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How well do cars do in crash tests they're not optimized for?

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Re: How well do cars do in crash tests they're not optimized for?

#251

Post by mdorazio »

laegooose wrote: post #5

The whole car safety topic is very confusing. Car accidents is top1-top2 death reason in US for people in 20-40 age group [1]. Probably less in Europe but still one of the leading ones. I was thinking about how I can make myself safer. Which car brand/model is better? Which seat is better for passenger? How much riskier it is to drive during the night? In the rain? How dangerous is it to overtake on road with 1 lane…

NHTSA has a fairly good repository of research, although it doesn't cover everything you're looking for [1]. It's been a while since I reviewed the statistics, but I recall that highways are significantly safer than high-speed undivided "surface streets". Intersections, and specifically left turns at them are also more dangerous than other road areas. There is also some scattered research like [2] on related topics, for example showing that overtaking accounts for relatively few total accidents, but has an outsized percentage of fatalities (as you would expect due to the collision dynamics).

[1] https://www.nhtsa.gov/research

[2] https://www.sciencedirect.com/science/article/pii/S235214651...

Re: How well do cars do in crash tests they're not optimized for?

#252

Post by balfirevic »

apcragg wrote: post #120
wscott wrote: post #30

The article reminds me of a story from a friend that was an engineer at a major water heater company. Modern electric water heaters are already fairly efficient, but every model gets tested by the government to be given an efficiency rating. The test consists of replacing the anode with a rod that has a series of temperature probes to measure the water at different levels in the water heater. Since water would form l…

Is that not outright fraud? Just because you can hack something doesn't make it right or legal.

How far out of optimal (for testing) position would you require their water temperature layers to be?

Re: How well do cars do in crash tests they're not optimized for?

#253

Post by coding123 »

kube-system wrote: post #90
cybrjoe wrote: post #82

Earlier quoted context omitted.

Serious question, how is this different from what VW did? There was a lot of talk about complicit engineers vs. shady management in that discussion. Did this ever make it to production?

The big difference with VW is that they put in a mechanism that detects the test and completely changed the behavior of the car for the test.

That sounds exactly like the third sentence of the article.

> Sun managed to increase its score on 179.art (a sub-benchmark of specfp) by 12x with a compiler tweak that essentially re-wrote the benchmark kernel.

Re: How well do cars do in crash tests they're not optimized for?

#254

Post by Marsymars »

mohaine wrote: post #46
bcrosby95 wrote: post #25

Earlier quoted context omitted.

Driving is already incredibly safe. Yes, it's the leading cause of death in those age categories, but there are 3-4 trillion miles driven each year in the USA. That comes out to 1 death every 100 million miles.

This. If driving was the only cause of death, and we did nothing but drive from birth we would expect to live to ~250 years old on average.

That number makes driving feel less safe to me.

Re: How well do cars do in crash tests they're not optimized for?

#255

Post by katbyte »

BurningFrog wrote: post #233
throwaway0a5e wrote: post #185

Earlier quoted context omitted.

>Transgender icon J Edgar Hoover Citation please. This is the first time I've ever heard him called that. There was some speculation he was gay but nothing conclusive AFAIK. In any case he's one of the last people anyone should pick as a positive representation of their group.

The cross dressing claims are pervasive but not very substantiated. So we can all believe what we want. I was just trying to be witty when telling a story. Not make any grand statement about anything.

regardless crossdressing != transgender

Re: How well do cars do in crash tests they're not optimized for?

#256

Post by Marsymars »

AgloeDreams wrote: post #226
laegooose wrote: post #5

The whole car safety topic is very confusing. Car accidents is top1-top2 death reason in US for people in 20-40 age group [1]. Probably less in Europe but still one of the leading ones. I was thinking about how I can make myself safer. Which car brand/model is better? Which seat is better for passenger? How much riskier it is to drive during the night? In the rain? How dangerous is it to overtake on road with 1 lane…

You are spot on. What's really interesting is when companies publish death rate numbers. In everything I've seen, most low-cost car models suffer on safety, generally due to lower cost construction, materials, or cheaper safety/avoidance systems. Volvo obviously has historically been the best at reducing mortality, Tesla is seeming to be beating them but I don't know how many of the numbers actually match reality, th…

> Oh and SUVs are markedly LESS safe. They are more prone to rollover, less likely to avoid an accident, stop slower, and generally have less safe body structure.

