ydooby

I'd like to raise awareness of the Predictive Forward Collision Warning system (PFCW), an innovative world-first safety technology developed by Nissan/Infiniti back in 2013 when the Q50 was released.

What PFCW is, is a radar that monitors not just the car directly ahead of you, but also the car ahead of it, the view of which is often completely blocked to you if the vehicle directly in front of you is wide and tall. When the car ahead of the car in front of you suddenly brakes, the PFCW system would immediately make an audible warning before the car directly in front of you even reacts, which gives you that much more time to mitigate a potential crash by braking or making a lane change early, or allows you to the brake much less harshly/emergently than if you had reacted only after the car in the front reacts.

Among all the plethora of driver-assist technologies available today PFCW is the only one that I would not find useless just because I drive responsibly and always pay full attention while I drive. Consider the following scenario: I'm driving on a straight stretch of highway, maintaining a "safe" following distance to the car in front of me, meaning that the distance I maintain is enough for me to stop my car in time if the car in front of me suddenly brakes in full force given the speed we are traveling at. However, the car in front of the car in front of me, which I cannot see, suddenly brakes in full force, and the car in front of me doesn't react until it almost crashes, when it finally evades by changing lane, leaving a fast-decelerating car now exposed to me. What had been a "safe" following distance suddenly becomes unsafe because it was assumed that the car in front of me would suddenly brake only from the same speed I was traveling at, but now instead the car in front me is decelerating from a much lower speed at the same presumably safe distance, leaving less room than is required for me to stop and avoid a crash in time. And if there happens to be cars next to me, blocking me from changing lanes, a crash would then be inevitable--all while I was driving responsibly and reacting as quickly as humanly possible. With PFCW I would've been able to react at the moment the car in front of the car in front of me started to brake suddenly and not rely on the car in front of me to react.

And what truly impresses me is how this technology is achieved. Normally it's impossible for radio waves of a radar to penetrate the car directly in front to detect anything ahead of it, but how Nissan/Infiniti implements it is to mount the radar behind the lower grille of the car, therefore allowing it to "see" through the car in front by beaming radio waves underneath it. I don't know about you guys, but that's a real stroke of genius to me.

Now, it's been 5 years since PFCW made its debut on the Q50, and other than Nissan's own vehicles, I have yet to see it adopted by any other automaker at all--why is that? Is it not as valuable as I thought it is? Every other driver-assist safety technology I've seen in the past two decades (and Toyota/Lexus came up with quite a few of them) has always been quickly adopted by at least one or two if not many other auto makers in a couple of years after debut, but why not this one?

Discussion please.

How it works:

How it's implemented:

S2000toIS350

I have a 2014 Q50S Hybrid AWD with the system and it does work well, unless the sensors are covered in snow and the system becomes unavailable.

Question is, since the system is MobileEye based, do other car brands have the same thing with other nomenclature?

ydooby

Indeed, the fact that the radar has to be mounted at the most vulnerable part of the car is a major shortcoming.Pretty sure Nissan/Infiniti developed this one on its own as this implementation has never been mentioned by Mobileye or any other automaker, which all can do the "monitor the car ahead" part but not the "monitor two cars ahead" part.

theory816

A lot of these innovations are expensive and unnecessary. The best tech? Its you. Almost all rear end collisions can be avoided if you keep the correct following distance. I can go on.

Btw, was at the DMV today and I saw a grandma with walking canes try to renew her license. She failed. Just amazes me that no one is taking her around and that she needs to drive herself.

ydooby

Well I actually provided a scenario in my post where a collision can't be avoided even if you keep the correct following distance. It's why I find the PFCW system invaluable and not some tech that's only useful to distracted drivers.Hopefully level-5 self-driving cars will arrive sooner than later for her.

Fizzboy7

I'd prefer none of these nannies be added. A driver who pays attention and makes driving the #1 priority can and will make the proper corrections when needed. Such nannies are actually a hazard to those who take driving seriously.

Sulu

I remember reading that Nissan discovered this by accident (so any automaker could do this, if they wanted). Nissan did not go about with the intention to design a collision warning system that could see 2 vehicles in front. Having aimed the radar transmitter too low, the Nissan engineers were surprised to find that their collision warning system detected the vehicle in front of the one that they were immediately following. Only upon further analysis did they find that the radar signals were bouncing off the ground under the car immediately in front.

That said, this system is not going to work as expected (detect 2 vehicles in front) if the vehicle immediately in front is too low, if the vehicle is too long, or if you are following a fair distance behind the vehicle in front. If you are following a fair distance (which you should be doing, regardless) from the vehicle in front, which gives you distance and time to react to the brake lights of the vehicle in front, you don't need Predictive Forward Collision Warning.

