report forwarded to us by its author, spells out how major health and societal problems in remote villages can solved by small electrical sources such as from our backpack. For instance, a major health problem is contaminated drinking water-living off the grid prevents filtration. However, devices have been developed to kill bacteria with UV light which require very little electrical power (5 W for 30s (1500 J) per litre of water). Hence a small amount of electricity can provide healthful drinking water, can help provide energy for routine medical tests, and provide abilities to communicate in times of natural disaster and medical emergency. In short, finding a solution to such a universal problem as electricity generation in remote areas coupled with technological advances in low power devices, will likely solve problems that are not even anticipated today. Ergonomic Backpacks Although the driving force for the original design was to produce electrical energy, we have shown that the Suspended-load Backpack can be "retuned" to help humans with another problem, carrying around heavy loads. Based on our results, wearing the Suspended-load Backpack will reduce peak ground forces and more importantly reduce forces on the shoulder. This in turn should lead to a reduction in fatigue and orthopedic problems and may permit the carriage of greater loads. In addition, the reduction in body forces permits much faster movements, thereby making running with loads possible, a potentially important capability for rapidly responding troops. This obviously has civilian applications too. Beside recreational backpackers and runners, the extra agility is very important to first responders (e.g. firemen) and disaster relief workers who may have to travel quickly with heavy loads. In addition, it will permit endurance training of military and civilians with reduced injury. Finally, it may solve a significant public health problem of "book bag syndrome" in children, caused by young students carrying 25-40 lb backpack filled with books. By reducing dynamic loads, we predict

Phase II

Contract Number: N00014-08-C-0279
Start Date: 2/14/2008    Completed: 7/31/2013
Phase II year
2008
Phase II Amount
$3,091,749
Combat units operating on foot in remote regions are highly dependent on electrical energy for communications, navigation and sensing. As the use of electronic devices on the battlefield increases, so will the need for electrical energy independence. At present, power is provided by carrying a large weight of batteries (as much as 20 lbs), which when added to their usual 80-lb packs, represents a crushing burden resulting in reduced performance and back/joint injuries. To address this need, we previously invented and patented a device (the Suspended-load Backpack) that not only generates a large amount of electricity, but does so while reducing body forces and reducing metabolic cost. Several major roadblocks were addressed during Phase I, and the primary objective of Phase II is to ruggedize the backpack for manufacture and military deployment.

Keywords:
Electricity Harvesting, Backpack, Ergonomics, Portable Electronics