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Sledding athletes are taking their lives

nytimes.com

151–160 of 241 posts

Re: Sledding athletes are taking their lives

#151
post #12

Earlier quoted context omitted.

The issue with helmet design is likely the same one football players face: that the place the impact absorbing material needs to go is between skull and brain. There’s no wearable helmet that’s going to change the result of skull being decelerated or accelerated as the brain keeps going. A strap or some padding that absorbs fleeting contact with the ice maybe has a chance to make a difference, but there are so few pe…

I'm no expert on helmet design, but surely you can absorb that force elsewhere, as long as the acceleration on the skull is damped? Degenerate case: a car's airbag does not go between my brain and my skull, yet it does prevent my brain from slamming into my skull.

> a car's airbag does not go between my brain and my skull, yet it does prevent my brain from slamming into my skull

No it doesn’t. The airbag stops your head. It doesn’t stop your brain.

Re: Sledding athletes are taking their lives

#152
post #145
post #65

Earlier quoted context omitted.

It would not be the first Olympic sport redesigned for safety concerns. The first one that I am aware of is Javelin. See https://en.wikipedia.org/wiki/Javelin_throw#Javelin_redesign... for more.

That case though was about safety of the audience, says the article.

True, but nevertheless it shows that it can be done.

Formula 1 and motor racing in general is a prime example for that as well. Formula 1 has a strict set of rules that makes sure the speed and cornering speeds aren't going through the roof because of deadly accidents in the past.

The same could be done for sledding. Reduce speed by limiting what is technically allowed and improve protection of the athletes. From reading the article i could imagine that a headrest with a dampening foam is added to the sledge and prevent the helmet from touching the ice. Or add role bars to the sledge that protects the athletes from injuries during a crash. Or a emergency brake that stops the sledge from sliding all the way to the end after a crash. There are many more things that i can imagine. If it all makes sense has to be evaluated. But first the political will to change something has to be there. And i think that's the difference between formula 1 and sledding. In one sport there was instant death of the athletes and in the other the athletes deteriorated over time.

Re: Sledding athletes are taking their lives

#153

Earlier quoted context omitted.

That won’t handle the number of degrees of freedom a bobsled uses.

True. How about suspending a little metal bullet in a gel, chosen such that the bullet will break through the gel if the G-force is more than a certain threshold. This will give a good indication if the forces are within an acceptable range.

Reminds me of shockwatch for packages.

Re: Sledding athletes are taking their lives

#154

Earlier quoted context omitted.

Just thinking this through, wouldn't three weights on springs get you all the data? Or some sort of membrane containing a liquid than ruptures when a particular amount of force is felt in any direction?

The problem with three axes is that the registration of the largest deviation by the pen happens for the axes independently.

Yet its still valid data in that its trivial to calculate the theoretical maximum peak accel based on the possibly independent peak accels of the individual axes.

If in theory the max peak acceleration could never exceed 2 G then there's no point in continuing the study. If the theoretical max peak accel could be 57 G then there's a point in continuing the study.

The whole problem is irrelevant anyway. The problem isn't one individual sled journey, the problem is thousands of competitors taking thousands of rides over many years, so "tens of millions". They are competitive with each other having small std deviations in performance so each sled ride is roughly the same. Tiny reliable cameras have been a thing for a century as have mechanical timers. Simply bolt a half pound telemetry package to every sled that snaps a single random point of data via camera or some weird linkage to clutches and springs. Then run a data analysis and make statistical predictions. You wouldn't even need a 1960s mainframe to run the statistical analysis. This would have been something near BAU for mid-century aeronautical engineers, for example. I'm sure something similar was implemented during the test program for the F-86 or maybe P-51.

Re: Sledding athletes are taking their lives

#155

Earlier quoted context omitted.

I think the Olympics is just generally physically bad for the athletes. Runners, weightlifters, wrestlers, boxers, rowers, etc all these folks end up working so close o the edge of sustainable human tolerance and capacity that’s it’s unlikely they are not constantly going over it.

