Calling all engineers and crackpots

[jake7140]

Since Greg has handled the current generation of H&N devices (very handily I might add), my mind got to thinking of the "next gen" H&N device. What might such a thing look like, behave like, etc.? Some free decompression time over the holidays turns the mind loose.

Let me raise ip an idea, that while perhaps far-fetched and fraught with technical issues (isn't all the truly great/fun stuff?), could possibly be an interesting path.....

A balaclava-like garment, that
when a small electrical current is applied,
becomes rigid.

Some or similar technology already exists, in LCDs, sunroofs that vary based on electrical inputs, and probably other stuff that I am not even aware of. Perhaps the fabric's threads would be the reacting element, and then woven together. Perhaps a wetsuit-like garment filled with a reactive gel, the list could go on.

The garment could be triggered by the same type of device that triggers airbags, placed on the helmet or elsewhere.

And only one connection for those that are (ahem) concerned.

Thoughts, cannonballs, ideas.... labs, manufacturers....???? Let the mind wanderings begin!

[Jiveslug]

Thats actually a pretty interesting idea, Jake. The only potential problem that I can see with it is in regards to the same reason why we pull airbags from racecars: preventing accidental activation. In my somewhat limited track experience, Ive noticed that you can get jarred pretty easily from hitting curbing, maybe some light contact, rough racetrack, etc. If you can find away around that issue, it would be a good step.

[MMiskoe]

Perhaps I've missed something along the way, but I've often wondered why we need big, complicated, expensive things to keep our heads in the same vacinity to our shoulders when our shoulders are mearly tied to the back of the seat. Why not just have an additional strap(s) that tie the helmet to the same stuff the harnesses are tied to? Someone once told me that Navy pilots landing on carriers have a hook on the back of their helmet to keep their head in place while the plane catches the wire. This just seems so simple.

I've been wanting to ask this question for a while, I'm sure there's an answer. I also expect asking the question will sway peoples opinion of me more towards the second personality Jake has called to.

Matt

[jake7140]

Originally posted by MMiskoe@Dec 30 2005, 06:29 PM
...... This just seems so simple.

I've been wanting to ask this question for a while, I'm sure there's an answer. I also expect asking the question will sway peoples opinion of me more towards the second personality Jake has called to.

Matt

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Simplification is always a desired trait. Take the 2-stroke/rotary engine for example.... (duck). Sometimes it's as simple as "Doh, why didn't I think of that?", sometimes it takes a lot of technical innovation.

Innovators throughout the ages have been considered crackpots. I'd like to use it as my excuse, but let's not go too far.

[Greg Amy]

Originally posted by MMiskoe@Dec 30 2005, 12:29 PM
Why not just have an additional strap(s) that tie the helmet to the same stuff the harnesses are tied to?

[snapback]69591[/snapback]

The first-generation Wright Device did exactly that: used webbing that attached to the helmet which was then threaded through the buckles on the shoulder harnesses. The helmet was secured to these straps using the same GM-style seatbelt buckle as is currently used on the body harness.

http://www.over40racing.com/images/n66prlla.jpg

In fact, my transition from the first one to the body harness was without any changes to the helmet assembly. I can still swap back and forth at will.

I don't know this for a fact, but it was probably due to Pro's requirement for single-point release that Jay chose to pursue the body harness version. Details on the shoulder harness version are still available at:

http://www.over40racing.com/The%20Wr...vice%20Pro.pdf

[dickita15]

Originally posted by GregAmy@Dec 30 2005, 04:05 PM

I don't know this for a fact, but it was probably due to Pro's requirement for single-point release that Jay chose to pursue the body harness version. Details on the shoulder harness version are still available at:

http://www.over40racing.com/The%20Wr...vice%20Pro.pdf

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That first gen device was nixed long before the single point of release argument surfaced. What i had heard thru the grapevine in that with belt strech on the first setup the your body could move and your head was held rigid.

[gsbaker]

Originally posted by dickita15@Dec 30 2005, 04:14 PM
That first gen device was nixed long before the single point of release argument surfaced. What i had heard thru the grapevine in that with belt strech on the first setup the your body could move and your head was held rigid.

