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Tesla Autopilot 'Predicts' Accident Before It Happens (engadget.com)
A dash cam footage suggests a Tesla on Autopilot may have predicted a nearby freeway crash before it actually happened. A video showed that a Tesla car driving on a highway in the Netherlands started to beep a few seconds ahead of two cars colliding with each other in front of it. A Tesla representative confirmed to media that the beeping heard in the video is indeed the sound of Autopilot's Forward Collision Warning. Elon Musk tweeted a news article about the incident, adding more credibility to the matter. From a report on Engadget:Tesla's Autopilot 8.0 has a particularly clever feature: it uses radar to track road activity two cars ahead, helping it avoid danger that you wouldn't normally see. And it now appears that this tech just averted a disaster. Dutch Model X owner Frank van Hoesel has dashcam footage showing his electric crossover reacting to a bad highway crash before it even starts. As you can hear in the video, the Model X's Forward Collision Warning system starts braking when it detects the SUV two vehicles ahead coming to an abrupt stop, even though the driver of the car directly behind it is unaware. The result? Van Hoesel's EV remained untouched when it could easily have contributed to a pile-up.
"predict - say or estimate that (a specified thing) will happen in the future or will be a consequence of something."
"Predict" is exactly what it did. "Predict" doesn't mean the mystical fortune-telling you seem to think it means.
"National Security is the chief cause of national insecurity." - Celine's First Law
There is such a thing as predictive modeling. Maybe the word "predict" bothers you somehow, yet the computer may have understood there was likely to be a crash before it happened. Maybe it only understood that it was a good time to brake. Giving probability to a future possibility sounds like prediction to me.
Reality is a slackware box running on a 386 tucked away in god's sock drawer.
Yes, it did predict trouble. It did not necessarily predict that the second car would hit the first (the accident that happened), but it predicted that it would hit the second car either way if it did not react, so it reacted to that prediction and protected itself.
So we live in an age where the only acceptable stories that can be reported in the media are negative ones?
No, this is a Tesla driver in the Netherlands, who made a dashcam video.
But - but - but - Elon Musk tweeted a news article about the incident, adding more credibility to the matter!
Sheesh, evil *and* a jerk. -- Jade
It predicted that *it* would crash if it didn't slow down. It didn't predict jack about the collision between the other cars.
Sheesh, evil *and* a jerk. -- Jade
next i want to hear the alert for missile lock and see it auto deploy counter measures..
It did literally "predict" the accident, just like I can "predict" that my pen will hit the floor should I drop it. It responded to inputs and reacted. In this case, it responded to inputs, drew a conclusion, and responded in a fashion that a human would have likely missed. There's definitely something there.
Still, I think an equally appropriate title would be "Tesla Autopilot avoids getting into an accident." Every action the autopilot takes (or even actions taken by human drivers) are based on predictions - Most of them obvious.
He's getting rather old, but he's a good mouse.
Would a person notice and react in the same way? If they are even semi-competent to be driving, yes. If they belong to either the 'stare directly at the car in front of you at all times' or 'my phone is so much more important than driving' camps, then no.
Did Tesla also report any/all instances where the forward collision warning sounded, regardless of whether or not a crash subsequently occurred? Otherwise this is just PR.
First off, an erratic driver is obviously worth paying attention to, so it's worth having the beep for near-crashes as well.
Also, in terms of the warning system's efficacy effects this probably isn't relevant unless it beeps so much as to cause drivers to ignore it. The false positive rate could be 75% and it still probably wouldn't beep more than once a week at the most (depending on where you live / Boston joke goes here.)
Wake me up when my Tesla can predict tonight's Lotto numbers.
You are welcome on my lawn.
would be for the small car in front to be piloted by a non-human.
You're correct, of course, that there was no mystical prognostication powers at work here. But in the same way we can predict a spacecraft's flight through our solar system based on a known starting state, so too can we say Telsa "predicted" the accident when it was apparent that the laws of physics were in control instead of the drivers.
Prediction doesn't necessarily imply the existence of magic. After all, meteorologists predict (although they prefer "forecast") future weather a week from the current date with rather uncanny accuracy. And climate scientists are also predicting that average global temperatures will rise over the next few decades, based on past data and predictive models.
Irony: Agile development has too much intertia to be abandoned now.
Did Tesla also report any/all instances where the forward collision warning sounded, regardless of whether or not a crash subsequently occurred? Otherwise this is just PR.
