Wear your helmet kids!

I've not read all the arguments here, but on this occasion, from the evidence in those pictures, I don't think that helmet will have absorbed much force. I thought that even before reading TJ's comments. The helmets structural integrity has failed, rather than compressing.

Its difficult to tell from the pictures whether the interior is crushed, and if it is, it must only be slightly.

Thats not to say is hasn't been of any use, since it clearly must have absorbed some force, although this would have been after peak impact.

I'm still pro helmet though, if only for all the general bumps and scrapes and low hanging branches.

How about a helmet that you fill with water. Can be quite good at dissipating forces, just top it up after a crash!

LHS, are you saying that helmets shoudl be replaced every time they are dropped onto the floor from your hands? 😕 This happens quite a lot for me…

Scienceofficer – if you had read all the thread, you'd have read the expertise posted therein, saying that although it doesn't look like the EPS has compressed much, it probably has, and that little compression can be enough to dissipate enough energy to save brain injury.

anyone who drops there helmet and thinks it will be ok, think again, you potentially will have lost the majority of the impact protection due to the EPS already being compressed…

Sat at the weekend watching a couple of kids unloading their gear from a car. The helmets came out of the boot, and were promptly thrown 4 yards onto tarmac.

The theoretical protection offered by a helmet of a particualr design, and the actual protection offered by many helmets must be very different. I've no idea how long I was riding around in my last road helmet with a bloody great crack in it. I'd just got out of the habit of checking it over… 🙂

I would expect that most manufs might consider it too much to try to develop in an alternative direction.

The question really is do they need too? A bike helmet offers a consistent level of protection around the circumference of the head. Certainly with Mountain Biking I would assume that the point of impact in an accident could be anywhere.

One thing that they may want to consider is protection around the ears, a large proportion of cycling injuries involve ears being torn as the helmet does a good job of protecting the skull but leaves the ear area exposed. The question the manufacturer would raise is would people want this style of helmet? Weight, look, cooling etc.

Why can't we have some indicators built in that show clearly when certain portions are irrepairably damaged.

Indicators can very easily be built into outer shells of helmets. Again, with additional cost involved.

Also would a more modular helmet be possible I wonder? So you could replace the bits that are damaged.

Anything is feasibly possible, but again down to cost. Modular style helmets tend to be designed more for comfort and fit issues and frangible elements rathr than for replacement of damaged parts. A main design consideration for all helmet manufacturers is that in the case of accidental damage, the helmet is replaced. Modular designs would have to be coupled with indicators as you would not be able to know whether adjacent modules had been affected or not.

LHS, are you saying that helmets shoudl be replaced every time they are dropped onto the floor from your hands?

To preserve the intended level of protection, yes.

crikey – Member
Judging from this discussion, helmet compulsion is only a couple of years away. Then legal disclaimers for riding on owned land, then bike bans as in some towns in the states…

Hysterical, much…

I see TJ's point about helmets increasing the rotational forces. I'm just struggling to see a way of making a helmet that keeps the head the same size or even reduces it :/

Its not just the increase in size – its the way the helmet interacts with the ground. With an unhelmeted head your scalp moves against the skull effectively lubricating the skull/ ground junction. A helmet doesn't and sticky out bit may grab.

Hence the POC helmet (and one other motorcycle helmet) that now have layers built in to act like your scalp does

The results of the rotational accelerations are a much worse brain injury that you get from impacts.

This has been show both experimentally and from retrospective studies but how significant is still debatable. Some studies show this effect actually making injuries worse in 30+% of serious accidents ( but I believe that is an overestimate)

Its a factor that is not taken into account in the research like the BMJ survey LHS quoted Again an area where I would like to see a lot more research.

LHS – Member

One thing that they may want to consider is protection around the ears, a large proportion of cycling injuries involve ears being torn as the helmet does a good job of protecting the skull but leaves the ear area exposed.

I would like to see helmets that came much lower on the head – covering the ears and the back of the head more – like many ski helmets do. Heat is the issue here really as well as fashion ? acceptability I guess.

