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Comment by kragen | Hacker News Reader

These cars need an emergency stop button which brings the car to a halt as fast as could plausibly be safe and then opens the doors. This is standard equipment on all industrial machinery and used to be standard equipment on all trains as well; I got into a lot of trouble once for pulling the emergency stop cord on a train when I was young. The inconvenience and occasional danger of unwarranted emergency stops is almost certain to be outweighed by the lives saved in the rarer cases where the E-stop is necessary.

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> I got into a lot of trouble once for pulling the emergency stop cord on a train when I was young.

You are the hero of every young child that has ever been on a train and wondered what would happen when they pulled that cord. I know that certainly was a dream of mine when I was four or so. I couldn't understand why my dad was so insistent I not try it.

Presumably opening the door would stop it? I would hope that would be something they thought about and do not lock the passengers in...

I wouldn't assume anything about a modern system

He said "I can't get out the car", which suggests otherwise.

Maybe he was afraid to try because he thought that opening the door of a moving car would be dangerous? It is.

There was no emergency! The car wasn't "spinning", it was just driving around a parking lot and failing to find a location to stop. This was a navigation failure, not a control failure. And the solution is to call the human operators who can control it remotely. Which is what happened, and they did. Pulling an "emergency stop" level would have made things worse and not better.

Is it embarassing for Waymo? Sure. But the BBC basically lied to you here, and you bought it. The circumstance you're imagining is not what happened. Just watch the video.

So if there is no connectivity?

Presumably it pulls over and stops if the backend connection drops, no? This is a kind of goalpost motion: you're countering an argument about an incorrectly-identified failure mode by positing that the condition would still obtain if there was a dual mode failure instead (i.e. that the car would get stuck in a navigation loop and have a bug in its recovery from connectivity issues).

That's bad engineering, because you can always get to some kind of catastrophe if you keep piling on layers. Might as well just skip to "What if the motor circuit fails open and it accelerates forever?!" in that case.

An E-stop button would also solve the problem of the motor circuit failing closed, causing the kind of uncontrolled acceleration you're talking about.

Uh, that was sarcasm. Unintended acceleration failures are huge deals in the industry and absolutely already designed in with multiple (probably dozens) of layers of safety/redundancy at all levels up to and including human control. The point was that you can still imagine a N-mode failure that defeats all of that and use it to justifify whatever whizgig you're demanding in your local internet discussion. And that this was ridiculous, because that's not how you do engineering.

And... you did.

Yes, you can always imagine failures that disable your failsafes. But you seem to be using that as an excuse for advocating omitting even basic failsafes. That's also not how you do engineering.

i am not sure i would say it was "just driving around a parking lot" it was not spinning but it _was_ just going in circles, watch the steering wheel and the background.. right turn pause right turn pause etc you see the same buildings etc. my spouse would have probably barfed all over that back seat

I wasn't imagining a car spinning out of control. Being trapped inside a car indefinitely is dangerous: you could get carsick and have to throw up, urgently need to use a restroom, have a painful leg cramp that causes a lasting muscle injury, miss picking up your child from school, miss your appointment with your probation officer, be unable to obtain essential medication, suffer from heatstroke, or die of dehydration. An adult should never need to "call human operators" and ask their permission to get out of a car. Unless they're being arrested or something.

And if you hear that the car has run over a child that the operator didn't notice and is dragging it down the pavement under the car, it's essential for you to be able to hit the E-stop button rather than calling an operator to eventually stop the car.

> Being trapped inside a car indefinitely is dangerous

It was like two minutes, tops. Again, it's on video!

And I love that you started from a position of needing an emergency escape button and when challenged it's... because the occupant might have to pee really bad.

By lying about my comment, you are really starting to exhaust the presumption of good faith.

You literally argue in this thread that "These cars need an emergency stop button" because the occupants might "urgently need to use a restroom". I cherry picked that because it's hilarious, but it's not a lie and you know it. Those quotes are real: those are your words.

Accusing other people of lying when they point out your whoppers is... not good faith argument.

Your comment asserted that that was the only justification I gave. Even if that were true, it would still make you the kind of asshole who makes fun of elderly women with incontinence problems—in fact, who advocates omitting basic safety features from engineering designs because you think it's hilarious when elderly women with incontinence problems wet their pants. Or, interpreting your comment with more charity than the annual UNICEF budget, you think it would be hilarious if elderly women with incontinence problems had to pull down their pants and pee on the passenger seat.

But it's not true, which makes you a liar as well.

