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Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

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Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#281

Earlier quoted context omitted.

What speed would you drive? Would you take close corners at 120km/h? People (on average) drive at the speed their actually very well tuned survival instinct tells them to.

I don’t think that’s true at all (though I only have my own experience to go off of). I tend to use the speed limit as a point of reference, and then drive a little above it. Prior experience has told me that going the speed limit plus some percentage ‘feels’ safe. If there were no speed limit I’d actually have to pay more attention to the road and surrounding environment to determine what a safe speed is. Right now…

A book on the topic quotes:

> "Note that the people drive the speed they feel comfortable with regardless of the posted speed limit if enforcement is not present"

- ref: https://books.google.co.jp/books?id=tF7uyw7feOMC&pg=SA13-PA1...

And a paper:

- "PEOPLE DRIVE THE SPEED THEY ARE COMFORTABLE WITH ON GRAVEL ROADS REGARDLESS OF SPEED LIMIT, K-STATE RESEARCHERS SAY"

- https://www.k-state.edu/media/newsreleases/april09/speedlimi...

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#282

Earlier quoted context omitted.

You aren't kidding about it being standard operating procedure. Almost every time a pedestrian or cyclist is killed in New York City, the police come out and blame anyone but the driver. And then video will turn up afterwards showing that the driver was driving unsafely, and that the fatal accident could have been avoided. Still, no charges are filed. It's like they have an allergy to paperwork. I want to see video o…

The difference is that in NYC the cops can get away with that just by taking the surveillance tapes from the local businesses and then destroying them. In this case presumably they know the video will eventually come out.

Are there any reports that NYC police actually do or have done that?

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#283

Earlier quoted context omitted.

What speed would you drive? Would you take close corners at 120km/h? People (on average) drive at the speed their actually very well tuned survival instinct tells them to.

I disagree that the average driver has well-tuned instincts. Accidents are rare enough events that you can drive poorly for a long time and still not end up in a seriously bad situation, especially in areas where inclement conditions are also rare. The first time you lose control of your car might be in icy conditions, and might be not just losing control, but spinning out of control in traffic. The line between in c…

I mean self-preservation instincts, not driving instincts. I agree totally with the later!

By self-preservations instincts what I mean is that most people will try to be as safe as possible on the road, meaning drive slower on low-visibility situations, when there are many pedestrians around, etc. You cannot account on unforeseen circumstances or lack of knowledge, but otherwise people will try very hard not to get into harm's way.

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#284
post #52

> According to the Chronicle, the preliminary investigation found the Uber car was driving at 38 mph in a 35 mph zone and did not attempt to brake. Herzberg is said to have abruptly walked from a center median into a lane with traffic. Police believe she may have been homeless. I know this isn't the most pertinent issue here, but I'm surprised the self-driving AI is allowed to speed , though with further research, th…

Id rather the cars travel at safer speeds than an arbitrary speed limit which is 99% of the time unsafe.

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#285

Earlier quoted context omitted.

Of course a self driving car should be able to speed. My understanding is that speed limits are set by measuring the speed people are driving on the road and then determining a speed at which roughly 15% of the drivers are exceeding that limit. There is an expectation that people will speed, but by setting the speed limit a little bit lower almost all traffic will fall under safe bounds. Driving 38 in a 35 zone is co…

> My understanding is that speed limits are set by measuring the speed people are driving on the road and then determining a speed at which roughly 15% of the drivers are exceeding that limit. That is not how all speed limits are set; it just one possible technique: https://safety.fhwa.dot.gov/speedmgt/ref_mats/fhwasa12004/

Thanks for clarifying, and the link! Actually a really interesting read.

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#286
post #263

Earlier quoted context omitted.

What speed would you drive? Would you take close corners at 120km/h? People (on average) drive at the speed their actually very well tuned survival instinct tells them to.

Without a speed limit, I'd take i-70 from KC to STL at about (160~mph) 250km/h for 95% of it. I'd make day trips just to get white castle at white knuckle speeds.

I don't think that is your average American! At least I hope not ;)

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#287

> “The driver said it was like a flash, the person walked out in front of them,” Moir said. “His first alert to the collision was the sound of the collision.” I don't know if that is supposed to make anyone feel better about this, if anything it makes it seem worse. I thought one of the big benefits of these systems was they were supposed to be better at exactly these kinds of situations? More like "autonomous cars a…

The point is that if someone runs in front of your car, physics dictates that you can't stop a 1,000+ pound vehicle on a dime. You can lock the brakes up and stop the axle from moving (ABS braking won't actually allow this usually) and the car will still continue forward for some time. In addition many other avoidance strategies won't work. Sure, you could swerve, but what's in your path then?

Machines don't get tired or bored, they don't screw around with the radio or put on eyeliner, or get distracted by text messages. They have other issues but we hope they'll be less prevalent.

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#289

My takeaway from the comments in this thread: self-driving Ubers don't drive defensively, almost surely can't "read" pedestrian behavior, and even with lidar may never have seen Elaine Herzberg. Oh, and they speed. This sounds like straight out of the "hell" scenario for driverless cars: "we cannot accept responsibility for what happens to pedestrians and cyclists foolish enough to stray out of their designated safe…

I think you might be confusing "defensively" with perfectly. There are situations even defensive driving cannot prevent. For example, any car going 35 mph will need a few feet to brake if something jumps directly in front of it. Defensive driving just accounts for one's surroundings and likely outcomes. Seeing as the cars have been on the road in Arizona for a while, and this is the first we are hearing about a pedes…

An important observation is that the probability of death drops very rapidly with drops in speed. A rough calculation shows that at 38 mph and a near instant reaction (as a robot should) would within ~1 second of applied breaking force, allow going from a ~70% chance of death to ~5%.

A very rough calculation: v(t) = -μgt + v_0. To reach 32 kph or 20 mph, t ~= 0.82/μ, guessing a fair μ=0.8 and the chart here https://ec.europa.eu/transport/road_safety/specialist/knowle...

Re: Police Say Uber Is Likely Not at Fault for Self-Driving Car Fatality in Arizona

#290

Earlier quoted context omitted.

As another driver on the road, I'd far rather that autonomous vehicles maintain speed with the flow of traffic around them, in lieu of strictly sticking to the posted limit.

There is no traffic "around" them, just the car behind. And if the car behind is speeding it's up to them to slow down if the car in front is obeying the speed limit. This kind of argument is just used to justify speeding.

> There is no traffic "around" them, just the car behind.

How about when merging, or changing lanes? The speed limit is not _always_ safe or practical to obey strictly.

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