But buyer beware. Even within the IIHS safety standards, there is considerable variability. I love my Toyota Corolla (2017), but it's braking will only take a few mph off after warning you. I can't wait until my lease expires and I can upgrade to the Subaru (edit: or maybe the Volvo from TFA). Look up the videos, they are fully capable of stopping without any collision up to ~40 mph (disclaimer: never rely on these safety features, it's still your responsibility to be safe).
Do your research, happy and safe driving!
I've learned the hard way not to expect anything from other drivers on the road.
Make sure your following distance is such that you have enough time to react to completely oblivious driving behaviour from other drivers.
While I fully endorse this ideal, the reality of driving in high-traffic cities is that it's impossible. Every time you adjust to leave proper space, someone will come along and appropriate your safety buffer. When you slow again to allow enough space, the pattern repeats.
As others discussed throughout this thread, there are many situations where drivers violate the safe following distance rules. Aside from the lack of attention scenarios, I think many drivers take calculated risks to temporarily reduce their following distances while performing some other maneuver. They should incorporate this new idea of neurotic automatic-braking systems into this risk calculus, so they don't get caught in a situation they cannot handle.
While we have a mixture of different vintage cars (and drivers!), I am afraid we will remain living in interesting times...
You also give yourself a buffer when vehicle ahead have an emergency stop - imagine there’s a truck behind you.
I guess what I’m saying is these ‘brake checks’ are welcome, even if they only serve to educate people.
There are three scenarios if I'm not overtaking:
1) I'm going faster than the vehicle in front. In this case, it doesn't matter if another vehicle pulls in between us because I'm about to overtake anyway.
2) I'm going slower than the vehicle in front. In this case, it doesn't matter if another vehicle pulls in between us because I'm falling back and the gap is ever-increasing.
3) I'm going approximately the same speed as the vehicle in front. In this case, there tend to be two ways a vehicle pulls inbetween us:
a- it's merging from an on-slip-road (on-ramp?), in which case this doesn't happen often, and I'll just fall back or overtake
b- it's just overtaken me, then slotted into a gap that's too small for it anyway. If the car has overtaken me, it's mostly because it wants to go faster (in which case it will probably vacate the space again soon) or it wants to pull off (in which case it will definitely vacate the space again).
If I am overtaking, then yes, someone may pull into the gap, but I'm still overtaking the vehicle I want to get past.
If you stop worrying about going 2mph faster than another lane of traffic, then leaving a safe gap is mostly pretty easy and stress-free. It will only take you 15 minutes longer to drive 200 miles at 65 than at 70.
c- a vehicle in the lane to your left that you were going to overtake has itself caught up with a slower vehicle and wants to pull out to overtake it, moving into the gap in front of you
d- a vehicle with an impatient driver is undertaking traffic (passing to the left of slower vehicles) and then moves into the gap in front of you.
The first of these is a normal situation, but still results in a vehicle moving into the space in front of you, sometimes without accelerating up to your speed first. Fortunately, it's usually easy to anticipate this situation, and many drivers will helpfully drop back a little to allow more space for the other vehicle to move out.
The second of these is a result of aggressive and probably illegal driving, and is more of a problem because the driver cutting in may well be going too fast, move out into a space that isn't really wide enough, and then brake suddenly.
Still, in my experience these don't cause much delay if you're allowing a sensible gap in front. I find people who try to keep closer to the car in front to deter others from pulling into "their" space seem to get far more upset about these situations than I do.
Reminds me of the George Carlin line: "anybody driving slower than you is an idiot, and anyone going faster than you is a maniac"
If you leave a large enough gap with the car in front, then people will merge into that gap. If you then slow down to create a new gap - people will overtake and merge in again. You end up travelling slower than the rest of traffic, with people overtaking and merging, which creates dangers in itself.
In Germany, this is legally required. However, the safety distance is often abused by other vehicles when passing.
Unless the tailgater also has this system!
You don't erase the standing wave by having everybody maintain a fixed following distance or mimicking the speed of their leader. You need to predict future changes and allow the space to contract to help smooth out the transient disruptions and slowly rebound without over-shooting. You want each following car to react less than the previous and have a weaker deceleration/acceleration curve.
Unfortunately, I have noticed increasingly absurd feedback loops in long distance routes here in CA. As a user of conventional cruise control, I can't help but notice how frequently I now have to intervene to adjust speeds in relatively light traffic conditions. On long drives like LA-SF via I-5, these yo-yo drivers are my new nemesis. I don't know if it is due to their use of adaptive cruise controls or a more basic loss of attention or self-awareness. For example, I see packs of cars with speeds oscillating between 55-80 MPH when conditions should easily allow a steady cruise at 75 MPH.