Is a more effective helmet that is only worn for downhills better than a less effective helmet worn for climbs as well?

To preserve the intended level of protection, yes.

That could get expensive 🙁

covering the ears and the back of the head more

Looked at the Xen? Also, you have the option of pisspots ie jump/BMX style lids.

That could get expensive

Yes, and imagine if it was a Flight helmet worth 10's of 1000's of £'s!

Even if I was convinced that wearing a helmet was no safer than not, I still would! The psychology of 'feeling' safe and therefore giving me more confidence means that I'm likely to ride less tentatively, and therefore more committed, and so probably less likely overall to come off.

FWIW, I've never fallen on my head whilst biking, but I did split a helmet when a car hit me and I landed on my head on my way home from work.

A good designer (the bow tie boys) could turn an ugly foam-fest into an acceptable looking helmet, I bet.

I would add to the modular thing, that a multi part assembly for a helmet would introduce more complexity and I would then question the crash performance of each joint between the modules in addition to the performance of the whole assembly/helmet.

I agree with LHS and TJ, as far as I don't think it would be a waist of time to increase coverage. Combined with good duct design I think one could see more of the head covered, a larger contact area head to EPS, ducting included.

But as we know, Manuf costs will go up and I reckon ole Joe-Public isn't going to shell-out £800 on 4 helmets (him, her and two kids)

While CFRP may be too expensive for the cycle helmet, I'd be surprized if another material couldn't be found.

Also perhaps a removeable liner of a soft foam, a few mm thick to go between head and EPS ?.

Another is straps anchored on the sides of the helmet, rather than being linked over the head, under/through the EPS ?.

Well, one thing I think I can see here is that while a lot of us buy and wear current design helmets, doesn't particularly mean that we've reached the Apex of helmet design for crash protection.

Yet.

Definite on the wear your helmets.

Just came off a few scrapes and bruises, but I knocked my head hard enough on a tree root to daze me for a few seconds and feel it for half an hour afterwards.

No helmet, I imagine the dazing would have been a lot worse

Another is straps anchored on the sides of the helmet, rather than being linked over the head, under/through the EPS ?.

A lot of helmets are already made like this. It's nice, cost they stand off your head a bit more and are hence more comfortable.

Couple of interesting ideas here
http://inhabitat.com/2010/07/15/new-helmet-for-skiers-and-snowboarders-scans-for-brain-injuries/

http://flipside.theiet.org/blog/cardboardhelmet.cfm

ooOOoo.

Interesting. Looks like an egg-box style foam pattern, by what I can see through the holes in the top of the helmet.

Not enough coverage though, imo. But then again, looks like a prototype.

Strap anchored to the outer shell too.

🙂

Solo

your scalp moves against the skull effectively lubricating the skull/ ground junction

That really did make me throw up in my mouth! 😥

All the helmets I've had have reduced my injury (they won't stop a lorry sure) but for small bangs that would create havoc have resulted in a bump max. Helmets can reduce injury and I have smashed 4 helemts with 2 cracks and 2 smashed to bits from head trauma. One old helmet in the 90s stuck out more than my nose when I headbutted the ground, my head bounced back up. Try head butting tarmac with a helmet and say helmets don't do a thing.

Same arguement with people who don't wear seatbelts while driving.

Try head butting tarmac with a helmet and say helmets don't do a thing.

Good point!

And then try without a helmet!

But make sure your helmet sticks out further if you have a big nose and last name is Speilberg!

mangatank – Member

"your scalp moves against the skull effectively lubricating the skull/ ground junction"

That really did make me throw up in my mouth!

Sorry – its a gory image but it would appear to be a real effect . By scalping yourself you might avoid a brain injury.

This is helmet with an artificial scalp and interesting direction for further work I believe. It might give a major improvement.

Similar to the Philips head protection system. Applicable for high speed motorbike accidents, not really for bikes.

LHS – that is the philips system. There are good indications that that or a similar approach is useful in cycle helmets -several papers including the TRL found significant rotational forces at cycle speeds. If a tech like this can eliminate this then why not.