I don't understand this comment; what is physically bad about running? I'll accept that you may have a higher rate of injuries but surely we can agree that pulling a muscle and giving yourself Parkinson's are not remotely in the same ballpark of injuries.

Knee implants, significant negative hormonal changes for men over 50 miles/wk. Repetitive stress injuries are no joke.

OP is probably not aware that the Olympics does not have ultra-marathon type events which are generally very unhealthy for participants, only a 10K and a marathon (and shorter sprints of course)

Re: Sledding athletes are taking their lives

#156
post #15

Earlier quoted context omitted.

Except measuring G-forces acting on a helmet doesn't directly relate to the forces acting on the head within it.

It doesn't matter. You don't have to measure something perfectly and exactly to decide if it's an avenue of research worth exploring. If turns are designed to limit G-forces to 5G, and you put sensors on your helmet and they're reading 55G when your head hits the ice, that's probably an indication that further research is required.

You could have >55G when you stay in your room and bump your head against the wall

Re: Sledding athletes are taking their lives

#157
post #127
post #117

Earlier quoted context omitted.

Actually the whole point of having a helmet is to not have your head track its movements - if the acceleration transferred to your head would be the same as that suffered by the helmet, you might as well not wear one at all. Same as with old cars with a stiff body, where in an accident the passengers were subjected to almost the same deceleration as the front bumper. Using the front portion of the car as a crumple zo…

Newer helmets are designed to be loosely coupled in twisting motions as well as direct impacts too, reducing the ability for the helmet to transfer angular momentum (at least that's the stated goal)

Yeah, for anyone interested there is a technology called MIPS in newer helmets that is intended to handle this better. There are some explanations and diagrams on the site https://mipsprotection.com/

Re: Sledding athletes are taking their lives

#158

This seems totally unacceptable. We should stop having this sport in the Olympics (implicitly supporting this madness) -- of course athletes are free to do as they chose, but we cannot encourage such pointless self-destruction and misery. An alternative to save the sport is completely redesign it to limit maximum accelerations. Usually injuries follow power laws so I doubt even that much reduction would be necessary…

> Usually injuries follow power laws That's a pretty outstanding claim, do you have any evidence for this?

I'd bet a case of beer that OP did operations analysis in his MBA course... The term to google for is "Duane Power Law" or similar. Duane was the first statistical process improvement researcher in the 60s to graph MTBF stats and discover breakdowns follow a power law. There's a lot to see if you google for that.

Of course humans aren't machines... or are we? Pretty weird how wildly different factory floor industrial machinery all follow the same power law. I would be surprised if humans did NOT follow some kind of power law of injuries based on total cumulative energy dissipation in tissue over time or something like that. Humans can heal better than a milling machine or EDM cutter. On the other hand humans take terrible repetitive strain damage, so maybe Duane is right after all.

Re: Sledding athletes are taking their lives

#159

Earlier quoted context omitted.

And to think that the sport that actually did Schumacher in was skiing - something millions of people do casually every weekend. My point is that while there has to be a thrust on safety, even the mundane can be unsafe enough; you can't overstress safety

where i live (especially in my local region) tourism is huge. especially in winter. and IMHO skiing is one of the most dangerous winter activities you can do. i honestly always bring this up because i think skiing is wrongfully seen as a "casual activity". having worked in a hospital for some time, you wouldn't believe how many accidents we receive in winter just because of skiing accidents. it's by far the worst tim…

The thing about skiing (and snowboarding) is that improving measurable performance almost always requires taking more risks - harder trails or higher speed. Contrast with running, for example, where increasing speed involves no risk at all. Most people want to improve at what they do, so the ski resorts are filled with people at the edge of their ability, all in proximity to one another. That plus the sheer speed practically guarantees a high injury rate.

Personally, while I do challenge myself in those ways some of the time, I'm just as happy seeing how many turns I can make on a run I've already mastered, or trying to make each turn absolutely perfect. Slight increase in risk, but much less than the human cannonballs I see around me.

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