How well do cars do in crash tests they're not optimized for? • Hacker News Board

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

#91

Post by loeg » Tue, Jun 30, 2020, 4:50 PM UTC

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.

(Holding the risk per mile driven constant, from current driving patterns. Risk might increase with more drivers on the road, especially given they're all driving ~16 hour shifts.)

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

#92

Post by shoes_for_thee » Tue, Jun 30, 2020, 4:51 PM UTC

ghaff wrote: post #79

baxtr wrote: post #76

Earlier quoted context omitted.

Thanks! That’s really a great source. I am so glad I asked. Highlights: - Fishing seems to be quite dangerous!!?? - Swimming is less dangerous than living (all other causes)!

That the rate (not time based) for fishing is so high does seem a bit odd. I wonder a bit what all is being lumped in there. I assume it's because it's an activity that can involve water, boats, and sometimes alcohol.

Any time you are operating in water, your mode of failure goes from falling to drowning.

Rocks are slippery.

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

#93

Post by ivanbakel » Tue, Jun 30, 2020, 4:51 PM UTC

henryfjordan wrote: post #85

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?

VW actively detected if the car was on a treadmill testing setup and electronically changed the engine parameters to make it run cleaner. The water heater was designed with the test in mind but functions the same regardless. VW was clearly cheating whereas the water heater is taking advantage of known deficiencies in the test (is that cheating?).

What was more heinous about the VW case IIRC is that the cleanliness gains the cars made on the treadmill setup were enough to push them into compliance with regulations, which the engines normally didn't meet.

"Cheating" a better efficiency rating is significantly less reprehensible than cheating a legal obligation which was legislated for public health and environmental reasons.

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

#94

Post by shoes_for_thee » Tue, Jun 30, 2020, 4:52 PM UTC

baxtr wrote: post #76

shoes_for_thee wrote: post #43

Earlier quoted context omitted.

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

Thanks! That’s really a great source. I am so glad I asked. Highlights: - Fishing seems to be quite dangerous!!?? - Swimming is less dangerous than living (all other causes)!

Swimming vs 'living' seems intuitively weird to me too. I guess people who are otherwise in poor health tend to avoid swimming?

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

#95

Post by ebg13 » Tue, Jun 30, 2020, 4:53 PM UTC

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.

So they _intentionally_ set themselves up to lie to regulatory agencies and consumers about real world efficiency. That honestly sounds basically the same to me. In both cases the tests are poor approximations, and in both cases someone could accidentally optimize the test, and in both cases someone did it intentionally to deceive people.

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

#96

Post by bruckie » Tue, Jun 30, 2020, 4:53 PM UTC

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…

What's a 95% man?

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

#97

Post by kube-system » Tue, Jun 30, 2020, 4:54 PM UTC

ghaff wrote: post #79

baxtr wrote: post #76

Earlier quoted context omitted.

Thanks! That’s really a great source. I am so glad I asked. Highlights: - Fishing seems to be quite dangerous!!?? - Swimming is less dangerous than living (all other causes)!

That the rate (not time based) for fishing is so high does seem a bit odd. I wonder a bit what all is being lumped in there. I assume it's because it's an activity that can involve water, boats, and sometimes alcohol.

Even if you're on the shore it's easy to slip and hit your head on a rock. Also, many other sports that are listed self-select for athleticism or physical ability.

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

#98

Post by hangonhn » Tue, Jun 30, 2020, 4:55 PM UTC

YetAnotherMatt wrote: post #83

dublinben wrote: post #12

Earlier quoted context omitted.

You're right that there aren't meaningfully significant differences between car brands. Driving itself is just very dangerous. Other forms of transportation like buses, trains, and airplanes are orders of magnitude safer.[0] If you want to make yourself safer, avoid driving as much as possible. [0] https://injuryfacts.nsc.org/home-and-community/safety-topics...

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.

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

#99

Post by ebg13 » Tue, Jun 30, 2020, 4:56 PM UTC

ivanbakel wrote: post #93

henryfjordan wrote: post #85

Earlier quoted context omitted.

VW actively detected if the car was on a treadmill testing setup and electronically changed the engine parameters to make it run cleaner. The water heater was designed with the test in mind but functions the same regardless. VW was clearly cheating whereas the water heater is taking advantage of known deficiencies in the test (is that cheating?).

What was more heinous about the VW case IIRC is that the cleanliness gains the cars made on the treadmill setup were enough to push them into compliance with regulations, which the engines normally didn't meet. "Cheating" a better efficiency rating is significantly less reprehensible than cheating a legal obligation which was legislated for public health and environmental reasons.

But the efficiency ratings also exist for public health and environmental reasons. Why does it matter to you that one is a mandate? They're both intentionally deceiving regulators and consumers (vs accidentally acing the test without cheating). Both are fraud.

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

#100

Post by ballenf » Tue, Jun 30, 2020, 4:57 PM UTC

yboris wrote: post #24

JoeAltmaier wrote: post #17

Earlier quoted context omitted.

Drive the largest vehicle you can. When in a collision the momentum is converted to crushing force, you want to be in the less-crushable vehicle. Hey this may be an unpopular choice, but it is the one with the biggest safety impact! And that was the question.

Rather immoral. Not just offloading, but also exacerbating the burden onto others. Vehicles and Crashes: Why is this Moral Issue Overlooked? by Douglas Husak https://www.jstor.org/stable/23562447?seq=1

The free preview of your citation seems to propose legal liability for drivers of vehicles that cause outsize risk to others.

Safety equipment inside cars does the same -- people who feel more safe in their car drive more dangerously and take more risks. Maybe that's addressed in the full article.