Poc has a different system for the same purpose

Its a tech in its infancy. Worth looking at.

They already have a bicycle helmet with this technology in. I just don't think it offers any benefits for type and severity of accidents that occur on bikes. I know you disagree.

ooOOoo – Member

Try head butting tarmac with a helmet and say helmets don't do a thing.

Good point!

I was thinking more along the lines of stapling a patch of 60 grit sand-paper to the wall and then asking people if they want to wear a helmet or not, before they rub their head against the sand-paper…….. 😉

LHS. Reading your posts, I'm now wondering. Could you, with your expertise, outline what you think would move helmet design forward ?, in the name of better crash protection. I'm not implying that current designs don't work. Its just that I reckon there may be scope for improvement, and as you're current working in the field…

Like a list or something of features, technology that you're aware of, which you believe would be useful. And for now, perhaps ignore Manuf budget.

I'm not looking to pick fault, I'm genuinely interested in your comments as you are the one working on Aero helmets.
🙂

Solo

Sorry – its a gory image but it would appear to be a real effect . By scalping yourself you might avoid a brain injury.

This is helmet with an artificial scalp and interesting direction for further work I believe. It might give a major improvement

Hmmmm, not sure if i am understanding this correctly, BUT if your suggesting what i think you are, could you not just have, in effect, a matirial skull cap (shower cap type thing with elastic) over the top of the helmet, it is then changeable, and would act like a fake scalp, maybe elastic round the rim and velcro aswell.

i have probably missed something here, and will sound a right **** but what the hell!!

jon

nuts and volks – thats the concept. Needs a lubricating layer – or some other low friction surface yet to be teted – here is the mips system which is another way of reducing rotation

outline what you think would move helmet design forward ?

Thats a pretty vast question but i will try to keep it concise and within context.

From my point of view, the use of variable density EPS foam is something that should be used to control the rate of deceleration during an impact. Imagine if you will a liner made up of 3 layers, high, medium, low density EPS. This controls the rate of deceleration much better and also goes a long way to reduce the acceleration peaks when the EPS bottoms out.

I would like to see companies maintain multiple sizes of helmets linked to specific anthro ranges for men, women and children to ensure an optimal fit no matter what your head shape and size.

As an advancement of design, dual shell helmets are excellent in providing impact protection. You are able to build in design features within the layers whether its an air gap to allow initial flex and compression of the outer shell, or by building in flexible collapsible foam and rubber pillars which have a similar effect but can also help with any rotational effects. The downside is that dual-shell helmets don't lend themselves to a low profile, cool design.

As for the Philips system and similar designs, it is a great leap forward in Motorcycle helmet design but I don't think its applicable to the cycling community. It would help for example in the case of the road cyclist coming off on tarmac at 40mph, but for lower speed, lower energy impacts in cycling, I think it is a technology too far.

LHS.

Yeah, I knew that was a bit of a "catch-all" Q, but thanks for the comments. Just goes to show that those of us who think things still have some way to go, aren't asking too much, imo.

As soon as you mentioned varying density EPS structure, I had a dual or tri-layer structure in mind and I can see why this would yield an attractive crash performance.
Thanks.
😀

NutsnVolks.
I think I see what you're saying, but I suspect that an outer cap on a helmet would be a major snag hazard. Still, I like your thinking though.

Cheers.

Also, those designing the image of a new helmet. A real challenge would be to make a design along the lines LHS outlines above, into something that is acceptably asthetic.
I've worked in the Auto industry where the designers in their studio are sometimes tasked to "make-good" an Engineering solution that achieves its performance goals, but intially leaves a little to be desired by the beholder.
For me, this is how the best designers really rise to the top, incorporating performance into an asthetically pleasing form.

Ta
😉

Solo

I would also add a Helmet Mounted Display which would allow you to view and toggle between important information like heart rate, tyre pressure, Camelbak water level, number of jelly babies left.

With a suitable head tracking system you could link your handlebar mounted lights up so that wherever you looked they would follow!

😆 Excellent !.

