Scientists have figured out how to tap into the inner motion in a backpack when you walk, in order to generate electricity.
Details about the project have been printed in the journal Royal Society Open Science.
How Does It Work?
Imagine a pendulum that has been mounted to the frame of a backpack and then stabilized with springs, the weight of the backpack is securely attached to the pendulum. When that pendulum swings from side to side as you walk then the gears can use that swinging motion to drive a generator which in-turn charges a battery.
Common suggestions on avoiding back pain and wearing a backpack securely, often include warnings that you shouldn't let the backpack swing from side to side as this can potentially negatively impact posture. However, in this case the swinging motion works out for your benefit in other ways.
Saving Energy
Scientists discovered, while volunteers walked with the pack on a treadmill, that the heavy load didn't significantly impact their metabolic rate as well, compared to when they were carrying a pack that was in a fixed place. The backpack was seen to reduce the forces of acceleration that would come with a regular pack and therefore researchers assume that people might be able to enjoy a more comfortable, longer hike because of it.
Interestingly, researchers have also previously asserted in earlier studies, that walking on a swaying surface can also help to save energy, roughly 5 percent more than walking on a stationary surface.
The energy-harvesting backpack that they've created weighs about 5 pounds and would need to weigh significantly less if it were to ever be considered a true competitor as an alternative to batteries on the market today.
This isn't the first time that researchers have come up with this idea, they've been working on backpacks that have the ability to generate electricity for years now.
Some prototypes for this idea have already tried to raise funds on platforms like Kickstarter, in an effort to help them come to market. One of those ideas, known as Lightning Packs, has received an award for their innovation, which has given soldiers the ability to generate electricity as they operate in the field, reducing the need for them to carry batteries and freeing up that space for other valuable resources in their bags.
Lightning Packs is also now working on raising funds to create their HoverGlide design, which will be a backpack that floats and helps reduce the impact forces of running or walking by more than 80 percent.
