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A car going at 5mph is still going to kill or main a pedestrian if it hits them. I agree that speed and general "cars forever!" approach is not great, but ther

A car going at 5mph is still going to kill or main a pedestrian if it hits them. I agree that speed and general "cars forever!" approach is not great, but there is always room for improvement ... e.g. could tech have saved that 1 person who died in Oslo? Why just stop at "the Oslo model"? Why not do that and autonomous tech? It would be worth it if it saved just a handful of lives a year.

ashtonkem 6y ago
Obviously cars and pedestrians should be separated, but you are dramatically understating the impact speed has on pedestrian survival rates. At 5mph your chance of surviving a collision is extremely high. Heck, you have a 93% chance of surviving a 20mph crash, depending on your age. Survival rates drop off quickly with speed however, with only 80% surviving at 30mph, and 45mph being a 50/50 chance for most of the population. The effect is that slowing cars down from 35mph to 20mph in areas where pedestrians are close to cars could potentially double the chance of a pedestrian surviving a crash. And that’s not even accounting for how much less likely a collision is to happen at 20mph than 35mph. Source: https://www.propublica.org/article/unsafe-at-many-speeds https://www.propublica.org/article/unsafe-at-many-speeds Edit: of course, we can and should add more tech to make cars safer. That’s why backup cameras and seat belts are mandatory, and that’s a good thing. But as an argument for self driving cars, I think that they really come up short when there are tons of effective strategies available right now that we aren’t applying. And that’s my point.
- jdxcode 6y ago
  that makes sense given kinetic energy is mass * velocity^2. That squaring of velocity means every mph as they get higher is even more significant than the ones before.
MiroF 6y ago
> A car going at 5mph is still going to kill or main a pedestrian if it hits them. what?
- nogridbag 6y ago
  I think this happens fairly often in Manhattan. There's lots of box trucks simply making turns at 5mph and pedestrians crossing obliviously with headphones on or looking at their phones.
  - ashtonkem 6y ago
    Vehicle weight has a large impact on survivability, but not all the way down at 5mph. Plus, vehicles are easy to avoid at 5mph, the majority of the human population can out walk cars at that speed. That being said, vehicle size is another uncomfortable subject when it comes to road deaths. If we really cared about not killing people on the road, we’d take a long, hard look at what cars we allow to operate on our roads. Delivery trucks have the benefit of being obviously necessary; I am glad that trucks exist to deliver my food from the train depot (ideally) to my grocery store. But what’s the argument for Suburbans? SUVs not only drastically increase the risk for pedestrians, but they also make the roads more dangerous for other drivers to. For what? Status? A false perception of safety?
  - smabie 6y ago
    Do you realize how slow 5 mph is? There's no way it could kill anyone, even if they're completely not paying attention.
bobthepanda 6y ago
> I agree that speed and general "cars forever!" approach is not great, but there is always room for improvement ... e.g. could tech have saved that 1 person who died in Oslo? Why just stop at "the Oslo model"? Why not do that and autonomous tech? It would be worth it if it saved just a handful of lives a year. The problem is twofold: 1. Cruise and co. may very well run out of money before they develop tech reliable enough to save people en masse. One proposal decades ago to solve the cars vs people problem was to physically grade separate them entirely, but as it turns out building multistory streets doesn't scale very well. 2. People and politicians, today, are using self driving cars as the magic bullet to avoid spending money on other solutions and changing bad habits. Why spend money on rail or buses if the second coming of Jesus for cars is around the corner? And to a degree, there is an opportunity cost to spending money on unproven X rather than proven Y.
staticassertion 6y ago
5MPH is roughly as fast as a brisk walk... it should not kill anyone.
mattlondon 6y ago
Since I can't edit this: It is not just the energy involved from 5mph - not every accident is a cut and dry collision. A car doing 0.5mph still going to crush your skull when you go under the wheels. People are killed frequently in London (and I am sure other places) when they are crushed by slow moving vehicles turning left or right and the driver just did not see the person there and they are either slowly run-over and pinned between the vehicle and something else and crushed.
- ashtonkem 6y ago
  Yes, people do get crushed under the wheels of slow moving cars. But the statistics are extremely clear about what your relative chances of survival are based on vehicle speed. To a first order approximation your chance of being killed by a 5mph car is 0%. Should we add tech to prevent these accidents? Of course. But let’s not kid ourselves about the actual numbers of where and why cars kill people. As a means of comparison; back up cameras are mandatory to prevent children from being backed over at slow speed. This is an obvious improvement, but numerically quite small, with estimates being that it saves about 50-70 lives nationally per year. This is far less than the number of pedestrians and cyclists struck and killed in Los Angeles per year alone.
- watwut 6y ago
  A car doing 0.5mph will be stopped by the driver unless the driver is unconscious.