But they're also heavier, and there exist cheap, heavy SUVs, while cheap cars are generally lighter.

Re: How well do cars do in crash tests they're not optimized for?

#257

Post by jbay808 »

globular-toast wrote: post #161
jbay808 wrote: post #77

Earlier quoted context omitted.

It's the "let's defect in a prisoner's dilemma" strategy that works great until others use it too.

It is not the prisoner's dilemma at all. If everyone gets big cars then everyone is equally as safe. They don't all die. For crying out loud, people, I know it's stupid, I know it's wrong, but it's the truth. It's an uncomfortable truth that your downvoting will not change.

It is a prisoner's dilemma.

When you all have big cars, you're back in an equilibrium where everyone seems as safe in head-on collisions as the equilibrium where everyone drove small cars. But each car now has way more kinetic energy and momentum, and needs bigger crumple zones to absorb it (oops! You won't find room to expand those in side collisions!), is more prone to rollover, has less visibility of pedestrians, bicycles, and children playing in your driveway, worse gas mileage, more pollution, less parking space, etc.

And then someone decides to get an edge over the crowd by driving a monster truck and you're back to scrambling into a new, even worse equilibrium.

Re: How well do cars do in crash tests they're not optimized for?

#258

Post by jmchuster »

YetAnotherMatt wrote: post #147
hangonhn wrote: post #98

Earlier quoted context omitted.

Can you explain more about the walking part? Is it because pedestrians get hit by cars a lot? Otherwise it seems walking should be incredibly safe.

Like some of the other comments already mentioned, its indeed on a per distance basis. Also traffic accidents are far more deathly if you're walking basically naked from a safety perspective vs protected by a well designed mass of metal. When a car and a human collide, it's not the driver that's likely to die. I got my stats from https://en.wikipedia.org/wiki/Micromort which shows walking approx 12 times as dangerous…

FYI, here's where they get the 12x more dangerous data from:

https://web.archive.org/web/20091122180337/http://www.statis...

Re: How well do cars do in crash tests they're not optimized for?

#259

Post by arkades »

WWLink wrote: post #137
komali2 wrote: post #61

Earlier quoted context omitted.

Riding motorcycles means I'm often playing the percentages game. When we turn we're sacrificing our finite amount of traction for either more speed or a more aggressive turn. If I lean off the bike, I get some traction back. So how much am I willing to sacrifice in the name of fun, while still leaving wiggle room for suddenly encountering a tar snake or something in the middle of my turn? Little things. Motorcyclists…

"if you have to think about it for a second, just don't do it. Thinking about that narrow pass on the freeway? Let it go, you can pass in a couple seconds after the gap widens. Thinking about gunning through the yellow? Relax. Just stop. Etc." That totally applies to driving a car as well!

It's not thinking that gets me into accidents - it's not thinking that gets me into accidents.

That also applies to driving.

edit: Unintentional. I meant, it's not those situations where I think for a second and make a bad call - it's those situations where I act without thinking at all.

Re: How well do cars do in crash tests they're not optimized for?

#260

Post by AgloeDreams »

Marsymars wrote: post #256
AgloeDreams wrote: post #226

Earlier quoted context omitted.

You are spot on. What's really interesting is when companies publish death rate numbers. In everything I've seen, most low-cost car models suffer on safety, generally due to lower cost construction, materials, or cheaper safety/avoidance systems. Volvo obviously has historically been the best at reducing mortality, Tesla is seeming to be beating them but I don't know how many of the numbers actually match reality, th…

> Oh and SUVs are markedly LESS safe. They are more prone to rollover, less likely to avoid an accident, stop slower, and generally have less safe body structure. But they're also heavier, and there exist cheap, heavy SUVs, while cheap cars are generally lighter.

Weight increases mortality in all accidents. Either by increasing the likelihood of the other driver being injured or by increasing the amount of force impacted on crumple-zones in single car accidents. All modern safety studies have shown this and only recently has any SUV gotten a pure 5 star award. SUVs are less safe than equally priced cars. Also most SUvs cost much more than cars with similar wheelbases.
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