Esp the Jelly baby count, absolutely vital, imo.

if spending £250 on a helmet got me "a jelly baby counter" i would definatly buy it, sod the safty factors. 😆

………How about HUD for………gps route !.

***runs away***

S

LHS – I don't know why you say

As for the Philips system and similar designs, it is a great leap forward in Motorcycle helmet design but I don't think its applicable to the cycling community. It would help for example in the case of the road cyclist coming off on tarmac at 40mph, but for lower speed, lower energy impacts in cycling, I think it is a technology too far.

There is a lot of evidence that this occurs at normal cycling speeds 15 – 20 mph with some rather frightening levels of injury ( although how applicable it is to offroad is unclear)

LHS – I don't know why you say

Experience.

The concept of the slip plane is simple on helmets, the need is a different thing completely. The whole point surrounds the need for the helmet to slide upon contact with the tarmac. Modern helmets with smooth shiny outer surfaces provide this function.

The simulations that are shown on the website assume that the helmet digs in and grabs upon impact. This simply isn’t the case. It also assumes that the user pile drives there head into the tarmac with no impact of the body first. In fact a very rare occurance. More prevailant for motorbikes if they are hit by a car at high speed and have no time to react.

The slip plane design also only provides about 10-15mm of travel which in high energy impacts is eaten through almost instantaneously and in fact can rotate the head and neck round to a more obtuse angle before the slip plane “bottoms out” just shifting the problem to another area. The control of the rate of deceleration in such a design is very hard to get right.

The additional height and complexity means for larger, higher profile helmets or less EPS and essentially higher moments as your head is further away from the point of contact.

The slip plane doesn’t work in all directions so it is only effective in certain events. I would be highly surprised if they could produce something so low profile which will work after being exposed to all the elements too – water, sand, dust, sweat. You would only have to get a small amount of dirt in there to change the characteristics of the slip plane.

The design doesn’t easily allow any cooling and adds weight.

Don’t get me wrong, I think its great what the guys are doing, I really do, any advancement in areas like this are always good. I just think in this particular instance they have created a problem in bike helmets that doesn’t exist. (And almost certainly ski and snowboard helmets)

Fair enough.

I have been going around the journals looking at stuff on it and find experimental results not simulations that show in at OTB at normal cycling speeds it is significant. I'll find you the references if you want ( easy enough search "cycle helmets rotation" in science direct using my athens password). Thats using modern helmets with shiny outers.

The biomechanics of injury are being questioned now – much of the type on injury that used to be ascribed to coup contra coup or linear accelerations some researchers now believe is rotation caused – so the scale of the problem may have been grossly underestimated to date. Many of the people who get concussion after head impacts while wearing helmets may have had this effect.

I take your point about the solutions not having enough of an advantage as yet. Its one of the conundrums with helmet design that improving it in one area might well make it worse in another – and weight is a real enemy as is size.

Cycle helmets aare always going to be a compromise

Its been asked who would pay £250 for a helmet.

Plenty of cyclists pay that much. Perhaps it is mostly fashion amongst DHers but there are plenty with Troy Lee D2s so some cyclists will pay larger amounts for helmets under some circumstances*. In fact I would venture that the issue for XC helmets is that there is a large discrepancy between what the suppliers can provide at the necessary price point and what is technically possible, if more XC riders were prepared to pay £250 for a helmet we might see some innovation and technical improvements. Sadly, at the moment all you seem to get for increased cost are weight and venting improvements and fashion.

*I also know that lighter MX helmets are popular amongst the knowledgable but this is more due to lower cost than any real or imagined extra protection.

This is one of the extremely few forum threads to change the way I look at cycling. Not through the arguments of either side, but from my own research because of the thread.

It's been eye-opening. Thanks guys…

..Still just bought a Catlike Whisper Plus though. If I'm going to have my brain stem rotated in two, I want to do it in style! 😉

Yeah, since we've all stopped arguing and started discussing the issues and solutions, its been a good thread, imo

My thanks to LHS and TJ, cos at the end of the day, like the rest of us, they only want helmets to save us.

I have appreciated it.
😉

Solo