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Comment by jiveturkey | Hacker News Reader

> If you can't give your "self-driving software" full access to the brakes because it becomes an "erratic driver"

You misunderstood. The Uber software had sole control of the brakes (plus the human of course). The Volvo factory system was disabled so that it didn’t have negative interaction with the Uber system.

Your mistake is understandable. The article was poorly written, perhaps due to a rush to publish, as is the norm these days. Even if the NTSB report was unclear, that doesn’t excuse clumsy reporting.

If you’ve ever done significant mileage in a car with an emergency braking system you probably have experienced seemingly random braking events. The systems favor false positives over false negatives.

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Is that true? A cousin comment appears to indicate Uber had a parallel emergency breaking system and that is what failed to trigger:

> At 1.3 seconds before impact, the self-driving system determined [...]

Unless this is exceptionally poorly worded, it certainly sounds like self-driving system was the one doing the determination.

https://news.ycombinator.com/item?id=17144741

I wrote it carefully and I stand by it. If it can't deal with it because your system is getting too confused for any reason, you don't have a self-driving system. Being able to function enough like a human that the safety features on the car don't produce an unacceptable result is a bare minimum requirement to have a self-driving car.

This isn't horseshoes, as the old saying goes. I unapologetically have a high bar here.

Far as I can tell, the done thing in the industry is to disable all other safety systems (or to not have any in the first place) and to delegate safety entirely to the self-driving AI.

The charitable interpretation of this is that the industry believes that self-driving AI is a safety feature of greater quality than, say, lane assist or auto-breaking.

The less charitable one is that they find it too much work to integrate their AI to other safety systems. Which, to be fair, is really going to be a lot of extra work, on top of developping self-driving.

>You misunderstood. The Uber software had sole control of the brakes (plus the human of course). The Volvo factory system was disabled so that it didn’t have negative interaction with the Uber system.

That's not how I read it, or how any of the journalists who are reporting the story are reading it. Uber disabled the self driving software's ability to do an emergency stop when it detected it was going to crash. The Volvo system is separate and also was disabled when the car was in self driving mode.

https://www.bloomberg.com/news/articles/2018-05-24/uber-self...

>Sensors on an Uber SUV being tested in Tempe detected the woman, who was crossing a street at night outside a crosswalk, eventually concluding “an emergency braking maneuver was needed to mitigate a collision,” the National Transportation Safety Board said in a preliminary report released Thursday.

>But the system couldn’t activate the brakes, the NTSB said.

That's the only reading that makes sense to me, otherwise why did the car fail to attempt to stop when it detected the pedestrian and knew it was going to hit them?

This is from the NTSB report:

"At 1.3 seconds before impact, the self-driving system determined that an emergency braking maneuver was needed to mitigate a collision (see figure 2). According to Uber, emergency braking maneuvers are not enabled while the vehicle is under computer control, to reduce the potential for erratic vehicle behavior."

I believe you are the one who has misunderstood.

I think you're wrong. The Uber software controls the brakes, thru whatever means they're controlling the car. It has to – the car has to stop somehow!

"emergency braking maneuvers" refers to an additional automated (software) system for automatically applying the brakes in an emergency (that's detected by that additional system).

No, see footnote 2 of the NTSB report:

>2 In Uber’s self-driving system, an emergency brake maneuver refers to a deceleration greater than 6.5 meters per second squared (m/s^2).

So, Uber's self-driving system has command to brake normally, but it cannot "slam" the brakes. The other system from Volvo's is deactivated when Uber's is working and cannot brake at all. Thus, since Volvo's is deactivated and Uber's won't brake if it judges that a deceleration of >6.5 m/s^2 is needed, it turns out that in automated mode, the car actually lacks the ability to trigger emergency braking at all, hoping instead that the driver will somehow notice. But in a sadistic twist, no warning is given to the driver at any moment that they need to slam the brakes.

At 1.3 seconds, and with as many false-positives as it sounds like the system has, I don't think a warning would have helped.

No, it would probably take a large part of that time to even react, especially if you are looking at a screen.

However, if the safety driver was trained to brake immediately upon warnings it could have worked quite well. But that would negate the removal of e-brake actuation.....

If the car cannot use emergency braking it could at least decelerate. It looks like some hack where the engineers just commented out the code for brakes and left decision to the driver.

edit: nevermind, see makomk's response to me.

The NTSB report is pretty unclear, I had to re-read it several times and I think you're correct that the "emergency braking maneuvers" they refer to are the Volvo ones. It's strange though that they word it as

> At 1.3 seconds before impact, the self-driving system determined that an emergency braking maneuver was needed to mitigate a collision

Is the Uber self-driving system able to interact with the Volvo system? Or are they calling the Volvo safety features a second "self-driving system"? And what were the steps, Uber realizes it needs an emergency braking maneuver and sends a signal to the Volvo system which then responds with "I'm disabled" ?

I understand why the Volvo features may be disabled, but it's alarming that the self-driving system made no attempt to brake at all when it was fully "aware" it would hit someone.

The report does mention the Volvo braking features by name a few paragraphs earlier though... So I'm still not entirely sure.

They definitely seem to be referring to the Uber self-driving system. The sentence "At 1.3 seconds before impact, the self-driving system determined that an emergency braking maneuver was needed to mitigate a collision (see figure 2)." has this footnote attached to it: "In Uber’s self-driving system, an emergency brake maneuver refers to a deceleration greater than 6.5 meters per second squared (m/s^2)".

Thanks, don't know how I missed that, I'll blame my phone screen haha.

> The vehicle operator is relied on to intervene and take action. The system is not designed to alert the operator.

If what you said is true, then the vehicle operator would not be relied on to intervene because the Uber self-driving software would apply the brakes. Since the vehicle operator is relied on to intervene, this indicates the Uber self-driving software has its emergency braking disabled.

> If you’ve ever done significant mileage in a car with an emergency braking system you probably have experienced seemingly random braking events. The systems favor false positives over false negatives.

This is not my experience with VW's 2016-model-year system.

Soemtimes it stops a second or two before I would've. I haven't had any false positives, though.

Same here in our 2016 wv, we had a beep once for a warning in an intersection with traffic nearby, but never a false positive.

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