One of them thinks I will drive into a wall when I’m approaching a 90degree turn with a wall. Does the break check from time to time. Nothing weird at high speeds for now.
Other had a single break check at high speed, there was nothing in front so the sensors somehow messed up I guess. It braked for something like 100ms, at least it felt like that. Then kept driving normally. But even that was scary.
This is to persuade you to also buy a car with new brake tech ;)
You've just explained why autonomous braking is completely unnecessary. People are perfect, never make mistakes and never assume that the car in freely-flowing traffic ahead of them won't stamp on the brakes for no apparent reason.
This could be either because they are distracted (eg. fidgeting with the radio or their mobile phone), or because vision is poor (dense fog).
A system that warns you in those cases that there's a vehicle in front of you sounds useful to me.
I'm in two minds about vehicle automation. Most of it is to compensate for human idiocy (such as the above example). The same gains could be made by humans not doing illegal maneuverers like that. Yes, there are occasions where the electronics can react appropriately to a rapidly developing situation much faster than a human could (e.g. child/animal running into the road), but I agree with the article's caution on complacency. All it needs is for a driver used to auto-braking to get into a car without it and cause an accident, and the technology will suddenly become mandatory.
At the other end of the spectrum, as I've often said, it's technology developed by humans, based on our own understandings, so there will be flaws. Having experienced poor ABS systems that would activate at low speed to the point that I feared the car would not stop at the junction I was approaching, I am not confident auto-brakes will react appropriately in every situation they're called upon.
A lot of vehicular automation is compared to aircraft systems (especially fully autonomous technology) but there is a critical distinction - you never get tailgaters in the air (or if you do, something has gone terribly wrong). Aircraft can rely on huge amounts of automation because in normal use, there are huge amounts of open air in every direction to allow the pilot time to take back control should the systems fail, and still have space and time to correct the immediate problem. Vehicles on the ground are tightly grouped together. Not only does this leave precious little time for humans to react to a bad situation, it also means that any automation systems are similarly constrained. They have to work correctly in a span of seconds or milliseconds. There is no time to 'nope' out and pass control back to the human when they exceed their programming, as is frequently the case with Tesla. Failure is thus very difficult to analyse and account for.
Automation is generally a good thing, but I can't help thinking we might end up automating ourselves into a hole on this one.
I've since learned to move around whenever I'm looking for other vehicles.
Why not do so before the merge check?
The driver in Car A is a new driver, and is uncomfortable merging. The lane they would be entering is clear, but they're spooked by the car in the far lane and stop unnecessarily at the merge point.
The driver in Car B behind them is following closely and is preparing to merge by doing a shoulder check. They are not looking forward when the car in front of them stops. If the way had been blocked they would have been expecting the car ahead to stop, but they had seen it was clear.
The driver of Car B is at-fault in that collision. They were depending on the driver ahead of them to behave predictably, and they were not driving defensively enough. A warning noise would probably have triggered them to slam on the breaks and might have prevented the collision. Automatic emergency breaking would do the same, perhaps more reliably.
(This was a real accident. I was a passenger in the lead car.)
They didn't do tests with drivers inexperienced with the system?
Sometimes, rules and regulations actually do improve things :)
One of the most unnerving drives I had to do was traveling on the Ohio Turnpike in super-dense fog. The traffic was heavy but moving more or less at speed. Cue the toll plaza... and the need to reform two lanes of traffic, with slowly accelerating truck traffic, cars whizzing from the right to pass the accelerating trucks, all in dense fog with almost no visibility (I don't think you could see the rightmost toll lane from the leftmost). And one idiot didn't have his lights on.
Final safety tip: if you can't see the road very well, turn your lights on. Even if they don't help you see the road (which they don't in fog), they absolutely help everybody else see you.
A combination of wanting to get to your destination on time, inexperience and overconfidence are probably the key reasons.
Turned my lights on to avoid being hit, seemed to work - or maybe I was just surrounded by cautious drivers that day.
The problem is that the XC90 got its AEB in 2015. This cannot be the reason for the impressive safety levels since 2002.
It's just physics. When large a object meets a small object then the large object wins because it has more energy and ends up pushing the small object backwards.
It is not that improbable that midsize luxury SUV that sold just 50,000 cars in the UK since 2002 had no driver deaths.
AEB was first installed in the 2015 model year. If we assume that the same number of cars were sold each year, the XC90 had 20,000 registered vehicle years with AEB. We should expect 0.03 deaths.