Tesla never reported any instances where the forward collision warning sounded. It's hard for it to be PR when it's not Tesla doing the reporting.
Anons need not reply. Questions end with a question mark.
By the time it "predicted", the accident sequence was already well under way, starting with the sudden deceleration of the larger vehicle. A 100% probability of loss-of-separation is an easy enough "prediction" so as to be called a calculation.
So we live in an age where the only acceptable stories that can be reported in the media are negative ones?
No, that's not true at all....
It doesn't matter if it's positive or negative.
It can see the cars ahead and it saw the SUV breaking so it reacted. It did not predict anything other than a vehicle in front is breaking and it started breaking faster than a human can react.
Tomorrow on slashdot..... "Scientists perform witchcraft by telling us that we will have a solar eclipse this next summer, and your jaw will drop and be speechless with a blown mind"
Do not look at laser with remaining good eye.
Gee, the comments on this so far stink. People seem to be prejudiced.
First, the dashcam video presented is not from Tesla, it's from an independent car fan who seems to have gotten it from the driver. It was then retweeted by Elon Musk.
The activity demonstrated is the Tesla Autopilot triggering on sudden deceleration of the second car ahead, which is not clearly visible from the dashcam view (and presumably equally not clearly visible to the driver). It appears that autopilot warns and brakes.
Autopilot does not predict what happens to the cars ahead (although in second-car detections it's probably implied) and "anticipate" would be a better word anyway. Autopilot anticipates that the Tesla will hit something if it doesn't brake.
Soneone on twitter pointed out that he heard the "disengage" sound after the warning sound, indicating that the driver brakes. I don't hear if, but I don't know what it sounds like. Does anyone else hear it?
Someone pointed out that the Joshua Brown accident might not have happened if the radar had worked then. Yes, it might not have. One should also point out that Brown was speeding and apparently not looking. Despite its name, "autopilot" is not ready for the driver to disengage.
Bruce Perens.
Hah, beat me to it. And you did it more amusingly; well done.
After the semicolon, you begin to explain (at a high level, without much detail) how it made the prediction.
And by teaching people how to predict things (observe a system's current state and extrapolate where it's going) you are helping to teach people that computers are not magic. Good for you. I didn't even know that anyone was trying to present it as magical. If I wanted to do that, I would have said Tesla divined the collision, using its Crystal Processor (a 1mm diameter crystal ball inside a chip, or something like that).
"Believe me!" -- Donald Trump
You mean the ones that had the advantage of having both cars in view, instead of a blocked view like the Tesla (driver) had. Ah, those cars.
Bert
I agree that the Hyperloop is cynical B.S. that Musk meant to deter the California high-speed rail project, and the semi-annual tunnel tweet is just naive. But he's doing pretty well with rockets. F9 first stage landing is a real coup.
Bruce Perens.
Exactly, the Tesla wasn't rear ended. Either was an other Tesla behind it or a mere human that did the same as the Tesla infront of it or the human kept an acceptable distance instead of tailgating.
This requires some basic independent critical thinking
Wow, talk about a real "physician heal thyself moment".
really isn't all that fast (only 2x Maglev),
A 2x speed improvement is a huge deal for any traveller.
won't be cheap (a jet engine, linear motor AND an airtight tube instead of a track? And how many ticket-paying people can cram into these cars vs. traditional rail?)
It may not be cheap but it uses a lot less energy per trip, and requires less maintenance, AND has dramatically safer failure mode (i.e. no multi-thousand foot drop), has no steering components to wear out/break, so over the long run it's probably as economical as a jet.
Traditional rail is as you said at least 2x slower...
cannot possibly be safer than or more convenient than air travel
1) If the tube is buried it's pretty damn safe from attack, even if elevated it would be hard to damage. But even if someone managed it would just stop the trip, it wouldn't kill anyone. Or maybe someone could get inside and kill some people but it's not like they could redirect the tube to a national monument or busy office building!
As for convenient, since there's no danger of the tube being aimed at anything but the end, there's zero need for anything more than standard bus terminal security, maybe an armed officer on board just in case though frankly I'd just let the passengers know safety was up to them, and let them carry,.
Just the fact you don't have to go through security means an automatic two-hour total reduction in travel time before you factor in actual trip duration. That's a pretty huge deal on any journey that's within two hours by air...
