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Effects of large vehicles on pedestrian and pedal-cyclist injury severity

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201–210 of 278 posts

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#201
post #62
post #47

Earlier quoted context omitted.

The odds are in your favor to be honest. I live in a city of 4 million people. 10-20 cyclist die a year. I'll roll those dice when the variance is that high. I figure I bike safer than the average biker I see on the road anyhow, so my odds of survival go up even higher. Probably not a small number of those accidents involved intoxicated bikers or mentally ill; I see a lot of people, clearly out of their mind through…

Something else that improves your QALYs: cycling. Of course, it's about exercise more generally, but if you don't have time to exercise only, doing it while commuting is clever! In most locations in the world -- my null hypothesis includes the US here too -- people who commute by bike (for all its risks) live longer and are sick less than those who do not.

I probably would have given this a full-throated endorsement just a couple years ago, but after years of improving safety standards that drove down the number of automobile fatalities, we've seen two years of massive increases (7% in 2020 and then 10% last year [0]). And that pairs nicely with my anecdotal experience, which is that people have lost their fucking minds on the roads. (And also, more controversially, coincides (with utter predictability, in my view) with a massive drop in traffic stops by law enforcement.)

[0] https://en.wikipedia.org/wiki/Motor_vehicle_fatality_rate_in...

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#202

Earlier quoted context omitted.

With three kids and car seats/boosters, there is no option. You need a minivan or SUV.

So you're saying all those five-seater cars that are being made are for seating five adults but if you have children you need a van?

Yes. If you have 3 kids and 2 are in the booster seat category, which some agencies recommend until they are 4'9" (145 cm), which some kids may not reach until 12 or older. You cannot fit 3 large booster seats in a Golf, or at least not comfortably.

I personally doubt the necessity of booster seats for older children at all but that's another topic all together.

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#203

Earlier quoted context omitted.

Vans are nightmare stuff for motorcyclists. Hitting a compact car from most angles means rolling over it. Hitting a van from any angle is instant SPLAT - all potential energy gets instantly converted into damage. We don't have SUVs here (Eastern Europe), but I think they're a closer to vans than to compacts.

Sorry dude I've got 4 kids, there isn't a sedan out there that I can fit 4 car seats in, and still have room for a driver and passenger.

But at least a 6 seat Tesla Model X would probably hurt pedestrians less compared to a “van”?

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#204
post #91

Earlier quoted context omitted.

Radu, I'm Romanian too (and assuming based on your name you're Romanian), we have lots of SUVs. Maybe you're thinking of something else? Maybe pickup trucks?

I meant F-150 style cars. They're next level - much taller and wider than what we have here. Small 4x4s like Toyota RAV4 are closer to compacts, and you still have a fair chance to roll over if you hit them in the front. I guess we do have larger 4x4s like Land Cruiser, forgot about them. They're somewhere in between? Wouldn't want to hit one, but it's not a guaranteed "splat".

When articles like this talk about SUVs, in includes autos like the RAV4. Those smaller SUVs are one of the biggest growth areas for manufacturers

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#205
post #163
post #34

Earlier quoted context omitted.

Its the momentum that kills you p=mV, not the kinetic energy. So I would guess that mass ia much more important.

You are both wrong, It's the acceleration that kills you.

Doubling the mass of the car assuming everything else (crumple zones etc.) stays the same - doubles the acceleration experienced by the pedestrian.

    X_p0 = X of the pedestrian before collision
    X_c0 = X of the car before collision
    X_p1 = X of the pedestrian after the collision
    X_c1 = X of the car after the collision
    m_ = mass
    v_ = velocity
    a_ = acceleration
    t = time

    //conservation of momentum:
    m_p * v_p0 + m_c * v_c0 = m_p * v_p1 + m_c * v_c1
    m_p * (v_p0 - v_p1) = m_c * (v_c1 - v_c0)
    v_p1 - v_p0 = m_c * (v_c0 - v_c1) / m_p

    // a = delta v / t
    a = (v_p1 - v_p0)/t = m_c * (v_c0 - v_c1) / (m_p * t)

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#206
post #163
post #34

Earlier quoted context omitted.

Its the momentum that kills you p=mV, not the kinetic energy. So I would guess that mass ia much more important.

You are both wrong, It's the acceleration that kills you.

Acceleration, which is caused by a transfer of energy?

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#207
post #169

As an American, we need to rethink how the cities are designed. Way too much emphasis on car centric design. An emphasis on car centric transportation means fed government and people want cars to be safer. Larger A-pillars which decrease line of sight. Larger vehicles give people a higher sense of security and safety. These 2 points make it very safe for the driver and occupants but disregard any safety for pedestria…

The American system is broken. Many (Blue) states would happily rein in oil guzzling pickups, SUVs, etc but Federal law prevents that. Another example is states can't require truck trailers to have side barriers to keep small cars and cyclists from going under.

Interestingly, California has essentially put itself in the position of dictating emissions standards for the entire USA because it imposes the strictest requirements, and California is a large enough market that carmakers won't ignore it (but small enough that it's not worth separate SKUs).

I wonder what would happen if California, or New York, or a consortium of smaller blue states like New England imposed safety standards that banned or heavily penalized trucks and SUVs over 4,000 lbs, oversized A pillars, etc.

Would the automakers blink, and start making cars safer? Or would they just start selling the dangerous vehicles only in red states? Would blue states start to ticket dangerous vehicles purely for existing on roads?

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#208

Earlier quoted context omitted.

Sorry dude I've got 4 kids, there isn't a sedan out there that I can fit 4 car seats in, and still have room for a driver and passenger.

But at least a 6 seat Tesla Model X would probably hurt pedestrians less compared to a “van”?

Be serious. That's a $100k car. This person has 4 kids.

Re: Effects of large vehicles on pedestrian and pedal-cyclist injury severity

#210

The sad thing is that at least some part of the growth of vehicles on the road is because few people can afford to own (and park) multiple cars or other vehicles larger than a bike. I have to move 3 kids and 2 adults regularly over longer distances, so I am pretty much constrained to a van (say a VW T7). But unfortunately, I cannot afford to accompany this expensive car with a smaller, preferrably electric, vehicle.…

The distance is a choice, mind you. One cargo bike for each adult would otherwise handle the job fine
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