Studies find automatic braking can cut crashes over 40% • Hacker News Board

Re: Studies find automatic braking can cut crashes over 40%

#81

Post by tshaddox » Tue, Nov 15, 2022, 4:28 PM UTC

branon wrote: post #69

berberous wrote: post #49

Earlier quoted context omitted.

Have you ever looked up stopping distances? https://www.automotive-fleet.com/driver-care/239402/driver-c... I don’t know how accurate the above is, but it suggest that the stopping distance at 40mph is 5-9 car lengths, so I have to agree with the above poster that if you are routinely leaving one car length and your car system is freaking out, you are probably driving unsafely. Keep in my that statistically this coul…

One car length is way more than 15 feet to my mind, probably 40 feet or more depending on speed. See my other comments about how nuanced this entire dialog will inevitably be. Don't you think it's more reasonable to assume we have different definitions of a car length? Perhaps I've used the term in a grossly incorrect manner. "One car length" to me equals "one unit of minimum safe distance taking into account road co…

I think you are confused (either that or I am!). I’m pretty sure a car length is literally the length of a car, which for a Crosstrek is around 15 feet.

Given this confusion, it does seem like it explains the root of the disagreement here, but that said, I don’t think it’s unreasonable for people reading your comment to assume that when you said “car length” you meant the length of a car.

Re: Studies find automatic braking can cut crashes over 40%

#82

Post by mritun » Tue, Nov 15, 2022, 4:29 PM UTC

mikeyouse wrote: post #73

sublinear wrote: post #67

I have a 2017 Outback and there exists a cluster of switches on the dash for easily toggling all the EyeSight features. They actually recommend to disable the "pre-collision braking" feature before driving through an automated carwash. Apart from that situation, I also disable it when I'm facing highly congested traffic for the reasons indicated in the other comments. It's very easy to do. I don't understand why this…

It's more startling but dangerous, but also, disabled the Reverse Automatic Braking when pulling a trailer. If you try to back into a parking spot with it engaged, the car will freak TF out and make an awful noise as it jams on the brakes. Or so I've heard.

Again I have one on my 2017 Forester, and never turned its safety features including AEB off. All it does when reversing is beep because the sonar sensor is confused. It never behaved unpredictably.

(and yes the AEB did save me from backing into things at least twice in these years, so I know it works)

Re: Studies find automatic braking can cut crashes over 40%

#83

Post by alphabettsy » Tue, Nov 15, 2022, 4:29 PM UTC

Workaccount2 wrote: post #40

branon wrote: post #10

Oof, my experience with with auto-brake in a 2021 Subaru Crosstrek (anecdotal, sample size of one, all that good stuff) is much the opposite. It's too sensitive and tends to brake shockingly hard during fairly mundane maneuvers. When backing up near a wall/obstacle, the auto-brake seems to kick in when anything is closer than three or four feet away from the bumper. I use my mirrors and have an accurate impression of…

Funny story, My sister got annoyed with the auto-braking on her new Subaru and turned it off. Three days later she rear ended someone, smashing up the whole front of her car. This was the third time she had rear ended someone. She keeps it on now.

> This was the third time she had rear ended someone.

Pretty wild. Seems like license suspension or retraining should be required.

Re: Studies find automatic braking can cut crashes over 40%

#84

Post by brookst » Tue, Nov 15, 2022, 4:30 PM UTC

hardolaf wrote: post #71

brookst wrote: post #56

Earlier quoted context omitted.

And if someone is following you too closely, but the lane to your left is clear, so it is in your interest to absorb the slack from someone in front of you turning because you can swerve left if they do something unexpected? I don't think anyone would complain about these systems if they had all of the context and made good decisions. But it is a problem when either humans or automated systems stand on the brakes bas…

I've never had a false alarm from the system on my car. But then, I actually follow the recommended minimum following distances and generally drive safely.

Well, it is either your superior driving behaviors, your car manufacturer's superior implementation, or just the way statistics work that not everyone sees every bug.

My car auto-brakes at 5mph for parked cars that are backed into spaces, which I am sure reflects poorly on my driving in some way, if we're adopting the "bad things only happen to bad people" model.

Re: Studies find automatic braking can cut crashes over 40%

#85

Post by indymike » Tue, Nov 15, 2022, 4:30 PM UTC

branon wrote: post #53

DiggyJohnson wrote: post #45

Earlier quoted context omitted.

I’m not comfortable at all claiming that you’re a bad driver in general, like the GP proposes, and maybe I’m taking your unit of measurement too literally, but I don’t think 1-2 car lengths is a reasonable follow distance in almost any circumstances above 45mph, two lengths is kinda the minimum to not bother the person in front of you. Again, I’m making a very general statement, that might not apply to the situations…

This is an interesting point. The Subaru's adaptive cruise control system treats a "car length" as a fairly large unit of measurement. One car length seems to be the literal length of the vehicle, plus some reasonable amount of buffer on both ends. Probably twice as large as the vehicle itself. And the faster you're going, the larger a single car length becomes. Infinite nuance :P But in general, very good commentary…

The Subaru uses two seconds per tick mark on the adaptive cruise display, so the distance changes as you go faster. At slow speeds, it's roughly exact car lengths, and at 65MPH it's considerably further.