No a hyper loop doesn't make sense everywhere but something like the LA->SF corridor, or better yet baltimore/VA to DC.... it makes way more sense than a train because of the huge speed improvement. If you have dual tubes you could have really impressive throughput.
I'm no Musk groupee, I think he's fine but not any kind of genius. But the Hyperloop is an idea that makes a ton of sense because of the large spread of benefits it offers.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Did he tweet it before the event?
Yes, SpaceX is doing alright. But he's still talking nonsense about establishing a colony on Mars as well, isn't he?
There are fantastic-seeming things that are plausible in our lifetimes. Like, say, general AI or the scaling up of countless nanotech technologies that are still in their infancy. It's a waste of street cred for him to talk about this stuff. It's not that I fear his failure; it's that I fear young geeks becoming disillusioned when they realize his failures were mostly due to him being full of crap. Why can't we give young people at least semi-realistic dreams?
If we wanted a Mars colony then it's all about biotech or maybe (if someone can invent some nanites) nanotech. The rocket to get us there should be at the bottom of our priority list.
Exactly, the Tesla wasn't rear ended. Either was an other Tesla behind it or a mere human that did the same as the Tesla infront of it or the human kept an acceptable distance instead of tailgating.
Or the Tesla autopilot gauged the distance to the trailing car and moderated its braking to ensure that the human behind had sufficient time to slow. That's exactly what I'd do in that position; any experienced heavy-traffic freeway driver knows that the first thing you do when you start braking to avoid something in front of you is check the rearview mirror so you can adjust your braking appropriately to avoid getting yourself rear-ended -- or to decide if you need to swerve into the emergency lane. Of course, the autopilot system has the advantage that it already knows the position and speed of the vehicle behind, because it looks in all directions at once.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
Of course it didn't predict the actual accident, but it did see the car two cars ahead abruptly slowing down (by bouncing the radar signal underneath the car in front) and reacted by braking in time. The car directly in front of the Tesla never even touched the brakes.
That's pretty impressive, and the model S and X are the only cars with that capability.
The notion of prediction is not applicable to a partially observable, stochastic environment.
I would ask if you used a software, but instead I'll just turn off a hardware and go read a literature. *sigh*
If they are even semi-competent to be driving, yes. If they belong to either the 'stare directly at the car in front of you at all times' or 'my phone is so much more important than driving' camps, then no
So IOW, it's superior to the average driver? Counties with decent driver's ed might well mock, but others ought to consider adopting the tech en masse today.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The car directly in front did not even touch the brakes. It was a very sudden and unexpected deceleration two cars ahead.
Sure, I try to keep track of multiple cars in front, driving at the far left of the left lane so I can see any brake lights come on ahead, but sometimes you just can't (behind a large van, for example) and noticing such a sudden stop while the car directly in front of you keeps going... no, most people would just have crashed into it. Hell, most people can't even stop in time if the car directly in front suddenly brakes, let alone the car in front of that car.
The car behind the Tesla could see the Tesla's brake lights. The car in front of the Tesla never braked.
It did literally "predict" the accident, just like I can "predict" that my pen will hit the floor should I drop it.
This presumes that the "accident" is only the collision and not the entire stream of events. The stream of events was not predicted, just the outcome after initiating events created certainty, or near certainty of the outcome. It seems that the accident was detected and avoided rather than predicted in this sense
Or could similar conditions result in a prediction of a collision, but not result in one? Your laptop drop has certainty whereas the events leading up to the collision may have had uncertainty which could have allowed for a different conclusion.
The key questioss as to how impressive this technology is (and it sounds impressive and useful) is how early in the event stream can it accurately predict accidents, under how many different scenarios does it reliably work, and how many false predictions are encountered.
So does that mean it also "predicted" that it would kill that driver who slammed into a transport at high speed?
That was before the 8.0 update. Unlike other cars, Teslas get updates. The old software just used a single radar beam, which passed underneath the high trailer in the accident you are refering to. The new software lets the radar beam scan around to create a point cloud, tracking multiple objects. In an identical scenario, it would have seen the trailer and braked in time. And it can also look two cars ahead by bouncing the radar signal on the asphalt, which is what saved it in this latest video.
But - but - but - Elon Musk tweeted a news article about the incident, adding more credibility to the matter!
That behavior is predictable.