Comments like that one undermine my faith in the capacity of humanity for goodness. You managed to combine dishonesty, unprovoked rhetorical aggression, engineering irresponsibility, and fantasies of a breathtaking degree of sadism into a few short lines. It's honestly one of the most contemptible comments I've ever seen on HN.

> Your comment asserted that that was the only justification I gave.

It certainly did not. It's right up above, please re-read.

Just stop. You got yourself into an embarrassing situation with an untenable argument and are behaving badly, calling your fellow posters liars and assholes.

> the solution is to call the human operators who can control it remotely

Sounds like a recipe for failure, to be honest. In a potentially life or death situation, the last thing I want is to rely on a remote human being. Plus, if the device entered an erroneous state, I certainly don't trust it to correctly interpret a remote "emergency stop" signal.

If the machine goes crazy (and there is no world where driving around a parking lot until the end of time is the rational expected behavior), the only safe option is a big, red, cut-circuit emergency stop button.

I agree. Unfortunately just cutting circuits isn't enough; you also need to brake and possibly unlock the doors.

> In a potentially life or death situation

Which, once more, was not happening here. The car was lost, not out of control. And the built-in solution was applied, and worked.

What do you really want here? You've never been in a Uber that took a wrong turn? Never argued with a cab driver about a route? Never been stuck in an airliner at the end of a runway waiting for clearance? Vehicles do things their occupants don't like all the time, and no one freaks out on the internet about it.

If a cab driver or Uber driver locks you into their car and doesn't allow you to get out, that's "false imprisonment", a felony in most jurisdictions, carrying a sentence of several years of prison. It is very unusual for them to even lock the doors such that you need their help to open them. The last time I had to open an Uber door in a moving car to force the driver to stop—because he'd lied about having air conditioning to get the fare—was two weeks ago.

Airliners are legally required to have emergency exit doors that can be activated by anyone inside the airliner as long as the cabin isn't pressurized. You also know, before you board the airliner, that you won't be able to get off it for several hours. So, if you have an appointment with your probation officer in half an hour or need to pick up your kids from school in half an hour, you won't board in the first place.

You're apparently arguing that passengers of self-driving cars should not have the same legal and mechanical protections that the passengers of these other types of vehicles have.

I'm not saying it was happening here, I'm just taking this anecdote as food for thought. I'm appalled to learn that those vehicles don't have an emergency stop system. A real emergency stop. Not some remote-controlled or AI-assisted stuff. A low-tech, last-chance emergency stop, like the one you have in trains or on any industrial machine.

> You've never been in a Uber that took a wrong turn? Never argued with a cab driver about a route?

If a cab driver keeps cricling on a parking lot, again and again and again, never finding the obvious exit, I'll get a bit concerned and eventually tell him "OK, never mind, I'll find another way, just drop me there". If he refuses to let me off, and locks the doors, and keeps circling, I'll be extremely anxious. This is horror movie material.

> I'll get a bit concerned and eventually tell him "OK, never mind, I'll find another way, just drop me there".

Isn't that exactly what happened here? Rider pushed the help button, got help, and was dropped off. Right there.

I think you get to the truth of the matter with your "horror movie material" quip. You don't think this situation was dangerous. You think it was scary because of the robot. Well, OK. But that's not a safety argument.

One problem is if you are on a freeway, you can't just stop.

Also passenger might be inebriated and randomly push the button.

While I agree with you on principle, it's a hard problem to solve.

Yes, I agree that pushing the E-stop button is not free of risk. But it's a risk under the control of the person who will suffer most of the consequences.

That's not true. If you're on the freeway you could wind up killing multiple people behind you. It could be extremely dangerous.

> It could be extremely dangerous.

You are on a beta, experimental, self driving vehicle. The time to update your life insurance has passed.

No, I'm driving normally at 50 in the rain or whatever and some AI hype-wagon in front of me has slammed on the brakes and swerved across my lane.

The CEO of HypeAI releases a heartfelt video in which they say they are truly sorry for my family's loss and by way of compensation offers them unlimited credits for HypeRides in select US cities conditions apply.

If the hype-wagon is swerving across lanes because of control software bugs, you definitely want the person in it to be able to hit an E-stop button so that it stops swerving after a finite number of lanes.

How is it any more dangerous than brakes on a traditional car?

Anyone can slam the brakes in the middle of a highway.

I'm assuming the e-stop button would not be right next to the blinker.

