Is the Emergency Stop Button More Danger Than it's Worth?

"Berang" (berang) 02/24/2016 at 22:15 • Filed to: emergency brakes

6

15

A drunk person, who is not fit to operate an escalator, might push the button and endanger everybody.

It may be safer to risk the occasional mangled human limb, or !!!error: Indecipherable SUB-paragraph formatting!!! , than risk a drunk person stopping a machine that can do its job just fine on its own, thank you very much.

No no no - wait - that would be crazy talk. Of course an escalator needs an emergency stop button. Even if drunk people might press it.

However Chris Urmson of Google thinks that letting humans override machines is “crazy”:

“...[if] we put an extra steering wheel or brake pedal there for the passenger to grab ahold of anytime. It would just be crazy to think about doing that...

...I think the idea that you want the person to jump in who hasn’t been paying attention or maybe had a couple of drinks with dinner and then jump in to override is probably not the right idea.”

But here’s a worry about autonomous vehicles: There’s a distinct potential that one could be hijacked, by hackers, for say, the purpose of kidnapping. Would it not be wise to have some sort of emergency brake or cut-off installed? Or do we just expect a passenger to leap from a moving vehicle if they realize it is not going where they expected it to go?

We’ve seen numerous !!!error: Indecipherable SUB-paragraph formatting!!! of cars being “ !!!error: Indecipherable SUB-paragraph formatting!!! ” in various ways recently, so it’s not as though the danger is implausible.

There may also be instances where another occupant is threatening or endangering other passengers - there should obviously be a way for a passenger to stop the vehicle immediately in such situations.

Or suppose a more simple problem, the primary brake system fails - the vehicle should have a back-up, which should be able to be operated by occupants. Cars have hand brakes too - and they’re not constantly being jammed on by drunk backseat occupants.

Whatever danger is posed by emergency brakes, is minimal, if not completely negligible. And even if the technology developed to the point where they were completely unnecessary, the mere existence of the control would be important to securing the confidence of users.

My problem with Melissa Walker’s article is not the reporting of things other people are saying - it’s the lack of questioning what they’re saying. Even if the questions seem dumb or basic at the time. Just taking the word of somebody who has a vested interest in a product isn’t really doing a service for readers.

My citroen won't start > Berang 02/24/2016 at 22:22

0

I have never seen a visible emergency stop button for an escalator.

DrJohannVegas > Berang 02/24/2016 at 22:24

1

I get where you’re coming from with the idea of drunkies hitting e-stops on escalators. (I’ve seen mostly sober kids in malls in NJ do it.) But, this is an instance of a fail-safe situation. (Where “fail” is an operator-determined state.) If the escalator stops moving, nobody is placed in greater danger.

Where I don’t understand the freak out is that cars today have limited redundancy in many systems. Sure, you have dual-circuit brakes and a handbrake (although it’s not really the same, as the braking force requirements by law are much lower for handbrakes), but beyond that, cars are not necessarily fail-safe.

Many engineering prototypes used on testing sites (and the open road) have e-stop buttons. Autonomous trams/monorails have e-stop buttons. But, for a car on a road, I am not sure whether an emergency stop is necessarily a fail-safe option in a car. If the autonomous car is designed to use existing infrastructure, which allows a lot of freedom in terms of pathing, I have a harder time imagining what a true fail-safe emergency stop looks like.

That said, I think that figuring that out should be an absolute requirement before all controls (aside from an e-stop, which should remain) are removed from autonomous cars.

On your last point: Hear, hear.

Berang > My citroen won't start 02/24/2016 at 22:24

0

That’s because they’re usually in an inconspicuous location, often here:

Berang > DrJohannVegas 02/24/2016 at 22:30

0

Think about the railcar as an example. There’s a built in failsafe in the braking system, if the cars uncouple or the brake hose ruptures, the brakes come on automatically. But there’s also an emergency pull cord or handle, button, whatever, that can be activated by a passenger.

If there is a danger that the operator, or the machine itself cannot sense, for example, a fire or a homicidal maniac attacking passengers - passengers can stop the vehicle. I can see similar emergencies happening in autonomous vehicles. So there’s an obvious need for at least some sort of overide, at the very least a brake or cut off for safety’s sake.

In fact the emergency brake cords were initially adopted because of fears of murders and muggings. There were a number of very famous cases in the 19th century of people being murdered on moving trains, while traveling in private compartments.

DrJohannVegas > Berang 02/24/2016 at 22:35

1

Yep. (Airbrakes on heavy trucks work the same way, too.) But, my broader point was that slamming on the brakes is ok on a railcar, as its path is determined and usually cars are spaced at some distance. Slamming on brakes on a road is not generally a good plan. Then you get situations like this (apologies for language/noise):

This may be resolved if autonomous cars talk to each other constantly, but that’s just another potential point of failure.

