Wouldn't change-of-state in the water reduce its cooling effect.

Engine block water is pressurized to increase boiling point, in order to allow the water to carry more heat away from the hot-bits.

Allowing steam to occur in the system ?, wouldn't that reduce system pressure ?.

Also, engine coolant isn't just water, boiling it would cause issues.

Generally, I've yet to be convinced on that one.

I wouldn't have an issue with a 7 seater carrying one person if the vehicle ran on a fuel which had much less enviro impact, or better, none at all, and was infinately reproduceable, cleanly.

Otherwise, Bus for the family, Aygos for all license holders of the house ?

Taxation ?, whos that going to hurt the most ?, those who can least afford it.

Anyone who suggests the £25 gallon, doesn't own or have to re-fuel a car, and so by that fact, has to have that comment ignored.

So, clubber, steam turbine in a car. Wheres the water coming from ?
Its quite heavy stuff too, IIRC.

Errr, yeah, heat is required for steam….What else though…

Edit:
That X6 hacks me off largely. What it says is
"Ha, I'm looking as if I'm rich, and whether I am or not, I'm going to make no attempt to contribute to a cleaner enviro.
Instead I'm going to let you do that while I tank around, in my tank"

Yeah, I do not like those cars, and I'm not sure I'd like the owner either.

As an alternative to hybrid electric, BMW are looking at adding a a medium pressure heat recovery system from the coolant system and exhaust to power a steam turbine directly attached to the crank shaft. Adds a further 10/15% to the overall thermal efficieny of the engine. Planned to be added to road cars in the next 5 years (IIRC) if development contiunes on track…..

I'd love to see that work in -30 degrees, +40 degrees.

Where does the steam come from ?.

and of course a 500 kg car could be made safe. How heavy is a smart? Whats its Ncap rating? ( well maybe 500 kg is a bit light but you get my point)

No, lets not generalise like that. How many people have a use for a Smart car ?. There are more Mondeos on the road than Smart two seaters.
This inidicates that there is a size-of-vehicle demand.

It would have to lose all the gadgets so beloved of modern motorists tho
Agreed. But you sell someone today, a car with no aircon, manual windows, etc…..
Again, customer driven, don't bash the manufs.

Unless you reduce the amount of materials in a car any "greening" remains greenwash
Agreed ^^^

Biofuels from crops can never work – there simply is not enough arable land to make enough fuel
Very limited thinking here. Ocean testing using ocean based plants is already taking place… ;-)

Lightweight technologies exist, the problem is cost.
Exactly. Carbon-monocoqe mondeo anyone ?.
***just dont mention the resin/recycle-ability of CF***blah, blah***

Car manufacturers are proft-driven
Yes, as well as car prices are market driven.
£60,000, CF Aygo, anyone, anyone ?

again not in the manufacturers interests
Wrong again. Manufs bring new cars as a practical function of tool wear and customer/market demand for new cars.
Production tools wear-out. When they do, you either re-produce those tools and keep knocking out the same car for more and more money, like whos going to pay more for the same car/10 year old design(workforce wage demands/inflation). Or, faced with the prospect of ordering new tooling, you produce a new car, which can incorporate new design features for…safety and economy.
Knocking-out the same car for 300 years isn't a flyer, imo.

NO car manufacturer will do this tho as it has no profit in it.
Again, not correct, please, please understand Manufs have to respond to what WE buy and what Govs suggest they would like to have offered for sale. Blamming the Manufs alone, isn't really addressing the issue.

Lots of carrots and sticks are required, but Joe Public has a hand in this too. Shouldn't the new-car buying public get-real too ?.
BMW wouldn't shift a single X5, if people decided that they we're going to descriminate against stupidly sized soft-roaders.
And while I'm here. WTF is that BMW monster that looks part X5 and part coupe.
Imo, that car really takes the P155 out of trying to address car emssions/fossil fuel consuption.

Cat.

yhm

if road tax was per kg and escalated rapidly after 500 kg how long till the 500 kg car?

TJ, I'm surprized you wrote that. Crash preformance of the 500Kg car is ??…Wouldn't the Mondeo already be 500Kg, if it were possible ?, the Manuf would love that.
Modern car weight is not a simple issue. On the one hand, Maunfs want to produce a lighter car, on the other hand, the customer demands more in their cars, not withstanding the crash preformance demanded by authorities in any particular market.

Molgrips, you work in Auto ?.

As I've written before, battery powered cars as we know them today, are not the final solution. Far from it.

GM microbes recycling waste into alcohol based fuels is one credible goal.
As an interim phase, plant material in the form of arable crops, is used to produce fuel, although ultimately, I'd like to see a move away from that. Which is starting to happen, espically at the testing stages.
(Don't even think about whinging about starving masses, I'm not even going to entertain remarks about that cr4p)
Unfortunately, any benefit from producing loads of nigh-on carbon neutral fuel, is p155ed away by producing it using conventionally powered agricultural machinery, then transporting it by conventionally powered vehicles/shipping.