I always follow a fair distance behind the vehicle in front because it gives a much smoother ride (and saves undue wear on the brakes) since I am not constantly off the accelerator and on the brake every time the vehicle I am following slows down.

ydooby

Thanks for the interesting tidbits. I guess the limitations of this technology as you listed are the reasons why it hasn't seen a wider adoption. Too bad the laws of physics can't be defied after all.

theory816

I reread it and it still comes down to your following distance and your speed. Maintaining the speed limit also helps tremendously in your reaction time. Most people go 5-15mph over on the highway and I think this is wrong. You should ALWAYS go the posted speed limit. Thats what ive learned from road engineers.

S2000toIS350

evident

not a fan of most nanny systems either but op described a situation where this works. Also, am a fan of bsm on vehicles.

theory816

I get what you are saying but it still doesn't matter if the 3rd car has stopped and the 2nd car swerves out of the way. Your following distance should be adequate enough to react to any object in front of you.

So its break down like this: You------------------------------------------------------------------------------------------------2NDcar-----3RDobject/car
Even if the 2nd car dodges at the last minute, you still have plenty of time to react because of your speed/distance/reaction time.

With this distance, youll hit the 3rd object for sure:

You---------------------2NDcar -----3rdobject/car

But in all honesty, the software is good. Not everyone has good driving abilities. I can see it saving a lot of headaches.

signdetres

I had this feature on my previous Infiniti Q50S and it very rarely came into use. There were a couple of times where it went off throughout my course of ownership that were very cool moments where I jumped on the brakes before anything happened and either the car in front of me then began to slam on their brakes or either abruptly changed lanes revealing stopped cars in front of them.

There was one particular instance when I had nearly just gotten the car where it actually saved me from being involved in a 4-car pileup. I had been using Waze for directions rather than using the in-car navi and had glanced down for a split second to see where my next turn was and in that moment, I heard a single "ding" go off (it was a different chime than the collision warning system), looked up and the second I looked up, the giant Suburban in front of me (that I could not see around) slammed on their brake, as did I and the car behind me. Literally stopped within inches of hitting the Suburban, the S-Class behind me also nearly stopped within inches (both of us had initiated that swerve to the side you do when you think you're going to hit the car in front and are trying to do anything possible to avoid). The Suburban had actually rear-ended the car in front. I was shaking afterwards, it was a pretty scary situation that happened so incredibly quickly. I had nearly just wrecked my brand new car and I would have if it weren't for the safety systems on-board.

That said, now that I'm slightly older but much more mature, I can look back in hindsight and say I drove that car like a total d-bag. Now that I have my GS, I enjoy the dignified ride as well as the overall smoothness and refinement and like to glide around in Eco mode. I don't speed, I don't engage in road rage, I'm courteous to others and I maintain a safe following distance. I also use the in-car navi system and keep my phone in my pocket at all times while driving. I echo what others have stated. If you drive properly, safely, & attentively, you really don't need any safety systems to save you as you have time to process and react to any situation.

Anyway, here's a video of the system in action for anyone curious. Not my video but I can give a little context to what's happening as it all happens quickly and you're not able to see the instrument cluster:


At the 3-second mark, the single "ding" you hear is predictive forward collision warning going off. Then you see the truck begin to brake aggressively. Just before the 4-second mark, the multiple chirps or beeps you hear are the first stage of the actual forward collision warning alerts.

ydooby

In reality, keeping such a long following distance only means people behind and next to you will keep swerving around you and cutting in front of you, and you'll simply end up having to keep slowing down to maintain your extra long following distance. I see PCFW as a tool to allow me to follow at a distance much more agreeable to people around me, without having to worry about the actions of potentially hidden cars ahead of the car in front of me impacting my safety.

scooky

While it may rarely be used, it's kind of like airbags. Ideally never used, but when used it was probably an important moment with some alternatively poor outcomes.

My current RC is the only car I've had with any of these features. I'm glad they are there. However, the manual is super thick with pictures explaining where these systems may fail to function as designed. Tunnels, turns, hills, flatbeds, etc., etc., etc. While I'm glad it's there, I'm NOT counting on it to save my hide if/when the time comes. But it might so I'll take it.

The version found in the Infinity is interesting, but I would count on it even less. Soo many scenarios where it wouldn't get the job done. But then if it has 0 false negatives, and saves a few collisions maybe it's worth it. I don't think I'd make it law or exclude a purchase because a vehicle didn't have it. I wouldn't avoid it either.

fwiw: different thread, but I am totally not ready for self driving cars. Either as a driver/passenger, or as someone who shares the road with them. Especially when I'm on 2 wheels. Someday I expect they will be awesome but, like a lot of tech, the adoption process could be troublesome.