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Studies find automatic braking can cut crashes over 40%

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

#91

Post by vel0city »

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…

> One car length is way more than 15 feet to my mind, probably 40 feet or more

Cars in your area are on average 40 feet long?

A car length is about the length of an average car.

Either way, with a 40 foot "car length", 1-2 car lengths is then ~80 feet. The above stopping distance chart puts a 40mph stopping distance with reaction time at almost 140 feet. know is doing a maneuver which could result in them braking suddenly such as turning into another field of traffic.

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

#92

Post by giantg2 »

branon wrote: post #72
giantg2 wrote: post #61

Earlier quoted context omitted.

"I'm only one car-length away and still going 40 MPH. Another half-second and they'll be gone," These numbers must be wrong, and are terribly unsafe. Just off the top of my head, that's like travelling 60fps for .5 seconds is 30 feet, which exceeds 1 car length, even for my truck.

Assuming that a "car length" is always equal to the length of a car is the unsafe bit. A car length is simply the minimum safe follow distance based on weather, traffic, and speed. To my mind it has almost nothing to do with the literal length of a car.

Please provide a source for that definition. I've never seen that used anywhere.

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

#93

Post by troydavis »

Consumer Reports has a good summary of active safety features, then a breakdown of which models include or offer each feature: https://www.consumerreports.org/car-safety/cars-with-advance...

The features most related to this article are: FCW, AEB, CAEB, HAEB, and PD. Note that some manufacturers have much better implementations than others, so after you settle on a few models, investigate how good their implementations actually are.

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

#94

Post by dsfyu404ed »

BeetleB wrote: post #57
dsfyu404ed wrote: post #18

Earlier quoted context omitted.

The rules for accident liability aren't as rigid and naive as you are implying. The rear ender having to pay is just the base case that is used in the absence of other facts. If you drive "in an asinine manner" (the definition of asinine is subject to discretion and negotiation between the relevant insurance companies) and manage to make the front of someone else's care meet the rear of yours in the process AND there…

It probably varies by state, but people I know who've rear ended someone else have said that no one is interested in how it happened . The cops didn't care, and the insurance didn't care. The rule is it's your responsibility to maintain a safe distance. So sure - the guy in front of you may have been extremely reckless, but no one involved is even going to want to hear that narrative.

>So sure - the guy in front of you may have been extremely reckless, but no one involved is even going to want to hear that narrative.

Nobody cares about talk. Everybody lies when they have financial motive to do so and everyone who deals with accidents professionally knows this. That said, insurance companies care deeply about hard to falsify (i.e. anything better than heresay) evidince that show that their customer was not the cause of the loss (dashcam video, surveillance footage, 3rd party witness statements, etc) because the profitability of their business depends in large part on claims payouts.

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

#95

Post by emptybits »

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…

> One car length is way more than 15 feet to my mind, probably 40 feet or more depending on speed.

A car length is, literally, the length of a car. It does not vary with speed.

Exception: https://en.wikipedia.org/wiki/Length_contraction (coming soon in a software update to a Tesla near you)

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

#96

Post by branon »

vel0city wrote: post #91
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…

> One car length is way more than 15 feet to my mind, probably 40 feet or more Cars in your area are on average 40 feet long? A car length is about the length of an average car. Either way, with a 40 foot "car length", 1-2 car lengths is then ~80 feet. The above stopping distance chart puts a 40mph stopping distance with reaction time at almost 140 feet. know is doing a maneuver which could result in them braking sud…

With the amount of semi-trucks in my area, actually yes, average length of vehicles you encounter on the road is probably close to that.

I just used the term "car length" with entirely too much room for interpretation and am now getting torn apart for it, my mistake. I swear I'm not tailgating people LOL

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

#97

Post by VBprogrammer »

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.

I've had the additive cruise control do some fairly hash braking in situations which didn't call for it. One I remember was when passing someone who had pulled into a layby (a rest area just off to the side of the road) and was stopping. Once you grow to expect it it's not really a problem, you just put your foot on the accelerator until you pass something which you know the car might not like.

I've also had it activate in normal driving due to someone else doing something dangerous. I'm pretty sure I was on top of those situations but I'm happy the system had my back even if I didn't need it.

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

#98

Post by branon »

emptybits wrote: post #95
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…

> One car length is way more than 15 feet to my mind, probably 40 feet or more depending on speed. A car length is, literally, the length of a car. It does not vary with speed. Exception: https://en.wikipedia.org/wiki/Length_contraction (coming soon in a software update to a Tesla near you)

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.

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

#99

Post by athorax »

proggy wrote: post #87

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…

Low hanging branches heading up to our house trigger ours when it is breezy out. Super annoying.

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

#100

Post by vel0city »

branon wrote: post #96
vel0city wrote: post #91

Earlier quoted context omitted.

> One car length is way more than 15 feet to my mind, probably 40 feet or more Cars in your area are on average 40 feet long? A car length is about the length of an average car. Either way, with a 40 foot "car length", 1-2 car lengths is then ~80 feet. The above stopping distance chart puts a 40mph stopping distance with reaction time at almost 140 feet. know is doing a maneuver which could result in them braking sud…

With the amount of semi-trucks in my area, actually yes, average length of vehicles you encounter on the road is probably close to that. I just used the term "car length" with entirely too much room for interpretation and am now getting torn apart for it, my mistake. I swear I'm not tailgating people LOL

> I swear I'm not tailgating people LOL

If you're going 40mph and approaching nearly stopped cars at Don't get me wrong, I've had my emergency braking trigger for similar circumstances of someone turning into a parking lot off a feeder of a highway. But I don't blame my equipment, I acknowledge I'm not a perfect driver. The car knew it could have been quite a challenge to stop in time and so it took action. The better action would have been for me to be going slower and approach that situation with less speed, not to just blame the car for being cautious and forcing realistic safety margins.

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