Euro model's AHS Adaptive high beam system

I agree that the optical speed limit sign recognition is inefficient and prone to spurious false indications. A Mickey mouse system for idealised roads that don't exist.

From various threads regarding some chips, etc. I think the screen glass may be too thin for rain detection. At least until someone who understands these matters come along and puts me straight!

 

btw., it is not offered in US (for Prime)

 

I don't believe the new AHB-System on Prius PHV will use the same camera as the regular Prius,as it has to check on upcoming cars as also on cars ahead keeping them constantly in the shadow and not dazzling them while the rest of the road can be still lit up with high beam,so maybe,with a better camera,also the RSA will perform better !?

 

Ahem . . .

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I've heard others state that in USA the speed limits are embeded in the satnav data.

 

Yes and they are in Europe too,but the saftey sense camera on European Prius/Prime can also read the speed limits as the car passes them,sometimes leading to a confusing situation as road map data and the poor reading capability of the camera show two different speed limits...

 

Amazing technology, I hope it eventually makes it to the U.S. Watching the French video you can see when there is oncoming traffic it selectively darkens just the area ahead and to the left while keeping other directions fully lit.

However it also seems overly sensitive to oncoming traffic far in the distance. Although I am basing this on just one observation in the French video

It's on a part of the video in a straight stretch of road, seemingly in the country away from any street lights. At 3:33 an oncoming car passes by, and as expected after the car passes it immediately resumes illuminating the area ahead and to the left (which I will call AL for brevity). In the far distance you can see the dot of an oncoming vehicle. But then at 3:40 it darkens AL even though the oncoming car still seems far away. A 3:59 the oncoming car dips below the horizon and AL is illuminated again (ignore what appears to be the car coming back up at 4:02 as that turns out to be just a street sign). A 4:22 the oncoming car, much closer now, pops up over the horizon and AL immediately darkens as it should. The oncoming car passes by at 4:31.

But that means it stopped illuminating AL at 3:40 because of a car that was 50 seconds away! I can't gauge the exact speed they are travelling but I am guessing the oncoming car was almost a mile away at that point. The law says you should dim your headlights for any oncoming vehicles within 500 feet (1/10th mile). For courtesy I usually dim sooner than that, but not a mile!

I realize I am basing this on watching a video, and I could be misinterpreting, but the question is how well does it gauge the distance of oncoming traffic? Is the sensitivity adjustable? In case it dims too early, I guess you can just flick the brights on, but then does it fight with you and keep turning them off?

Not trying to bash, just trying to get a feel for how well it works, and how easy is it to override temporarily when needed. Sort of like cruise control, one click and you can disengage, another click to resume. Is it the same with AHS?

 

I would say, regarding to the AHS sensitivity settings we can rely only on practical experiences ... fortunately, GT4Prius/RCO are very satisfied.

For example, here is another video (US LEDs) with better FHD quality, not moving, and an author can see 15 trees against about seven trees in video:

According to my personal experience the oncoming high beam can be distracting from a long distance. Moreover, take into consideration 27 countries in EU with the different regulations

 

Please don't think I'm rubbishing the Prius, I most certainly am not! The regular inaccuracies of the sign recognition is a nuisance at times, so I wish there was some way of turning it off.

For example, I'm driving along a UK dual carriageway with speed limit of 70mph when the camera sees a speed sign to the left on another road of 40mph and thereafter fails to correct back to 70 again. Same thing with truck limit signs and billboards, too many errors creep in to dilute the overall efficiency of the system. I still think the Prius is great, but to have an incorrect speed warning on the HUD replace the power gradient graph is a bl**day nuisance and that is my personal opinion. YMMV.

 

I agree that if AHS will by algorithm decide to turn off high beam (and actually you need high beam), then it takes a time to find the switch to turn off AHS and maintain high beam. So, it could be arranged a faster way. On the other hand, to avoid a dazzling effect with AHS on is very practical and fast, just to push/pull a lever.

Generally, AHS is a big step in night driving safety. I've checked the IIHS crash test results for Prius Prime: 2017 Toyota Prius Prime
See Headlights section, low beam left side is approximately four times shorter as high beam left side. Following, AHS can provide up to four times (!) better visibility of the left side and up to two times better visibility of the right side.

 

But that cannot be the solution!
It should be no problem at all for Toyota to update the systems software,but if people just turn off the RSA instead of complaining that's not likely to happen !