Musk picks terms to make things sound more impressive than they may actually be. I have seen accidents about to happen and avoided them many times in my many years driving, as I'm sure most of us have. In none of those cases did we go around saying we 'predicted' those accidents. We say we 'detected and avoided' them. That is exactly what this technology did. That should be impressive enough on its own, and its certainly useful, but its not as attention grabbing which is Elon's primary objective. You can argue over the term and say it is technically correct, but get real, its not how we ever describe such a thing in real life.
Except sometimes you're driving behind a large van and can't see anything ahead of it. The Tesla radar actually bounces its beam underneath the car in front of it.
Well it worked great that one time out of a few hundred.
Tesla rarely has customer dashcam videos for every time it "has" worked...we mostly only get to hear about the failures, which given the number of Teslas on the road that used autopilot in 2016, are considerably few.
...airbags and seatbelts have saved countless but we don't see an article praising how well it works.
You mean we don't see them anymore...there are literally thousands of articles and advertisements about airbags and seat belts going over the past 60 years.
Getting lots of mass there cheaply lets the other solutions be a lot less fancy, though.
Well, they do advertise it as bouncing underneath the car in front, so it should also work behind a van without a rear window.
They updated the radar software. Instead of using a single beam, it now scans around and tracks multiple objects. Uses a constantly updated database to avoid false alarms for street signs and such. Free over-the-air update for all autopilot Teslas. It would now see that truck and react accordingly.
You're right. This wasn't a "prediction". The car's radar is able to see two cars ahead and saw that traffic was stopped so it put the brakes on and alerted the driver. Impressive performance but not psychic.
I don't read your sig. Why are you reading mine?
That's SpaceX's *other* big myth, though: there's a pretty hard floor on how low the price can go on these things. Being good at shaving off some nickels and dimes here and there simply means you're competitive; it doesn't at all mean you're revolutionary. They're not (to my knowledge) building a space elevator or railgun launch system or something.
And not just for Tesla either. Interesting how the video is published through the Twitter account of a personal injury consultant, no? It's not linked from the Tweet that's mentioned in the article and news outlets are actually conversing with this guy for the rights, even though their involvement seems lateral at best. Look for the video online and you find the same dude posting the tweet wherever they will have it (instead of just posting the YouTube copy that's also available, of course https://www.youtube.com/watch?...
Also, is it really prediction, or is it just the Tesla noticing the car right in front of it suddenly breaking? Look at its break lights and course change (0:04 to 0:06).
Taking into account more of the available information, just not the car directly in front is just simply good driving whether it's a human or an AI vehicle. Happy to see this working in practice at least this time on a Tesla. One of the reason I hate riding with most drivers is that it seems very common to give driving only a minimal amount of attention and focus.
If the car in front of you hits a stationary car, you'll need to have left quite a lot of distance (well more than the recommended 2 seconds) to come to a stop in time. Nothing to do with tailgating, just physics. Recommended distances are based on reaction time, assuming the car in front is braking like you do. If it comes to an abrupt stop due to a collision, those two seconds are not going to save you.
So that's why good drivers try to look ahead (like I do), but sometimes you just can't. And the the Tesla radar can be a big help.
After watching that video, it's clear that "Autopilot" didn't predict anything. When the lead car suddenly stopped, it was obscured by the car in front of the Tesla. The Tesla detected the stopped car just before the second car collided with it, and warned the driver that they were approaching a stopped car too quickly.
Well, OBVIOUSLY the car that slammed into the stopped car missed that.
If I have been able to see further than others, it is because I bought a pair of binoculars.
it should also work behind a van...
...DOWN BY THE RIVER!!
This will save lives, full stop. You can crap all over Elon if you want, but the guy actually gets shit done. No it's not perfect, but it keeps getting better and it is at the point where it will save lives.
To be fair, the driver in that incident totally missed a GIANT FUCKING TRUCK crossing the road! Say what you like about humans doing this sort of thing easily all the time, but clearly some humans some of the time suck goat balls at it. Any technology that can assist even a little bit in these cases will save lives.
Human Rights, Article 12: Freedom from Interference with Privacy, Family, Home and Correspondence
Can we please get some scientifically literate moderators in here? This is getting absurd. He thinks that the closer you are to the site of the breech the worse off you'll be. This is a blatant violation of conservation of momentum. What the hell is acting on the in-rushing air to slow it down to protect something that is "about ten feet away"? The 1/1000th of an atmosphere that's supposed to be in there?
If there's something wrong with the assertion that the air will accelerate up the tube (not travel constantly), I will be suitably chastened but still curious to hear the explanation of where and how that gravitational kinetic energy is being transfered. (Air pressure is created by gravity.) Post AC if you've already modded.