Re: Studies find automatic braking can cut crashes over 40%

#86

Post by VBprogrammer » Tue, Nov 15, 2022, 4:30 PM UTC

branon wrote: post #69

berberous wrote: post #49

Earlier quoted context omitted.

Have you ever looked up stopping distances? https://www.automotive-fleet.com/driver-care/239402/driver-c... I don’t know how accurate the above is, but it suggest that the stopping distance at 40mph is 5-9 car lengths, so I have to agree with the above poster that if you are routinely leaving one car length and your car system is freaking out, you are probably driving unsafely. Keep in my that statistically this coul…

One car length is way more than 15 feet to my mind, probably 40 feet or more depending on speed. See my other comments about how nuanced this entire dialog will inevitably be. Don't you think it's more reasonable to assume we have different definitions of a car length? Perhaps I've used the term in a grossly incorrect manner. "One car length" to me equals "one unit of minimum safe distance taking into account road co…

You could just admit that you used the wrong term? One car length = the length of a car.

Re: Studies find automatic braking can cut crashes over 40%

#87

Post by proggy » Tue, Nov 15, 2022, 4:31 PM UTC

Implementation matters. The automatic braking on my compact SUV has falsely triggered hundreds of times over the course of 3 years, usually when transitioning from a moderately-pitched-down driveway into a roadway. The result of this scenario is the car coming to a dead stop with its front end halfway into a traffic lane, putting me and my passengers at greater risk of a collision from oncoming traffic approaching from the left hand side. It’s happened so often I’ve made a habit of disabling it whenever I exit certain commonly used driveways know to trigger the behavior.

Re: Studies find automatic braking can cut crashes over 40%

#88

Post by branon » Tue, Nov 15, 2022, 4:33 PM UTC

VBprogrammer wrote: post #86

branon wrote: post #69

Earlier quoted context omitted.

One car length is way more than 15 feet to my mind, probably 40 feet or more depending on speed. See my other comments about how nuanced this entire dialog will inevitably be. Don't you think it's more reasonable to assume we have different definitions of a car length? Perhaps I've used the term in a grossly incorrect manner. "One car length" to me equals "one unit of minimum safe distance taking into account road co…

You could just admit that you used the wrong term? One car length = the length of a car.

Sure, I'm fine with admitting that. It was an inevitable misunderstanding anyway because cars are different lengths so "car length" is largely meaningless.

The Subaru's adaptive cruise control system treats car lengths as variable units based on speed. It's much more liberal than I made it sound in the original comment. It sounded reasonable when I wrote it, but infinite nuance strikes again I suppose.

Re: Studies find automatic braking can cut crashes over 40%

#89

Post by lazide » Tue, Nov 15, 2022, 4:33 PM UTC

grog454 wrote: post #54

bhouston wrote: post #2

It feels like a simple thing but I also suspect it is effective from my personal experience. We have automatic braking (fixed: breaking) on my Toyota Rav4: https://www.youtube.com/watch?v=gbnoFbb8G8Q It is a simple thing but the PCS has been triggered 4 times in the last 5 years and never incorrectly. I think I would have stopped soon enough without it (as I've never hit anything in my 20+ years of driving), but it w…

> You shouldn't need it if everything else goes perfectly, but it doesn't hurt to have it. That's not how I see it. Computers react faster than humans even setting aside the mechanical delay of lifting your foot, moving it, and pressing it down again. It's more like running a linter on your code. 99.99% of the time it isn't necessary and you already knew what it was going to say, but the one time it does catch someth…

There is very little reason to be in a state where the advantage is the difference between a collision and not, is I think what they were referring to.

Adequate following distance, conservative driving, etc.

Not like that happens on freeways in any city, of course, but the point is - it shouldn’t matter, but should be nice to have.

Unfortunately, I’ve had numerous false triggers (highway construction barriers coming in rapidly from the side, while other traffic merged in), which made me disable mine. It’s almost caused several accidents in the last few years.

Re: Studies find automatic braking can cut crashes over 40%

#90

Post by sublinear » Tue, Nov 15, 2022, 4:34 PM UTC

mritun wrote: post #74

sublinear wrote: post #67

I have a 2017 Outback and there exists a cluster of switches on the dash for easily toggling all the EyeSight features. They actually recommend to disable the "pre-collision braking" feature before driving through an automated carwash. Apart from that situation, I also disable it when I'm facing highly congested traffic for the reasons indicated in the other comments. It's very easy to do. I don't understand why this…

I drive a 2017 Forester and in 5 years of driving it I never had to turn off any of its safety features including pre-collision braking.

I think, quite literally, one's mileage may vary. Not all stop-and-go traffic is the same.

It's not always safe to keep the huge distances apart at the speeds the system wants (other drivers will cut in). The system can also have a difficult time with motorcycles lane-splitting.

Anyway the way I see this is the switches are there for the driver to use at their discretion. I would hate for the industry to move towards full automation. I love the system as it works right now. Just my two cents.