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Dick,

That's what we heard also. At the time, people probably erred on the side of caution with that decision, only because it was one of those things that could not be nailed down.

I'll bet, with all that is known today, that design concept could be tuned to work very well.

[ddewhurst]

***Innovators throughout the ages have been considered crackpots.***

I'll buy into that.

My question to ya all is, IIRC most sleds that have been shown have the shoulder harness at horizontal to the top of the dummy shoulders & not to the for example spec set forth by Simpson that the shoulder harness shopuld be anchored 4 inches below the top of the shoulder. Hmmmmm

[RacerBill]

***Innovators throughout the ages have been considered crackpots.***

I'll buy into that.

And I'll second that!

My question to ya all is, IIRC most sleds that have been shown have the shoulder harness at horizontal to the top of the dummy shoulders & not to the for example spec set forth by Simpson that the shoulder harness shopuld be anchored 4 inches below the top of the shoulder. Hmmmmm

I am not familiar with the Simpson installation spec, but it would seem to me that the angle was the important measurment. 4" may or may not work, depending on the distance from the shoulder to either the mounting point or the harness guide (ie the horizontal bar in the roll cage). The main hoop of my roll cage is right behind the seat, and the shoulder harnesses are mounted to tabs welded on the back of the horizontal bar. The top of the horizontal bar is at the same height as the top of my sholders. The distance from the bar to my shoulders is 6" to 8". If the bar was 4" lower, the shoulder harness would be angled down at much too great an angle.

BTW, my cage builder also lowered the bottom of the shoulder harness opening in my seat so the harness straps would be as close to horizontal (or perpendicular to my spine) as possible.

(Hope that's right, this is my first car!)

[ddewhurst]

Bill, I made the comment as stated in my first post per Simpson specs. After reading your post I looked at the SCCA GCR spec & they show & say 90* to the spine.

Anyone else have a spec from another manufacture ?

[gsbaker]

When expressed as an angle off of horizontal we've seen it presented as a range. From about up 10* to down 20*, but it varies between manufacturers.

Anything close to horizontal will work well for upright seating. Personally, I like the GCR approach.

Please do not do this:

[x-ring]

by "this" I assume you mean the 45* angle down from the seat back to the cage attachment?

[ddewhurst]

Ty, the first thing I view in the photo is that the the harness openings in the seat are to high for the driver shown.

[gsbaker]

Originally posted by x-ring@Jan 3 2006, 02:38 PM
by "this" I assume you mean the 45* angle down from the seat back to the cage attachment?

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Yes. Anytime the belts go up from the shoulder toward the seat back too much the belts are unnecessarily overloaded. As David noted, the solution here is to drop the hole in the seat.

We have a customer with a similar setup who crashed. The belt load was so great on the aluminum seat that the seat back bent forward.

Anytime the belts go down too much the spine can be unnecessarily overloaded.

[jwalter]

Originally posted by Jiveslug@Dec 30 2005, 01:27 PM
Thats actually a pretty interesting idea, Jake. The only potential problem that I can see with it is in regards to the same reason why we pull airbags from racecars: preventing accidental activation. In my somewhat limited track experience, Ive noticed that you can get jarred pretty easily from hitting curbing, maybe some light contact, rough racetrack, etc. If you can find away around that issue, it would be a good step.

[snapback]69590[/snapback]

Non-newtonian fluids, specifically, dilatants. You know, the famous cornstarch-water experiment we all do in school.

If you use a liquid that reacts more rigidly, but only under higher agitation. Put that in a gel "balaclava" under or attached to the helmet and over shoulders, and under the belts. Under significant loads it becomes semi-rigid, but under normal conditions it is a fluid allowing full range.

It works equally well under side load, when the head is turned, chin tucked, sticking out your tongue, etc.

I just thought, F1 guys would like it b/c it would help relieve some of the strain on thier necks under heavy accelerating or braking.

[x-ring]

Originally posted by ddewhurst@Jan 3 2006, 11:58 AM
Ty, the first thing I view in the photo is that the the harness openings in the seat are to high for the driver shown.

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Oh yeah, duh. At my height nothing is ever too high in a race car (usually it everything is too low...) so I didn't even think about the harness holes.