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Comment by URSpider94 | Hacker News Reader

Your concept that there are no accidents, only oversights, is not correct. Say I’m crossing the street and I don’t see your car coming, because I look the wrong way or I’m distracted, or my view is blocked by the sun. You may not be able to avoid hitting me.

Additionally, if we train self-driving cars to always give way to pedestrians who even look like they might cross the street, they’re going to have a heck of a time getting through cities. Kids are going to learn that they can trigger a squealing emergency stop by lunging towards the curb - great fun!

What I think WILL happen is that autonomous cars will have to buy blanket insurance policies that cover their entire fleet. High accident/fatality rates will result in high insurance premiums, which will put bad actors out of business.

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I think your first paragraph is written from the perspective of a human driver. The machine can predict based on physics. If anything a person who does not see a car will be more predictable, not less, as they will tend to be moving uniformly and not taking evasive action.

Taking into account optimal (computer driven) car stopping distances, the maximum acceleration of a person and typical pedestrian densities, I don't think getting though cities would be an issue, especially outside the CBD. Even in areas with very high pedestrian traffic cars will be able to get though. In support of this argument, I offer today's "shared" pedestrian zones, where cars and people mix. Pedestrians have right of way, cars are limited to 10km/h, but the cars manage to get though without injuring anyone. Cars would naturally do high speeds on main roads with low pedestrian density and lower speeds (with very short stopping distance) at high pedestrian density.

Why should children have a propensity to intentionally jump in front cars above and beyond anyone else? That's bias.

If anyone intentionally jumped in front of a car then it would be covered by the exemption that I proposed: that the car would not be liable if intent could be proved. Based on the car's sensor logs it would be pretty easy to prove that someone intended to get hit. If the car managed to stop and the person ran away it would then be relatively easy to track that person down based on the logs and charge them with a crime. In any case, I think that that is a hypothetical situation which is unlikely to occur. For the vast majority of people self preservation would trump the desire to cause trouble by putting oneself in a terrifying and life-threatening situation, so I think it would be negligibly rare.

My point is not that children would jump in front of cars. It’s that they would run toward the curb with a heading and velocity that would dictate a collision, then stop just before entering the street. They would do it for the main reason that children do things - because it would be hilarious to watch self-driving cars leave a patch on the road and jerk their passengers back with seatbelt pretensioners. If you don’t actually set foot in the street, you’re not breaking the law.

Changing the average travel speed from 45 kph (the city-wide speed limit in New York) to 10 kph would be a disaster.

In most countries obstructing the flow of traffic, no matter the method, is illegal.

And what alternative do you suggest? Not braking?

For your consideration: https://www.google.com/amp/s/spectrum.ieee.org/cars-that-thi...

This makes no sense.

If I see a kid running towards the road, I'm going to slow or stop my car. I'm not going to think "oh it's just a kid being a jerk, they'll definitely stop before the road" because I don't want to run the risk of squashing a kid.

Therefore, I behave exactly the same as a cautious AI would be expected to behave.

So, why aren't kids running to the edge of the sidewalk when I'm driving?

> Your concept that there are no accidents, only oversights, is not correct. Say I’m crossing the street and I don’t see your car coming, because I look the wrong way or I’m distracted, or my view is blocked by the sun. You may not be able to avoid hitting me

Solvable by reducing speed sufficiently. It's reasonable to expect the car to avoid a man travelling at 10kph from any off-road blind-spot, and a car travelling at 100kph from any on-road blind-spot.

> Additionally, if we train self-driving cars to always give way to pedestrians who even look like they might cross the street, they’re going to have a heck of a time getting through cities. Kids are going to learn that they can trigger a squealing emergency stop by lunging towards the curb - great fun!

If you sprint to the curb in front of traffic today, drivers will stop/swerve. Almost certainly illegal too.

My interpretation of the parent post is that more responsibility can be put on the car to avoid accidents, than is currently the case today. Hence greatly increasing road safety. It sounds great!

It’s not a blind spot I’m worried about. People frequently walk at full speed up to the edge of the sidewalk, then stop just before they would walk into traffic. Should an autonomous car assume that any pedestrian walking towards an intersection is going to continue into the roadway, even if they don’t have the right of way? That’s not what a human driver does.

Likewise, I can be standing still with my toes on the curb, and then lunge into the street. Should a self-driving car assume that every pedestrian standing at a crosswalk could walk into traffic at any moment, and slow down accordingly? Again, that’s not what human drivers do.

There are a number of surface streets near my house with speed limits of 45 mph, and crosswalks every 1/8 mile or so. Requiring cars (autonomous or not) to avoid any possible pedestrian incident at every such intersection would be a disaster for traffic throughout and a huge step backwards.

> That’s not what a human driver does.

A human should be aware that these pedestrians might enter the roadway. The human should perceive those pedestrians as a risk, and be ready to take action.

> Should a self-driving car assume that every pedestrian standing at a crosswalk could walk into traffic at any moment,

Yes.

> and slow down accordingly?

This doesn't follow. The car don't need to slow down. It does need to be ready to perform an emergency brake.

My bigger point, which is getting lost, is that there are rules to traffic (pedestrian, bike and auto) that we are all expected to obey. I do not agree that we can simply assume that a self-driving car assumes all liability for any accident (which is what the parent to my original comment posited). The rules of the road let us operate vehicles at tolerances that make it physically impossible to avoid every kind of collision - for example, as I’ve mentioned, a pedestrian that suddenly sprints into cross traffic traveling 40 mph.

I fully agree that autonomous vehicles can and should do everything they can to avoid accidents. We are in violent agreement there. However, I also think that if we set some kind of unrealistic standard for safety, then we are going to make self-driving vehicles completely unappealing to everyone, because they are going to drive like a cross between my grandmother and a startled squirrel.

This is not a new idea of mine - the issue of the too-polite autonomous car has been extensively studied and reported on. See https://www.google.com/amp/s/mobile.nytimes.com/2015/09/02/t... for just one example.

> they are going to drive like a cross between my grandmother and a startled squirrel.

That genuinely might not be a bad thing, at least in the initial phases. They should be ruled by an abundance of caution until we're sure they can actually make more aggressive decisions.

Uber seems to be defaulting to maximum aggression from the outset, which is hardly surprising from them, but seems extremely over-confident (in fairness, like most new drivers are ;)

> is that there are rules to traffic (pedestrian, bike and auto) that we are all expected to obey

The point of defensive driving is that you can't rely on other people not to be incompetent.

You have a green signal at a traffic light. That does not mean "go", it means "proceed with caution".

> Kids are going to learn that they can trigger a squealing emergency stop by lunging towards the curb - great fun!

Isn't that already the case (and arguably they'd get more satisfaction out of it in some cases by seeing an annoyed driver)? Further, I'd say that's what _should_ happen -- if someone looks like they are going to enter the road, you stop.

You're suggesting that self-driving cars may have to drive slowly and carefully in cities. I don't really see a problem with that. Pedestrians aren't frequently in the immediate vicinity of roads with limits higher than 35mph in my experience. Any human driver has to drive cautiously in the vicinity of pedestrians anyway, if they don't want to risk manslaughter. I'd want SDVs to do that too.

Slowly and carefully, yes. Assuming that any pedestrian could leap in front of your car in violation of traffic laws - no.

Where I live in California, there are two major streets with crosswalks in regular use, with speed limits of 40 mph or higher (and travel speeds of 50+ mph), within a quarter mile of my home.

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