I have seen accidents about to happen and avoided them many times in my many years driving, as I'm sure most of us have. In none of those cases did we go around saying we 'predicted' those accidents.
This may say more about your use of english language than anything else.
You saw something about to happen did you?
predict:
verb
say or estimate that (a specified thing) will happen in the future or will be a consequence of something.
English is a rich language. Why use a word like "detected" when you are describing an event that hasn't happened yet? If you're talking about traffic abnormalities then yes you "detected" it. If you're talking about the impending collision then you "predicted" it and then "avoided" it.
But my guess is you were more concerned with heaping shit on Musk / Tesla, which is a shame because all you showed is that his language skills are more impressive than yours may actually be.
Or maybe you completely missed my point, I never said the term was not technically correct, I even said you could argue it was. I bet you wouldn't use that term if you had just avoided an accident.
The Netherlands, where this accident happened, have very strict driver education laws. The exams are both theoretical and practical. Most people need about 40 hours of driving lessons to even qualify for the exam. A lot of people don't even get it on the first attempt and have to re-take the exam later.
Even then you still see a lot of folks driving around who should never have gotten their license, or should have returned it. Tesla's and other cars with this software should be a major improvement in road safety.
Therefore, by the (faulty) logic you're using, you're just a cow with a keyboard - osu-neko (2604)
Fun fact: a lot of accidents with moderate damage occur where the driver presses the brakes deeply, then releases because he or she realizes someone might be behind them, and THEN collides with the car in front. Mercedes specifically created an emergency brake system to counter this. It would keep applying the brakes when pressed "vigorously" for a few seconds after the driver released them. Gives you a hell of a surprise the first time you feel it...
Therefore, by the (faulty) logic you're using, you're just a cow with a keyboard - osu-neko (2604)
Fun fact: a lot of accidents with moderate damage occur where the driver presses the brakes deeply, then releases because he or she realizes someone might be behind them, and THEN collides with the car in front. Mercedes specifically created an emergency brake system to counter this. It would keep applying the brakes when pressed "vigorously" for a few seconds after the driver released them. Gives you a hell of a surprise the first time you feel it...
Ouch. That seems like a cure worse than the disease.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
If the driver behind the Tesla was any good, they were looking well beyond the collision and reacted before seeing any brake lights on the Tesla.
Slams on brakes. Car behind rear ends. Real prediction, and correct.
[Get Smart, with a psychic that KAOS wants to kidnap.]
Musk picks terms to make things sound more impressive than they may actually be. I have seen accidents about to happen and avoided them many times in my many years driving, as I'm sure most of us have. In none of those cases did we go around saying we 'predicted' those accidents. We say we 'detected and avoided' them. .
Yes but it detected the braking of the car ahead of the car in front, which didn't seem to brake at all until the crash. From the video the braking car was barely visible. That's pretty impressive.
How's life in the hypocrite lane?
The car merely noticed a speed difference with the car in front and started to brake. As the distance grew smaller and speed difference grew the braking became harder. Standard feature on that car.
You need to be raped by a wild boar and left to die, alone, in the woods.
Even with unlimited distance, you can't see past a big truck for the wave of red lights.
That has nothing to do with tailgating.
Because of reduced visibility, it makes sense to increase the following distance, but you still won't see past the truck, apparently a Tesla can.
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
If you watched the video, you'd know that it wouldn't have helped in this case. That the vehicle in front stopped is not visible until after the car between it and the Tesla crashed into it.
No, just the people who know physics. The experiment in video you have shown ignores basic physics: 1. Hyperloop doesn't need the tube to be tight around the train, so the air can travel around the train thus reducing pressure differential 2. Pressure grows squared, but the effect of mass is in third, so the air wouldn't even budge a train. Nothing to do with Musk, it simply seems that some people know physics :)
I bet you wouldn't use that term if you had just avoided an accident.
That depends entirely if I "predicted" the accident before it happened or simply "avoided" it once two cars hit themselves. That's how english works. We don't adjust the language to suit context. The language itself is clear.
There is a big difference between being a long way off from the incident or the next car behind it..
... It's real news!
The language itself is clear.
No, the english lanquage can convey different meanings with the same words, and choice of words in a particular context can convey different meanings or impressions. "predict" sounds a lot more impressive that "detect". If you saw two cars obviously about to collide and reacted accordingly, you would not go around telling people you predicted the accident.