It's only dangerous to the people behind you if they are following you and each other far too closely. Also, the vast majority of multi-car pileups in the US kill zero people. In the record-breaking 168-car pileup two years ago in Louisiana, only 7 people died, an average of 0.04 deaths per vehicle: https://edition.cnn.com/2023/10/23/us/louisiana-fog-i55-cras...

Also, as multiple people have pointed out, all non-self-driving cars already have this feature; it's called a brake pedal. Providing it should not be controversial.

Sorry, I'm afraid I can't do that, Dave, you're drunk.

> Also passenger might be inebriated and randomly push the button.

Modern societies are reasonably able to cope with potential misuse of publicly-accessible emergency equipment. Buildings have fire alarms. Airplanes have emergency exits with self-deploying slides. Trains have emergency brakes passengers can activate.

Misusing any of these can create a danger to others and is sure to be very disruptive. People do on occasion, and face punishment for their actions.

I didn't get arrested or fined, to be clear. I just got told not to do it again in a very stern voice.

That seems about right for a child doing that; an adult would probably be fined and kicked off the train.

Embarrassing as it is to admit this, I was technically an adult. In my defense, I thought it was an emergency. I was wrong. They didn't even kick me off the train. We were back on our way a couple of minutes later.

You could always tug the steering wheel. That's supposed to stop it.

"...Additionally, you may not sit in the driver’s seat, touch the steering wheel, pedals, or driving controls.

Violating these rules will impact your account standing and may lead to permanent revocation of ride privileges..."

https://support.google.com/waymo/answer/15486190

"Well, I got in a wreck and had 3rd degree burns, but at least my account is in good standing!" (Yes I know it's a totally different scenario to the article's)

Yeah, safety regulators would also need to prosecute companies that discourage people from using the E-stop button with terms like those.

How would a malfunctioning AI decide it's safe to stop?

It wouldn't decide whether it's safe to stop. A separate E-stop processor would have a preprogrammed stop routine that stops the vehicle as fast as it can stop safely, which is to say, without skidding and without making rear-end collisions inevitable if you're on the freeway.

> and without making rear-end collisions inevitable if you're on the freeway.

That means it has to decide whether it's safe to stop.

Stopping safely is no less complicated than the self-driving software in general. Sure you can have backup driver software, but it's just going to be the same software.

> but it's just going to be the same software

It does not have to be the same software. Its task is much simpler, and many situations where the normal software has to look for an optimal resolution can be handled by activating the hazard lights, stopping the car, and telling the passengers that the emergency stop is complete.

People talk a bunch of stuff about malfunctioning, bugged software and so on. We can assume, the car was just trapped in some infinite loop so it'll never reach it's goal for some reason but also wasn't able to realize that and call the routine for that. Fine.

It's not a dangerous situation for the passenger but it definitely something that makes you feel very uncomfortable which could lead to panic because you're trapped. The doors are locked and even if they weren't you cannot simply exit the car. That's okay. Trains don't allow this either to open the doors on a track section. You need a supervisor to do that. In case of an emergency you can still unlock the doors mechanically. So after pulling the emergency brake you can still do that. It would be interesting how these cars behave in case of a fire inside or something which leads me to my final thought:

In case of issues on or with a ride in a theme park, there are usually operators. So in case of a technical malfunction there's an emergency stop which should make disarm systems in a safe manner and bring the ride into a safe position or at least make sure it stops safely. Of course it's not possible to trigger an e-stop as passenger but an operator can do that in case you can somehow make clear that it's needed right now.

The situation in the video is a very bad experience because a phone call from the passengers device is needed and he was asked to do something in the app. Probably to identify the car and enable the remote control. Elevators handle this much better. There's an emergency system in the cabin which transmits all important information to the service center, so it's immediately clear where the emergency call originated from. An app on a smartphone should never replace this installation!

It happened not to be a dangerous situation for this passenger, but that is not always the case. See https://news.ycombinator.com/item?id=42646148 for a list of examples.

When I pulled the emergency stop cord on the train, I also pulled the emergency door opening lever. The doors opened, on a track section. I've used an emergency door opening lever more recently when the train had already stopped and we were being instructed to exit because of a mechanical problem (possibly a fire), but that was at a station.

Elevators, in my experience, also universally have E-stop buttons or switches.

Add a couple of pedestrians to that parking lot, as in a mall, and that situation turns dangerous quickly.

No, it doesn't. It just needs to brake slightly less hard than the antilock braking system is capable of. There is no complexity there. The only complexity is in ensuring that the E-stop processor can reliably override the rest of the car's control systems.

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