Even then, I wouldn't suggest that carbon neutral should be where it stops.

For the next 50 years, heading towards producing a liquid type fuel to run engines in a similar format to todays motors, is the best we could reasonably hope for, imo, when stepping back and trying to appreciate/consider the Big Picture.

The Honda clarity ws along the right lines, but for the fact it was hydrogen powered.
Again, I have explained why the Hydrogen powered car isn't a real-world solution.

So, is that it, is that all the T-Shirt recommendations there are ?.

;-)

I 2nd OnzaDog.

How long till that t-shirt is on sale in the Shop…

;-)

Ah, STWF.

Can turn even a What T-Shirt thread into a flame-off. ^^^

:roll:

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

Get a mohawk hair cut, wear a combat jacket, walk up to them and ask..

You lookin at me ?.

Though if they go up on a Sunday morning it saves you a couple of jobs…

Stranger things have happened….by accident, allegedly.

Be careful with your automatic chicken door.

Check it will still open if a fire breaks-out in the coup.

I reckon they should run those saftey ads on TV again, warning chickens never to smoke in bed.

S
EDIT: Oh, and if you do fit one, send your chickens off to a training course for "In the event that the posh door to your bedroom doesn't work.."

Upside-down style forks ?

………How about HUD for………gps route !.

***runs away***

S

:lol: Excellent !.

Esp the Jelly baby count, absolutely vital, imo.

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.
:-D

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

Now Radio 4 at bedtime… now yer talking

Now you see, I'm a Radio 4, Today program, listener, Oh !, and Farming today, thats good too.

But my favourite, recent discovery is Desmond Carrington. That show absolutely ROCKS !. Not literally, but I really like that show.
Just so totally different and interesting. Shame on BBC2 for moving him to Friday nights, or beer night, as it is in my part of the world.
Thank goodness for iplayer.

Solo

What;s happened to Steve Wright?

I've been wondering the very same thing. Hes a twit, and quite arrogant with it too, but I understand his sense of humour, and listening to him on the drive home, was a lesser evil than other avaiable stations.

Anyway, who ever replaces wrighty, I want ASK ELVIS back !.

Solo

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

Nobody is really sure where/when zero came about. But yes, its very, very important.

What have we done for the Indians ?…

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

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.

So for protection for bikes it will be the perceived types of accidents that are prevailant and also your aesthetics and weight issues will come into it. You can't add that amount of structure to a helmet without it looking ugly and adding weight

And so there in lies the current circumstances that have lead to current designs ?.

As cycle helmets have moved towards the Look of todays current design with perhaps a disproportionate emphasis on cool/ing.
I would expect that most manufs might consider it too much to try to develop in an alternative direction.

But this could also be the challenge.

To actually add the material, where it would seem to be needed, but also, imo, to look at how the EPS structure contacts the head, and how the helemt is secured to the head.

As I posted earlier, due to all the venting along the top of my helmet, the EPS has only relatively slim, contact patches, touching my head.
So therefore to achieve the desired pulse, I'd expect that the available contact area would influence the density, etc of the foam selected.

If the contact areas could be increased, could one use a lower denisty of foam, thus perhaps not increasing weight quite so much ?.
All subject to testing, obviously.

And I still wonder whether a thin layer of another type of material, a liner, would also assist in reducing the forces experienced during impact.
:-)

Ta

Solo

im happy to take my chances and continue wearing one in the hope it makes things a little less worse if/when i have an off

Yeap, I'd agree with that.
:-)

I have to admit, cooling is a secondary concern for me, when considering how future helmet design might improve for its primary function.

What I don't like about my helmet is that it only seems to cover the top of my head, reaching only a short way down the back.

I guess I'd prefer more coverage, and was hoping LHS might throw some light on whether that would be a good direction to develop towards.

I'm also distracted by the breakage of helmets, but I'm guessing that once the impact reaches forces that exceed the HIC, then failure is possibly the only option.

Other sports seem to employ helmets that offer more coverage, but as others have pointed out, most MTB'ers, me included, like not to suffer a massively hot head.

I just can't help thinking that perhaps current helmet design has got stuck into a rut, based on performance, cost, manufacturability, sales, etc.

As I posted way back on like the 2nd page, whos going to stump-up £250 for a helmet ?, esp now that super markets have sold basic, conventional looking items for less than £10 ?.

Initially I resisted trying to design a cycle helmet by posting on a thead, for its pratical limitations, but then I realised that if someone such as LHS was going to contribute, then perhaps we could at least discuss general features that we'd either like to see come-out in new designs, or stuff we think we'd like to see the end to.

Another feature is the strapping. Seems to me that the strapping wraps around my head, but still allows the structure of the helmet to "wobble" around on my head, ie, theres still a fair bit of "play" once the strap is done-up. I know we can't all be laser-scanned for the fitment of our new helmet, but perhaps theres another strapping strategy thats being over-looked on the basis of what is curernt and cost effective.