Exactly. It calculated that the probability of the vehicle ahead making a sudden, unplanned stop exceeded the threshold at which it was programmed to take action.
recommended 2 seconds
At 25 miles per hour, maybe. It's at least 4 seconds at highway speed - reaction time is too critical. You can't only prepare for tailgating, you really need to assume that anyone ahead of you can crash at any moment.
Four seconds on the highway :-)))))
You don't drive much, do you?
Thanks. I'm really getting tired of the tech-billionaire-as-culture-hero mentality in the stories here.
Sheesh, evil *and* a jerk. -- Jade
Not even particularly impressive. The autopilot was allowing plenty of following distance, even a human could have reacted in that timeframe. I could see the back corner of the black SUV stop the same second in the video that the beeping started. I would have reacted in exactly the same way.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
And the car directly behind was not unaware- he attempted to evade, but didn't quite make it, which is why the rear-ending hit the corner of the SUV and the red car only had damage on the driver's side
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
Dumb luck causes Tesla's "autopilot" to look more ingenious than it actually is.
BeauHD. Worst editor since kdawson.
I live in the Boston area, and I had a vehicle with a similar radar system for emergency braking for about 6 months. It beeped at and/or braked for me maybe half a dozen times during that period (so about once a month), and about half of those were actually instances where I might have actually gotten into an accident without it (one would have certainly been an accident, or very close to it). So, it did a pretty good job, and wasn't providing false positives at a rate that would even approach annoying.
This ignores the fact that it is a *wall* of air with literally miles and miles (i.e. tons and tons) of air behind it. If the air isn't traveling at 600+MPH, it will be relatively incompressible. If it *is* traveling at 600+ MPH and the car traveling at around the same speed, it will be somewhat compressible but I suspect the deceleration forces would still be extreme.
/r/AskPhysics.
If you're interested in an actual answer here (as opposed to mere smugness or hero worship), I've just taken up the matter at
Don't waste this guys time with conspiracy theories. He doesn't fall for anything!
and choice of words in a particular context can convey different meanings or impressions
Welcome to my point.
"predict" sounds a lot more impressive that "detect".
Indeed because the act of predicting is more impressive than the act of detecting. Now if you want to take issue with the specifics of the instance and call Musk a liar then be my guest. But what you are claiming is that people don't use words like "predict" to describe accidents which either means they didn't "predict" them or they don't have a sufficient grasp of the English language to make their point correctly.
If you saw two cars obviously about to collide and reacted accordingly, you would not go around telling people you predicted the accident.
I would, because I'm not an idiot who dumbs down language to borderline newspeak for shits and giggles. I may describe the act of predicting by saying something like "I saw it coming" depending on how much alcohol I've had but to say I "detected" it would be wrong. The wrong word describing an action I didn't do.
The Tesla saw it with radar, by definition that requires line of site.
No, it does not. Bouncing under the car ahead is hardly 'line of sight'.
You can look over, under, around and even through the windows of some vehicles. Can you figure out which one happened here?
Under - as it was designed to do.
air can travel around the train thus reducing pressure differential
Not something you can hand wave away, by the way. You're talking about aerodynamic displacement around and behind the vehicle generated from forward momentum. We can't assume this displacement will just automatically happen at a fast enough rate to ensure that the vehicle doesn't fatally decelerate.
It's seeming as though things are a bit more complex than I initially thought, but that doesn't give you any points for your hand-waving dismissals. In particular, anyone who flatly says that the air wouldn't even budge the vehicle is full of shit.
But the other cars stopped far enough along that they would have been part of the accident, had they not been off to the side.
Ever had a van cut in front of you on the freeway? There's some time before I can establish a safe interval, speaking for myself.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Too much. Too many close calls because of stupid people.
Accurately maybe. Strictly? I'm strict about it to the point of practicing the martial art of antitrafic (when in a jam, slow down to 5mph below average speed, to build a space in front of you and avoid stop-and-go starts). I wish more people knew about it, there would be far fewer accidents and we'd all get where we need to go faster.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
If you look at Dog-Cow's comment, there is a Parent link at the bottom of it. This button will highlight the post to which he was replying, and let you know that this is the comment he believes caused the AC to diserve such wonderful treatment.
Because you have a brain the size of a pea.
Do you live in some backwater redneck county that doesn't provide basic science education?
Go put on your Tinfoil hat.
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?