ashtonkem 6y ago

Obviously cars and pedestrians should be separated, but you are dramatically understating the impact speed has on pedestrian survival rates. At 5mph your chance of surviving a collision is extremely high. Heck, you have a 93% chance of surviving a 20mph crash, depending on your age. Survival rates drop off quickly with speed however, with only 80% surviving at 30mph, and 45mph being a 50/50 chance for most of the population. The effect is that slowing cars down from 35mph to 20mph in areas where pedestrians are close to cars could potentially double the chance of a pedestrian surviving a crash. And that’s not even accounting for how much less likely a collision is to happen at 20mph than 35mph. Source: https://www.propublica.org/article/unsafe-at-many-speeds https://www.propublica.org/article/unsafe-at-many-speeds Edit: of course, we can and should add more tech to make cars safer. That’s why backup cameras and seat belts are mandatory, and that’s a good thing. But as an argument for self driving cars, I think that they really come up short when there are tons of effective strategies available right now that we aren’t applying. And that’s my point.

jdxcode 6y ago
that makes sense given kinetic energy is mass * velocity^2. That squaring of velocity means every mph as they get higher is even more significant than the ones before.

MiroF 6y ago

> A car going at 5mph is still going to kill or main a pedestrian if it hits them. what?

nogridbag 6y ago
I think this happens fairly often in Manhattan. There's lots of box trucks simply making turns at 5mph and pedestrians crossing obliviously with headphones on or looking at their phones.
- ashtonkem 6y ago
  Vehicle weight has a large impact on survivability, but not all the way down at 5mph. Plus, vehicles are easy to avoid at 5mph, the majority of the human population can out walk cars at that speed. That being said, vehicle size is another uncomfortable subject when it comes to road deaths. If we really cared about not killing people on the road, we’d take a long, hard look at what cars we allow to operate on our roads. Delivery trucks have the benefit of being obviously necessary; I am glad that trucks exist to deliver my food from the train depot (ideally) to my grocery store. But what’s the argument for Suburbans? SUVs not only drastically increase the risk for pedestrians, but they also make the roads more dangerous for other drivers to. For what? Status? A false perception of safety?
- smabie 6y ago
  Do you realize how slow 5 mph is? There's no way it could kill anyone, even if they're completely not paying attention.

bobthepanda 6y ago

> I agree that speed and general "cars forever!" approach is not great, but there is always room for improvement ... e.g. could tech have saved that 1 person who died in Oslo? Why just stop at "the Oslo model"? Why not do that and autonomous tech? It would be worth it if it saved just a handful of lives a year. The problem is twofold: 1. Cruise and co. may very well run out of money before they develop tech reliable enough to save people en masse. One proposal decades ago to solve the cars vs people problem was to physically grade separate them entirely, but as it turns out building multistory streets doesn't scale very well. 2. People and politicians, today, are using self driving cars as the magic bullet to avoid spending money on other solutions and changing bad habits. Why spend money on rail or buses if the second coming of Jesus for cars is around the corner? And to a degree, there is an opportunity cost to spending money on unproven X rather than proven Y.

staticassertion 6y ago

5MPH is roughly as fast as a brisk walk... it should not kill anyone.

mattlondon 6y ago

Since I can't edit this: It is not just the energy involved from 5mph - not every accident is a cut and dry collision. A car doing 0.5mph still going to crush your skull when you go under the wheels. People are killed frequently in London (and I am sure other places) when they are crushed by slow moving vehicles turning left or right and the driver just did not see the person there and they are either slowly run-over and pinned between the vehicle and something else and crushed.

ashtonkem 6y ago
Yes, people do get crushed under the wheels of slow moving cars. But the statistics are extremely clear about what your relative chances of survival are based on vehicle speed. To a first order approximation your chance of being killed by a 5mph car is 0%. Should we add tech to prevent these accidents? Of course. But let’s not kid ourselves about the actual numbers of where and why cars kill people. As a means of comparison; back up cameras are mandatory to prevent children from being backed over at slow speed. This is an obvious improvement, but numerically quite small, with estimates being that it saves about 50-70 lives nationally per year. This is far less than the number of pedestrians and cyclists struck and killed in Los Angeles per year alone.
watwut 6y ago
A car doing 0.5mph will be stopped by the driver unless the driver is unconscious.