Biomechanics and Backpacks: The Solution
We go solution hunting in this follow up post…
Our first post in this short Biomechanics and Backpacks series outlined the problem faced by numerous backpack users around the globe – that of restricted body movement while wearing a pack.
Well folks, it’s time to get more excited than a Mexican jumping bean on a sugar high because Johannes Flem and the Bergans design team have a solution to this frustrating problem.
We let Johannes pick up the discussion again…
Johannes: A long night of some serious caffeine buzzing resulted in the above sketch for a pack that allows extensive freedom of movement. The backpack addresses the movement problem in the following manner:
A backpack does not provide much flexibility when fully loaded, so the Bergans pack incorporates a hip belt and shoulder straps that are connected to the pack via a helical-shaped spring steel frame. This frame is bent to create a shoulder segment, center segment and hip segment. The center segment is the only one attached to the backpack; therefore the shoulder and hip segments have independent freedom of movement.
The key to this spring steel frame is the fact that it bends (in a similar manner to the way that your spine bends), as opposed to rotating. The frame allows the shoulder and hip segments to twist, while also providing shock absorption. In addition, it is capable of extending if the pack wearer bends forward and it has the ability to center itself. Another advantage of this frame is its construction, with no components such as hinges, bolts, stays and the like that are subject to wear and tear.
Not content with a mere caffeine-crazed carry creation sketch, we constructed a rough prototype of the pack the next day. With 20 kgs of weight loaded, it was time for a full day of traipsing around in the woods. Did it work, you ask? It worked so well that the design was patented within a month of its creation.
Now you may be thinking, well this backpack must be the designer’s darling and there’s bound to be some biased thinking here. However, subsequent prototypes have ventured as far as the Himalayas and across Scandinavia, with no complaints at all. The following photos show the pack being used above the Arctic Circle (around midnight!).
The photo below displays the pack from the front and the back, with the shoulder, hip and center segments clearly visible. The spring steel frame travels along the edges of the gray pads and is anchored to the pack solely via the center segment. However the other two segments have limiting webbing which prevents extreme movements.
Words and images can give you a sense of this pack, but there’s nothing like a test carry to get a real feel for it. If you’re heading to the Outdoor show in Friedrichshafen this summer, visit the Bergans booth at A5-301. It’s the perfect opportunity to find out more about this pack and to try it out for yourself.
Johannes Flem – Bergans design team