Paper to protect!
Discussion
http://www.bbc.co.uk/news/health-25681895
"If you crash at 15 miles per hour in a normal helmet, your head will be subjected to around 220G [G-force], whereas the new design absorbs more of the impact and means you experience around 70G instead," says Surabhi.
Anyone going to cross over to paper?
"If you crash at 15 miles per hour in a normal helmet, your head will be subjected to around 220G [G-force], whereas the new design absorbs more of the impact and means you experience around 70G instead," says Surabhi.
Anyone going to cross over to paper?
garrykiller said:
one spat of rain and you would have a soggy mess on your head.
I assume it's made from more than a used box from the back of Tesco. I'd have no problem using one, after all polystyrene hardly screams "total protection" it's just meant to destroy itself to absorb energy.
Having seen one, the paper is impregnated with something. I wouldn't worry about moisture.
However, I smell a lot of hyperbole here. The acceleration experienced is a function of how much velocity change you experience over the given amount of time. If you want a lower acceleration, you need to make more distance, and hence time for that to happen. (and a bigger helmet)
Back of envelope calcs suggest a stopping time from 15mph-0mph of .003sec at 220g, or .01 sec at 70g
My memory of distance travelled gets a bit sketchy, but I'm coming out with 1cm at 220g, or 30+cm at 70g (possibly 40+, depending on method, but that doesn't feel right)
That's a lot more helmet, but frankly it's a bit arbitrary as we/they are assuming a direct, sudden stop to zero, rather than glancing blows etc., helmet design is a lot more complicated than that... anyway!!
Most helmets are not solid polystyrene. I have to think that you could engineer whatever rate of deceleration you like with either material. What your head experiences will be a result of the helmet design, rather than material choice. Or, to put it in a more graphic sense, cardboard edge on is quite hard. Land on a small piece of polystyrene and you'll crush it easily. All in how you use it.
Erm.. as you were
Short version, sure they'll be perfectly good helmets. Don't believe protection is a materials issue, simply design. Maybe they can build lighter for the same protection with a different material, I'll stick with what I've got for now.
However, I smell a lot of hyperbole here. The acceleration experienced is a function of how much velocity change you experience over the given amount of time. If you want a lower acceleration, you need to make more distance, and hence time for that to happen. (and a bigger helmet)
Back of envelope calcs suggest a stopping time from 15mph-0mph of .003sec at 220g, or .01 sec at 70g
My memory of distance travelled gets a bit sketchy, but I'm coming out with 1cm at 220g, or 30+cm at 70g (possibly 40+, depending on method, but that doesn't feel right)
That's a lot more helmet, but frankly it's a bit arbitrary as we/they are assuming a direct, sudden stop to zero, rather than glancing blows etc., helmet design is a lot more complicated than that... anyway!!
Most helmets are not solid polystyrene. I have to think that you could engineer whatever rate of deceleration you like with either material. What your head experiences will be a result of the helmet design, rather than material choice. Or, to put it in a more graphic sense, cardboard edge on is quite hard. Land on a small piece of polystyrene and you'll crush it easily. All in how you use it.
Erm.. as you were
Short version, sure they'll be perfectly good helmets. Don't believe protection is a materials issue, simply design. Maybe they can build lighter for the same protection with a different material, I'll stick with what I've got for now.upsidedownmark said:
Good stuff and
Erm.. as you were
Short version, sure they'll be perfectly good helmets. Don't believe protection is a materials issue, simply design. Maybe they can build lighter for the same protection with a different material, I'll stick with what I've got for now.
Petty much my thoughts too.Erm.. as you were
Short version, sure they'll be perfectly good helmets. Don't believe protection is a materials issue, simply design. Maybe they can build lighter for the same protection with a different material, I'll stick with what I've got for now.Gassing Station | Pedal Powered | Top of Page | What's New | My Stuff


