Hacker News Reader

Comment by andreashansen | Hacker News Reader

Agreed. I remember attending a presentation by Google regarding their self-driving cars. What they told us fascinated me. Their last main hurdle is ethics, and they used to following scenario to illustrate:

Two motorcycles are coming towards the self-driving car, and the car is forced to crash into one of them. One of the motorcyclists is not wearing his helmet, and there's a definite chance of fatal injury if crashed into by a car. By not wearing his helmet, he is also breaking the law.

The other motorcyclist is wearing her helmet, and there's less of a chance of fatal injuries.

Should the self-driving car crash into the law-abiding motorcyclist who is doing everything right but with a less chance of fatal injuries, or into the irresponsible non-helmet wearing motorcyclist where injuries could be fatal?

That's the kind of scenarios they have to deal with. The technology however, works.

View on HN

This is called the "trolley problem". Here's a good read about that: https://backchannel.com/reinventing-the-trolley-problem-85f3... TLDR: such a scenario will NOT happen. A computer is not likely at all to find itself in such a situation. My opinion: study of such scenario is there just to give more confidence into self driving cars. Just to show people "See? We thought hard about this. Trust autonomous vehicules".

The answer to almost all of these hypothetical problems is "hit the brakes". Speed is the main killer in automobile accidents, it's a power law. Just a small reduction in velocity can have a dramatic impact on the survivability of an accident.

What about the question of whether to swerve into traffic to avoid a kid who ran into the street from between two parked cars?

Answer: you were going too fast to begin with. If you're travelling anywhere that this is a possibility, your maximum speed should be less than 20mph. A collision at that speed is almost never fatal. That speed also allows almost instant braking.

The fact that autonomous cars will be driving so slow and defensively in the suburbs will perhaps be the biggest cause for the coming backlash against them.

We're talking about exceptional circumstances. With hundreds of millions of autonomous vehicles on the road, 1 in a billion is next Tuesday. We can minimize the need for this decision, but leaving the behavior undefined will just lead to headaches when it does happen.

We have currently ~30,000 fatalities in a year. What portion of these are trolley problems? Less than 1 in a million, I'd bet. What percentage of those trolley problems are entirely avoidable through proper defensive driving techniques?

Neither. Either pick the route most likely to avoid a head on collision if the motor cyclists also swerve, or just pick a path at random if all of them result in collisions. Trying to build in ethical rules is a fool's errand because you'll never get it right and might even create additional legal liability due to the rules chosen.

... or do not play God at all. (Edit: This is also an ethical choice)

Just drive safely. Keep your distance and be very good at reducing your own speed as fast and as safe as possible.

Even in this hypothetical it will certainly help reducing the speed as the motorcycles will have a better chance to react.

Presumably it would plug into legal data to estimate which option would be less financially risky to the car company.

Or should the Self driving car take into account that the passenger of the self driving car is, hypothetically, a male in his 60s who has raised his children already, and crash himself into the wall or drive off the cliff avoiding both of them, who are younger men with young children to raise?

Crash into both of them, problem solved. Or just pick one at random.

Reply on news.ycombinator.com