Berang > DrJohannVegas 02/24/2016 at 22:42

0

This assumes that the car would just stop in its tracks. there’s no reason that a self driving car couldn’t be designed to pull over whenever somebody activates the emergency brake.

I’m just thinking of situations, particularly amongst shared vehicles which in theory would be replacing buses and taxis and carpools. You might pick up somebody, who is threatening or dangerous to other riders. You’d hope there’d be a button to say “I need to get off right now!”.

DrJohannVegas > Berang 02/24/2016 at 22:46

0

Oh yea, I’m with you there. But, until the code for “make a smooth, safe, urgent stop” is figured out (and I am sure that it’s not that hard, given all the other barriers to making autonomous cars work), I’d just as soon not have a “stop right now” button be the only control. That said, I’m not entirely sure the “I need to get off right now!” button really is the same as an emergency stop button, if it’s doing a lot of other things, like planning a path to the shoulder/curb.

This has all been a long-winded way of saying: There’s a lot still to be hammered out on semi- or fully-autonomous vehicles, and anyone proclaiming to have the perfect answer should be regarded with deep suspicion.

Edit: To me, your urgent stop button sounds more like the pull cord on a bus, which has many of the same constraints/freedoms as a car. (But it’s the bus driver and not a malevolent computer which chooses to ignore it and blow past your stop.)

Berang > DrJohannVegas 02/24/2016 at 22:49

1

I think most people would be able to handle a plain stop button, but if the car is already self driving there’s no reason it shouldn’t pull over too. Unless of course that system has been hacked by some sort of mastermind. There would still be a need for some sort of master cut-off. The basic problem is there ultimately has to be some way for a person to have complete control over the vehicle, even if that control just amounts to turning it off or making it stop moving.

DrJohannVegas > Berang 02/24/2016 at 22:55

0

I get where you’re coming from, and I think we’re nearly on the same page. It might be worthwhile to look at the way human-robot interactions work in modern factories for insights. Since some operations are dangerous or difficult to stop mid-cycle, all of the safety comes from a positive control check to ensuring a cycle is not initiated until the operator is completely sure that everything is clear. In other words, combine a “are you really sure?” prompt before the door closes with a more discrete “absolute emergency” stop kind of control.

Berang > DrJohannVegas 02/24/2016 at 23:03

0

Well if you read the articles, the language used is about eliminating “human-oriented controls” under the rather dubious logic that if people crash vehicles when they have all the control, then eliminating all of the controls will stop crashes. I’d think having a brake lever or pedal wouldn’t pose any real danger, since usually, it’s not the brake pedal or the parking brake that causes accidents. And obviously the presence of these human-oriented controls has real benefits as concerns passenger safety.

thebigbossyboss > Berang 02/24/2016 at 23:07

0

That is dubious logic. Especially here in Canada. A moose does whatever the fuck it wants. Even an antonymous car can not stop instantly if all of the sudden a moose appears. Physics!

DrJohannVegas > Berang 02/24/2016 at 23:08

0

Ah. I’d wager that, given Urmson’s background, that statement was streamlined (read: had content removed) to simplify the message for a general audience. Most folks aren’t thinking about emergency stop buttons when they think of controls, especially when described as “human-oriented controls”. Basically, auto/mechanical enthusiasts (read: Oppo/FP folks) are not the target audience for that particular statement.

Berang > DrJohannVegas 02/24/2016 at 23:17

0

Interestingly, if you listen to the interview on NPR he is asked a question about what if a passenger wants to go faster (example: the vehicle is going the speed limit, but the rest of traffic is going faster) and he states that they did install a button that allowed a passenger to speed up the car - but that he also thinks this is a bad idea.

I wish he had been asked about emergency stops, but his general idea really is that occupants shouldn’t have control over the vehicle.

DrJohannVegas > Berang 02/24/2016 at 23:19

0

Yea, will have to look up the interview. Normally I am tuned in (ugh, what a shit pun) to NPR stuff, but must have missed it.

Svart Smart, traded in his Smart > Berang 02/25/2016 at 01:48

0

I think there should be an emergency stop, but maybe not one that’s accessible to every occupant of the vehicle. I was just thinking of the emergency exit row of an airplane. People seated in that row have to meet certain physical and mental requirements, and they take on extra responsibility in an emergency. People not meeting the requirements can still fly, just not in the emergency exit row. Similarly, there should be one vehicle occupant with the responsibility to use the emergency stop. (In a normal car, this person would be driving, but in an autonomous car, the role is completely minimized.) In other words, maybe an autonomous car still needs one sane, sober, cogent adult to keep an eye on things.

(Which reminds me of the joke about autonomous flight. There will be two occupants in every cockpit: The pilot, who feeds the dog; and the dog, who bites the pilot’s hand if he tries to touch anything.)