It would be more surprising if there was a driver death in a Volvo XC90 equipped with AEB in the UK.
 http://www.iihs.org/iihs/sr/statusreport/article/50/1/1 (first table)
 It's probably false, adjust with your favorite fudge factor.
If you look into the data on fatal accidents and examine them even for a few minutes you'll easily see that this is a foolhardy bet. The causes of accidents and fatalities are highly variable and not what you would expect. There's also extreme variability between the individual states; for example, Texas has more _total_ fatalities than California. There's extreme variability between the sexes and for different age groups within those sexes. Finally, there are motorcycles.
AI/Driverless, AV and all the attendant sensors and inputs will have an impact, just not nearly as large of one as many people unfortunately expect.
Would a decrease in some types of collisions be a reasonable assumption under the grandparents premise?
Personally I downloaded their database and then converted into an SQLite database that I could run queries against. They do have an online tool, but I have no experience with that.
Quoting the linked article:
At the moment, most AEB systems are "forward-looking". In other words they are designed to prevent crashes where one car runs into the back of another.
Such crashes account for around a quarter of all accidents, but these are the incidents which can cause some of the nastiest injuries, such as whiplash.
AEB has been shown to reduce such collisions by 38%, according to research by the safety organisation Euro NCAP.
Absolutely, I wish every prospective motorcyclist would study the stats (more than 35 times increased mortality rate per driven km ) and discuss this with their loved
Those who insist driving a motorcycle afterwards deserve their genes to be removed from the gene pool.
So, I suggest to take the risk-taking elsewhere: go climb a mountain, do base-jumping or take the motorcycle to a racing track (bonus: real competition!). But leave other motorists out of your game.
Severely deficient mandatory motorcycle training, riders who refuse to wear helmets or any safety gear at all, a tendency to just go for the biggest most powerful engine right away, and of course shitty drivers, who either deliberately antagonize riders, or simply don't give a shit.
Squids and outlaw bikers heavily skew the numbers.
All I am saying is: it's fun to enjoy a sport, I get it. As a top-roping climber, I also empathise with the thrill of adrenalin. But I just did the numbers: an average motor-cyclist will have a 6% chance to be involved in a serious motor vehicle accident in his lifetime, causing extreme trauma. 50% of those accidents involve other drivers. Think of them. They did not choose for cyclists driving 200 kph while overtaking through the middle. Did that cyclist take that other driver into account when he lays there on the tarmac? Did he take into account the years of psychological trauma he caused by his reckless behaviour?
You don't have a bike license, do you? Your line of reasoning is very consistent with car drivers who are a bit afraid of traffic, and very afraid of "murdercycles".
It also has front sensors which has alerted and braked for me a couple of times when someone has almost stopped dead at 60MPH (even with stopping distance, it was a quick stop).
In my car you can manually give it the gas when changing lanes and accelerate faster than by ACC without disabling ACC. Maybe your car allows that too?
i.e. a strip of light across the rear of the vehicle, that progressively lights up according to how hard the vehicle is braking (or anticipates braking, if it's autonomous).
Some cars have a flash-brake-lights-under-heavy-braking, but I think it would help traffic flow if you can more easily distinguish a touch of the brakes from a press of the brakes.
Interesting to note, though, that we do have weak forms of braking that don't light up the tail lights - heavy engine braking in the case of manual transmissions, lighter engine-braking for automatics, and in the case of electric vehicles (at least a Tesla in my experience) the lights don't kick on from regen unless it's passed a certain deceleration level.
What exactly do you get from incremental brake lights?
I put a lot more faith in sensors to judge the distance to the car in front of me, than my visual perception of brake lights. At a certain medium distance, I'm sure I wouldn't be able to judge the difference between 25% brake and 75% anyway, but my car's sensors would be able to detect that I'm on a collision course, and could adjust gas/braking accordingly.
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.
First rule of winter driving is don't touch the brake.
You can absolutely brake, you just have to be smooth and gradual.
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.
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.
The other thing is to accelerate through turns - it helps maintain traction.
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)
That's not the ideal outcome but it's still a net win, no?
So from a safety standpoint, that is a not a win.
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.
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.
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.
"Vision 2020 is about reducing the number of people that die or are seriously injured in road traffic accidents to zero. "
As sceptical as I am about corporate statements, you can see that Volvo is steadily working on this. They don't do splashy announcements or announce revolutions in driving, and yet they bring more and more changes and improvements to their cars. From assisted braking to lane assist to blind spot information to city collision avoidance to many many other small and big improvements.
I would disagree with that statement!
