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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?

#111

Post by jhardy54 »

shoes_for_thee wrote: post #43
baxtr wrote: post #28

Earlier quoted context omitted.

I wonder what happens if you compare driving to other activities, by stretching them out to the 3-4 trillion miles - but in time and then compare death rates. E.g. taking swimming 2hrs per day (maybe equivalent to the 2-3 hrs spent in cars daily). Higher or lower death rates?

This might have some useful info for you... https://www.cyclehelmets.org/1026.html death rates per million hours of activity

Do you know what 'residential fire' means? I'm imagining a scenario where my residence is on fire, which would seem to be high-risk (but is somehow the lowest risk).

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

#112

Post by kube-system »

pbhjpbhj wrote: post #103
kube-system wrote: post #59

Earlier quoted context omitted.

The person is not suggesting it's a statistical flaw -- but that it's a self-selection bias. Hypothesis: The people who opt to spend more for a 4wd version are people who know they will use it because they operate the vehicle in inclement conditions, and/or they are uncomfortable with their ability to operate a 2wd vehicle in those conditions and/or they do not have the option to stay home when the weather is bad.

It can go the other way too, they don't buy it to drive in inclement conditions, but once they have it they increase their driving in inclement conditions because "4x4s can go in any conditions". 4x4 drivers might do offroading: so the figures could be much lower than if those people had 4x2 (2wd) vehicles.

I think recreational 4x4 is niche enough that it is probably not significantly represented in the data (and those accidents are mostly single-vehicle and probably less likely to be reported)

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

#113

Post by duxup »

cybrjoe wrote: post #82
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…

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?

VW's vehicles did not meet the standards required when used every day. They only met the standard during testing.

The water heaters don't sound like they'd fail any given test.

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

#114

Post by Gunax »

hangonhn wrote: post #98
YetAnotherMatt wrote: post #83

Earlier quoted context omitted.

For almost everyone 18-40 year old, driving less is one of the healthiest decisions you can make. A little nitpick: Motorcycling, cycling, and walking are all significantly worse than traveling by car. If this interests you, it's possible to find a lot more interesting research by searching for "microlife" and "micromort".

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.

My guess is that on a per distance basis, walking is more dangerous because of pedestrian-car collisions (aka getting run over).

I think part of the dissonance is that intuitively I tend to compare on a time basis. I guess it depends on whether one is traveling to a destination (constant distance) or traveling for recreation (constant time).

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

#115

Post by nitrogen »

jbay808 wrote: post #77
globular-toast wrote: post #23

Earlier quoted context omitted.

Presumably downvoted because people don't like it. But it's the truth.

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

I've been riding out the quarantine in a less populated area, and I am surrounded by trucks so tall that the driver can't even see the roof of my car if I am stopped next to them at a light. It's already too late to avoid defection -- if I stay here for good, I will have to get a taller car just so other drivers can see me and so I can see through the windows of parked cars when turning.

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

#116

Post by jandrese »

netman21 wrote: post #44

When I designed car seats we optimized them for the federal tests. The biggest load on a seat back was represented by a large 95% man leaning back to get at his wallet. We were ready for production when the car had it's first sled test. Basically mimic what happens to the occupants when hitting a solid barrier at 30 MPH. The front seat occupants flew forward, bounced back, and completely broke the seat backs, crushin…

That sounds like it was straight up underdesigned. The amount of force in an accident is way higher than a human can normally exert, so designing only for what a human can exert means you were doomed to fail in the accident scenario. The designer forgot to consider the edge cases.

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

#117

Post by Daneel_ »

fractionalhare wrote: post #110
YetAnotherMatt wrote: post #83

Earlier quoted context omitted.

For almost everyone 18-40 year old, driving less is one of the healthiest decisions you can make. A little nitpick: Motorcycling, cycling, and walking are all significantly worse than traveling by car. If this interests you, it's possible to find a lot more interesting research by searching for "microlife" and "micromort".

Is that a typo, or do you teally mean cycling and walking are significantly worse than traveling by car? Are both of those activities actually more dangerous? I would have thought cycling and walking - even in urban settings! - are safer activities than driving, statistically.

I would imagine that it’s not a typo. In a car you have a big shell around you to protect against the environment. While walking or cycling you’re far more prone to be injured by the world - a branch could fall on you, a car could hit you, another person could hit you, you could trip, slip or lose balance, etc.

Being inside a big metal shell that can’t fall over and with active safety measures is a great place to be, risk-wise.

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

#118

Post by jbay808 »

nitrogen wrote: post #115
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.

I've been riding out the quarantine in a less populated area, and I am surrounded by trucks so tall that the driver can't even see the roof of my car if I am stopped next to them at a light. It's already too late to avoid defection -- if I stay here for good, I will have to get a taller car just so other drivers can see me and so I can see through the windows of parked cars when turning.

I know; I've had the same experience. :(

It's a shame. The pedestrians will have to find a way to get taller too.

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

#119

Post by UnFleshedOne »

hangonhn wrote: post #98
YetAnotherMatt wrote: post #83

Earlier quoted context omitted.

For almost everyone 18-40 year old, driving less is one of the healthiest decisions you can make. A little nitpick: Motorcycling, cycling, and walking are all significantly worse than traveling by car. If this interests you, it's possible to find a lot more interesting research by searching for "microlife" and "micromort".

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.

Might have something to do with the size of your signature (I think that's what they call it in military terms).

Consider a spherical traveler following a certain path in a field of randomly moving projectiles. The chances of being hit with one depends on path length, your own size, and how long you stay on the field.

Seriousness of the hit depends on your durability and speeds involved.

Maybe pedestrians just spend a lot of time exposed (assuming they have to cover similar distance) and bikers are extra fragile.

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

#120

Post by apcragg »

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.
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