5 ms·
> If a pedestrian suddenly rushes out into the street or a cyclist swerves into your path, the deciding factor is often simply the coefficient of friction betwe
by zkms 9y ago
> If a pedestrian suddenly rushes out into the street or a cyclist swerves into your path, the deciding factor is often simply the coefficient of friction between your tyres and the road.
This holds iff the control input you apply is only braking. Changing the steering angle is generally far more effective for the "pedestrian darts out from hidden place onto road" situation. It's far better to sharply swerve away to ensure that there's no way the pedestrian can get into your path before your car arrive there than it is to stand on the brakes and hope for the best.
Indeed, the faster you're moving, the more you should consider swerving away over braking -- take advantage of that lethal speed to clear the pedestrian's potential paths before he can get into yours.
Yes, this intentionally violates the letter of the traffic laws (and might involve colliding into a a parked or moving automobile on the other side of the road) and also involves potentially unusual manoeuvring on a very short deadline; but it's far better to avoid a vehicle-pedestrian collision even if it's at the cost of possibly busting into the opposing lane / driving off the road / hitting a parked car. Decently experienced drivers can do this, I can do this (and have successfully avoided a collision with a pedestrian who ran out between parked cars on a dark and raining night), there's no fundamental reason that computer-controlled cars can't do this.
- dsfyu404ed 9y ago>Yes, this intentionally violates the letter of the traffic laws... ...so you probably won't find any support for it in this crowd. > there's no fundamental reason that computer-controlled cars can't do this. Sure, there's no fundamental reason you can't swerve but you need to identify the thing in the road you're trying not to hit before you can decide whether to swerve or brake. Self driving cars can't yet reliably ID things well enough to take the only evasive action they know (stopping).
- tboughen 9y agoI think you touched on the fundamental reason self driving cars cannot currently do this. It would mean programming self driving cars to, in some circumstances, break the law. I agree with the thrust of your comment though, and think that a change in the law may be required to allign incentives for machines as well as people to drive humanely.
- taneq 9y agoThey already do that for speed limits - iirc Waymo cars will 'go with the flow' to a certain extent if everyone around them is speeding. Swerving out of your lane (assuming it is safe to do so) to avoid a collision seems pretty straightforward.
- Piskvorrr 9y agoWhich eventually gets the vehicle into conflict: Exhibit A, amongs other things going over the speed limit, oops, now someone's dead.
- Piskvorrr 9y agoHmm, interesting. Google Street View seems to have 45 mph speed limit at that location...https://www.google.com/maps/@33.4350531,-111.941492,3a,75y,334.17h,76.5t/data=!3m6!1e1!3m4!1sx-K4_17J8MVthFRapvIa2A!2e0!7i13312!8i6656?hl=cs https://www.google.com/maps/@33.4350531,-111.941492,3a,75y,3...
- jessaustin 9y agoThis is a good point. Robocars will have more evidence for their defense in such a case than human drivers would have. "Oh there was a kid who jumped out? And that's why you plowed into this parked car? Likely story!"
- bryondowd 9y agoObviously if there's room and time to swerve and avoid the pedestrian, you should, but swerving into an oncoming car? That sounds extreme. There's no way I'd risk killing myself and anyone in the oncoming vehicle to save one person who made a poor decision. In any situation where there's other traffic and off-street foot traffic, swerving might just cause more harm than good. Everything is situational, and I'm sure there are bound to be cases where there is no sensible option for avoiding a fatality because of exceedingly bad timing on the pedestrian's part.