As an urban cyclist the two most terrifying vehicles on the road for me are the XC90 and the VAG PL71 ( Q7, Touareg, Cayenne ) not only because of their size but also because they are predominently driven by distracted parents on the school-run.
Two tonnes of SUV, poor outward visibility, stressed driver looking for a parking spot on the kerb, kids bickering in the back == danger.
I can understand parents buy them to keep their little darlings safe from the other nasty cars but I'd much rather jostle with twice as many normal-sized sedans.
> not a single person has been killed while driving it, or as a passenger.
It doesn't say anything about no one killed by the XC90, which is quite, ahem, surprising for an article touting AEB.
The XC90 T8 was tested at 5.0s here, which is pretty good for being a review test and not a manufacturer figure
Now, the T8 is expensive as hell obviously (~$70k and up) and competes with other big hybrids, not the base spec Q7 3.0TFSI. Most of thesre aren't sold anywhere near msrp, at least around here they usually go for nearly $100k with extras.
So the XC90 has a pretty reasonable 315hp T6 version that competes directly with the Q7 (But is around 1 sec slower 0-60) and one 400hp T8 version that is going to look pretty good next to any of the big X5/Q7 suvs in performance. I think it's a pretty reasonable set of trims.
Slow down, stop stressing, live longer.
Aside from Jeremy Clarkson of course, who's bought like every generation of the thing
Although it's not their fault for the crash, celebrating the safety of an SUV, when it's size and extra weight means that crashes with pedestrians will more likely end in death, seems odd.
Volvo introduced Aeb in 2007 on the XC60. The XC90 only got it when they introduced the new generation a few years ago. Therefore claiming that the exceptional safety record of the XC90 is in any way related to AEB is just rubbish.
The reason why XC90s are associated with so few passenger injuries (note, no claims are made for injuries to other road users by XC90s) is that they are large, heavy and chosen by safsr-than-average demographics.
Also, I can imagine additional advantages of AEB. If someone's tailgating, just hit your brakes enough that their AEB will trigger.
> in the period 1991-2001 [...] about 109,000 lives were saved by belts and 8,000 by airbags
so I guess seat belts were a bigger improvement.
Also airbags depend on seatbelt use to be effective, and some of them have killed people.
In what world is it better to NOT have airbags?
Remember the takata airbag defect killed 15 people in the US. https://www.consumerreports.org/car-recalls-defects/takata-a...
Not by a long shot - seat belts reduce the chance of death by 60-70% across all crashes. Airbags reduce the chance of death by 15% in frontal collisions, and very little for other types. The airbag isn’t going to much good if you’ve been ejected from the car.
That’s why modern cars try to avoid firing them unless absolutely necessary. You can get into a pretty serious crash and they won’t fire if the computer decides its better to let you gently tap the steering wheel than to run an expkosion into your face.
Fun example of an old and new Renault Espace crashing into each other: https://youtu.be/vRxLlFm3VUA
Not to mention the current situation with Takata, where they have had instances of their airbags directly killing people due to a failure of the metal housing, which turns to shrapnel.
That depends on how you count: no life saved by an airbag would be saved without airbag AND safety belt. An airbag alone saves no lives.
And I still doubt the airbag+belt combination made a bigger dent in the statistic than the introduction of the safety belt did (Although it's hard to compare due to completely different time periods)
I did mean seat belt + air bag vs seat belt alone. But even then, air bags apparently improve seat belt protection by less than 20%.
I was thinking of dramatic high-speed frontal collisions with ~immovable objects. Where forces from seat belts alone can cause damage.
It does beep randomly sometimes - usually in heavy rain. But that one time it turned on pretty late, so it's a good last resort.
I think this is a combination of great safety equipment, the safeness of the car itself (crash tests and so on) and the people who buys it. Its not the most hardcore drivers who buys a Volvo, even tho the 2017 and newer models are really good looking. Volvo has always been a pioneer in security as well
I'd rather ask, would the Volvo system steer towards the barrier like Tesla's AP may have done  ?
"IIHS research shows that AEB systems meeting the commitment would reduce rear-end crashes by 40 percent." 
AEB on its own may save lives. Whether autosteer systems do or not is an open question.
1) Do other autosteering systems (such as Volvo's) share this failure mode? (I don't know much about Pilot Assist but it seems to require a lead car to follow, is that right? Apparently Pilot Assist 2 doesn't, though? Currently reading http://forums.swedespeed.com/showthread.php?348321-Auto-Pilo... and it doesn't sound great.)
2) Should AEB stop the car if there's something solid in front of it, regardless of what the autosteer system is doing? (I would have thought so, and it's disappointing that in this case it didn't!)