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Building a Better Bike Helmet Out of Paper
An anonymous reader writes "Inspired by nature, a London man believes the solution to safer bike helmets is to build them out of paper. '"The animal that stood out was the woodpecker. It pecks at about ten times per second and every time it pecks it sustains the same amount of force as us crashing at 50 miles per hour," says Surabhi. "It's the only bird in the world where the skull and the beak are completely disjointed, and there's a soft corrugated cartilage in the middle that absorbs all the impact and stops it from getting a headache." In order to mimic the woodpecker's crumple zone, Anirudha turned to a cheap and easily accessible source — paper. He engineered it into a double-layer of honeycomb that could then be cut and constructed into a functioning helmet. "What you end up with is with tiny little airbags throughout the helmet," he says.'"
Although the article didn't make it explicit, I'm assuming that the helmet gets a coat of resin or something to water-proof it. Speaking for myself, I don't need rain to get a helmet wet -- I don't have great strength, endurance, or aerobic capacity, but I sweat like a champ.
if you bother to read the article, you would learn it absorbs far more of energy. They state that a 15mph crash can subject the brain to 220G of force wearing a polystyrene helmet. Using the paper helmet, the test units brain-analogue was subjected to a mere 70G of force. This was tested in Europe, where regulations state for a helmet to be approved, the brain may not be subjected to more than 300G of force at 15mph. So a significant improvement over traditional polystyrene helmets, in terms of energy absorption and dissipation. I posit that this is most likely due to the fact that paper does not recoil back to its original form as much as the polystyrene.
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
There are actually helmets designed to reduce the rotational forces though. For example, I remember my own university trumpeting one helmet design in which a kind of inner helmet was allowed to slide inside an outer helmet on a low-friction liner. Simulations demonstrated a reduction maximum strain forces on the brain. There's a presentation on it here by the company which now manufactures them: http://mipshelmet.com/how-it-works/the_invention and since it's a simple design I suspect that it will be a component of the helmet of the future.
However, honeycombs make excellent single-use shock absorbers, so those surely have a place in helmets as well.
Even if the site you link to were reasonable there is every reason to believe that helmets can be made truly excellent and made to give incredible protection both against shocks and rotational forces.
Responding to oneself is generally bad form, but:
http://www.badscience.net/wp-content/uploads/Screenshot-2013-12-13-17.12.05.png
In summary (and partially concordant with the person I initially criticised): On a community-wide level, requiring people wear helmets may not reduce head injuries, but on an individual level if you are cycling and can add a helmet to your cycling without changing your behaviour, you are probably safer with the helmet.
(This requires a bit of reading into the paper, and a couple of assumptions: Assumptions are: drivers don't suddenly start being dickheads around you because you're wearing a helmet, and you don't start being a dickhead because you put on a helmet. If those two hold, then the case-control rather than community-wide studies are more applicable to the individual choosing whether or not to wear a helmet).