S

LHS is long gone. He's too busy mucking around with stuff like this

Yeah, could be. Shame though as LHS has current experience, etc.

Oh well, worth a try.

;-)

S

It's been tried. You can't have big enough hole at the front.

Perhaps the entire leading edge could be open, feeding a duct network inside the foam, but the ducts pass through the foam/EPS and only have a max opening of 4mm at the bottom of the duct, onto the head.

LHS. Still with us ?.
:-)

S

Also, just thinking about issues with the Peak on helmets, possibly causing problems.

Break-away has been mentioned I think, IIRC.

How about soft rubber ?, weight permitting…

Then the peak coud just flex away, against the helmet/forehead.

S

My helmet has contact points in the upper region, on the top of my head.
I'm thinking that they become the point of load during an impact.

I'm also thinking about the smoother, fuller contact area of other types of crash helmets that cover more of the head area.

An issue though would be cooling so as the helmet wasn't so hot as to be unwearable.

Perhaps leading edge ducts send air along the head and vent at the back, possibly incorporating some of the frangibles, if testing could provide a frangible pattern that lent itself to this dual purpose.

Just throwing a few ideas about.

S

Could the frangibles serve a dual purpose of ducting air over the wearers head ?.

Molgrips.

How would such a cooling device be powered ?, where would the components go in the event of impact ?, drive in towards the wearers head ??…

That helmet looks interesting, but do all those vents result in point contact on the wearers head ?.

Also, does the rear of the helemt need to wrap around the lower part of the back of the head ?.

S

LHS.

Thanks. Yes, I see that head shape and size would have to be dealt with to provide a mass production solution.

The cost, as you point out, is a question I kinda pointed at in earlier posts. Any scope for a similar but less costly mat'l to CFRP ?.

Multiple density foam, now we're talking. Again, I've no idea of whether the cost would be prohibitive for application to cycle helmets.

Ref the liner, are you referring to the main Foam structure or a thinner layer that actually contacts the wearers head ?.
Like:
Outer shell
Foam structure inside
thin liner of appropriately soft mat'l

Do you think it would be possible to achieve the desired pulse without the foam/EPS failing ?.

After all this, I would include, cooling. I reckon that heat build-up is one of the things thats going to get people taking their helmets off.
At the moment, my helmet has many vents in it, which give rise to the EPS only have point contact with my head in those areas.
Could we vent a helmet in another manner to increase the amount of foam in contact with the head ?.
Just thinking out-loud, Nasa ducting on the leading edge, sort of thing ?.

Cheers.

Solo

LoL @ Clubber ;-)
Good one.

So, this being my first "helmet" thread, but being somewhat familiar with STW-F.

I am disappointed that this has turned into a true flame-war about injuries, but not surprized.

I was really more interested in where helmet design goes from here, and why.

LHS. Clearly you have experience and knowledge of this matter. Surely it would have been better for you to contribute on how things can be improved, as you admit there is room/scope to furthering helmet design.
So, how can the design move-forward ?, iyo.
(genuine Q)

TT. Imo, its gonna be difficult to design a cycle helmet in detail, on a forum thread, so much so that I wouldn't consider it practical. However, with LHS's and others contribution, would it be too difficult to discuss general features ?.

When TJ posted a few comments on what he'd like to see on helmets, I had hoped that would kick-off such a discussion, but alas it hasn't gone that way.

I'm not that interested in arguing other people's research, yadda, yadda.
Rather, how could the current day design be improved to perhaps, increase crash performance.

LHS. What say you to an outer cover that doesn't crack on initial impact, but rather deforms thus keeping the EPS from cracking ?.
I would think that a different density EPS would be required so that energy could be dealt with before the EPS failed ?.
:-)

Solo

LeeW.

Considering you're staying in a hotel, I think you've done quite well.

If your SO is already eating that kind of stuff, then you have an inside track on meal ideas for, as you put it, if and when you get home.

:-D

What does "XO" mean ?, please.

molgrips – Member
Lol. Say that again and I WILL KILL YOU!

Molgrips, I nearly PMSL at your post. You know, although you insulted me quite badly today, I've still got to like you for your OT responses to some posts, on some threads.

Like when you offered to insert your knee into SFB's skull. Its classic and very funny, in a slap-stick kind of a way.

:-D

S.
EDIT: scruff – Member

I WILL KILL YOU!

Dude, Im still 15stone

Oh, please stop, I can't breath.
***fantastic***

Anyone tried eggs and marmite for brekkie ?

Is the Sun hot ?. H3ll yes, its Fab.
:-)

S

Would you wear a full face helmet when out on a road ride?

Should have gone to spec-savers

Just what are the real, effective differences between MTB and Road helmets, in relation to them performing their ultimate function, in their current form ?.

:roll:

S