[vaughanb]

Anti-lock brakes never yielded the accident reduction expected, primarily because drivers used the improved braking performance to drive faster in poorer conditions.

I guess the AEB works at reducing accidents because it IS autonomous and does not "improve performance".

BTW the KPI is reduction in insurance cost.

[SomewhatLikely]

On the other hand death rates have plummeted in recent decades thanks to all the safety advancements.

[fyfy18]

I wonder how many minor incidents it has prevented though. I was raised in the country where roads are often wet or icy in winter. Without ABS if you go around a corner and hit some black ice there is a good chance you would spin out and end up in a hedge or a tree. At the low speeds you need to drive (<20mph) it’s unlikely that the passengers would suffer any serious injuries.

[bowlich]

As someone who drives rather frequently in atrocious winter weather conditions. I often wonder how AEB will handle black-ice and deep snow where tapping the break gives you a chance for loosing traction and ending up in the ditch.

First rule of winter driving is don't touch the brake.

[KozmoNau7]

No, the first rule is "be smooth". No sudden sharp inputs, give the car time to settle and adjust to what you're doing.

You can absolutely brake, you just have to be smooth and gradual.

[jakobegger]

> First rule of winter driving is don't touch the brake

That doesn't sound right. Pretty much all cars today have ABS, which should make sure that you don't lose traction.

When I first drove a car with ABS in winter I was amazed how well the breaks worked in bad conditions -- of course the car would take a lot longer to come to a stop, but it did come to a stop.

[gargravarr]

The key feature of ABS is that it prevents the steering wheels from locking up, allowing the driver to steer around the obstacle. On loose surfaces, ABS can cause braking distances to increase; locked wheels can dig into gravel and slush, causing it to stack up and increase friction. ABS is also useless on sheet ice (but then, no braking system is genuinely at an advantage there).

These are edge cases though, and ABS does generally improve braking distances. At the very least, it gives you a much better chance of avoiding the obstacle in your path.

[KozmoNau7]

You really shouldn't have to brake hard enough that the ABS comes on. Be smooth, don't jam the pedal, brake right on the edge of ABS activation.

[dfee]

Having just escaped from the snowpocalypse of Minneapolis tonight, I can tell you this is right.

The other thing is to accelerate through turns - it helps maintain traction.

[zaarn]

I guess AEB will engage the brakes like a human would so the other safety systems like ABS and ESC so the car wouldn't behave worse than if a human would break.

Depending on the conditions that can be fairly acceptable, for purposes of drifting a modern car's breaks suck a lot thanks to those two (the handbrake is free game tho)

[clhodapp]

> drivers used the improved braking performance to drive faster in poorer conditions

That's not the ideal outcome but it's still a net win, no?

[gargravarr]

A German taxicab company did a study, pitting half its fleet with ABS against the other half without it. The accident rate stayed the same (in fact, was insignificantly higher) in the half with ABS because the drivers felt overconfident in the braking system:

https://web.archive.org/web/20100921074926/http://psyc.queen...

[clhodapp]

Yep! But they got to drive more aggressively without a substantial increased risk to their safety! Being able to go faster in the rain is useful in and of itself!

[xiphias]

The problem with this combination is that it may reduce the number of crashes/injuries, but increase the number of deaths at the same time

[AFNobody]

Faster = higher probability of an injurious and/or fatal accident.

So from a safety standpoint, that is a not a win.

[tialaramex]

A lesson from the ABS experience has influenced the design of AEB systems. The problem isn't so much that humans abuse the ABS to drive in harsh conditions as that they don't understand that they're relying on the ABS at all. They go around a bend too quickly and they don't think "Man, I nearly came off there, good thing ABS intervened to keep the car going where I point it" but instead "I'm great at this driving thing, a less skilled driver would come off there".

In AEB systems the emphasis is on dramatic interventions when calamity is imminent. So for example rather than gently brake pre-emptively because you seem to be getting a bit close, AEB is focused on braking very hard at the last moment, this doesn't feel like your skill saved you, it feels (correctly) as if the automated systems kicked in to avoid a crash.

[rstuart4133]

I'd agree anti-lock brakes haven't had much effect. It will only help people who haven't learnt how to brake properly, but we all get plenty of practice at that during everyday driving so I expect the difference is marginal. But the story is different with a related technology, ESP, which is mandatory where I live.

No so long ago I was caught out not paying enough attention approaching a roundabout at a creek crossing on a rainy day. It dawned what I hadn't allowed for the slippery road conditions on that day when the car started to slide towards the creek rather than go the direction I was steering. I'm by no means an expert driver, but I've spun a car off a dirt road into the bush a few times in my miss-spent youth, enough to know when I've lost control beyond recovery. I only had a few meters before a collision, but another thing I learnt during that miss-spent youth is if you can arrange to slide into a guard rail sideways so the load is spread along the entire side, if your speed is low enough you might get away with no panel beating at all. So I eased off the brakes to get maximum steerage.

Then the car noticed the steering wheels had lost traction, and the ESP cut in. ESP boils down to steering with the brakes and engine - sort of like a handbrake turn, but the brakes are applied to a front and a rear wheel on opposing sides and the engine powers the other two. There is no way to do it manually. Turns out it's amazingly effective, as it both slows you down and gets the car pointing in the right direction.

There was no accident that day.

I've stomped on the brakes quite a few times to see what ABS in action feels like. I reckon I can do a better job manually. But there is no way I'd drive so crazily that ESP cut in on anything but a skid pan. Besides, there is no point. I know I could never do as good a job, because as I said, there is no way to manually replicate what ESP does. Having said that, a good racing driver will do better without ESP because they get the car pointing in the right direction before it starts skidding - but that requires paying more attention than I was at the time.

[opencl]

I certainly hope that people do not get practice braking as hard as possible without locking up the wheels during everyday driving. Everyone 'learns' it when they first learn to drive but without frequent practice it is not going to be your immediate response when you get in a situation that requires sudden very hard braking to avoid a collision. Modern ABS is probably better at braking than 95%+ of people that aren't race car drivers ESPECIALLY in the situations where it's actually needed and people are probably panicking.

What you refer to as ESP is usually known as ESC where I live and it's also been mandatory here for a while, agreed that it is pretty incredible. I can definitely see it giving people a false sense of security especially in low traction conditions like snow/ice/rain.

[leoc]

Related to this, I wonder if insurers are going to demand access to an insured car’s autonomous-braking data?

[greglindahl]

Your airbag already records that info, if it fires.

[gruez]

don't worry, it's going to be siphoned off next time you get your car serviced anyways