111–120 of 177 posts
Got a new M340i a month ago, first day driving it I get cut off by some 90 year old in a buick who didn't want to miss his turn. Was really glad to have automatic braking, by the time my foot had lifted off the gas it was already braking.
I wonder how many extra crashes will something like this trigger and who will pay when accidents happen because the car decided to break for no apparent reason. I've seen PCS working well at slow speeds and, arguably, they would be more helpful at higher speeds. But would you trust such system with your life at high speed on a busy motorway ?
> who will pay The person hitting you from behind would be at fault anyway, at least where I live you are required to keep enough distance to stop even for no apparent reason, if driving in a lane and not moving to another. If you do it whilst moving in front of another car as it could be on you as you are required to yield and leave enough space to not hinder or endanger the driving of the other vehicle. This also i…
Where is this place where drivers just magically pay for damages? Where I live in the US, the person who hits you from behind is probably going to back up and just drive away.
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Sure, but saying this is meaningless when we're actually talking about follow distance. Cars are different lengths. To me, a car length should simply mean the minimum safe _length_ at which to follow the car in front of you.
This would lose all communicative benefits. Teaching a young inexperienced driver “just always keep one car length” where one = safe, is meaningless. I don’t know you, but I believe a majority of people underestimate safe stopping distance. That’s why the webpage I posted, which is one of many similar ones, exist. That’s also in part why there are so many accidents. People are also bad at estimating feet, so telling…
Not if taught correctly, which I think it's important to note that we can't really do via textual communication.
In the driver's seat, during a driver's education course, you might learn that a car length is the length of an average car, but you also learn how to count the seconds of stopping distance you have in front of you. In addition, you learn that weather, traffic, and other factors can affect stopping power/distance, the point being that the whole system is incredibly dynamic and variable.
One can't reduce a dynamic traffic situation down to "X car lengths = safe." Similarly, saying "1 car length = a safe distance" doesn't really help either.
The idea is to teach people what "safety" actually looks like. How it's referred to is secondary. The proof is in how badly I was misunderstood when I said 1-2 car lengths. I _know_ I'm keeping enough distance, because I know how to judge a safe traffic situation.
I don't really care what a car length is or isn't, it's fairly irrelevant because safety is a much bigger picture than units of measurement.
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Nobody's approaching nearly stopped cars, I think you have misunderstood some other facet of my post. I sometimes approach _decelerating_ vehicles, _while I am also decelerating_
> Nobody's approaching nearly stopped cars Yes they are, further up this comment chain is: > for example, if they're turning and will be gone in a second anyway That car turning is a nearly stopped car, doing a maneuver which could result in them stopping suddenly and unexpectedly. Going 40mph less than 80 feet away from that car turning is absolutely an extremely risky manuver. You don't know they're going to be gon…
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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.
Personally, I find it somewhat confusing, but people should probably be more aware that it's a thing and not necessarily someone mixing up terminology.
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 fr…
False positives usually happen when there are cars parked along a turn, but I ignore this completely.
Over the course of the five years I had this car it prevented a collision twice this way.
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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…
It's effectively impossible to maintain safe stopping distances in many places. Speaking from experience in Chicago, it's just a concept that doesn't exist for many people. And if you are driving slower in order to maintain a safe stopping distance, you're creating an extra hazard on the road by maintaining a larger speed differential from the rest of traffic. Not to mention, you increase your own risk of accidents b…
That incident gave pause. If the brakes had engaged, might that have caused a crash?
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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.
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That was just one example. I've clarified my original comment, previously I was using the term "car length" in a way that did not make sense to others. I should have said "seconds of follow distance" All of this is infinitely nuanced anyway. There might not be a side street. It can happen on the highway too when cars switch lanes to exit. And it's not like it happens every day, it's fairly rare, I just have yet to ac…
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…
I don't think it's reasonable to prepare for the car in front of you to stop in place as though it had hit a brick wall. Instead, the safe follow distance is derived from the current speed and breaking power of the vehicle I'm operating and the vehichle that's behind me, and the distance to the vehichle behind me.