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Discussion Starter · #1 ·
I got a report from my wife today of some odd, potentially dangerous, behavior with the ACC system.

She was following another car down a straight road and had the cruise set at 50. The lead car was going slightly under 50 so the Ascent locked on (green HUD light) and followed at that speed. Conditions were slightly rainy. The Ascent then started to intermittently "forget" and "recognize" the lead car as evident by the HUD light turning off/on and an increase/decrease in speed. After a couple cycles of this she turned off cruise and manually controlled speed so as not to chance a rear end collision.

I've experienced the Eyesight system turning off in heavy rain which is reasonable. This is the first time it's been on though and completely missed the lead car. I assume that pre-collision braking would also not have functioned.

Has anyone else experienced the same? Any suggestions?
 

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Straight road following seems pretty consistent for me. Do you know what the following distance was set to?
 

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Follow distance setting shouldn't change vehicle acquisition and lock. Just to get these out of the way, are there any coatings, windshield mounted objects, dirty windshield, Rain-X (or similar) washer fluids, tints, etc?

Also, I found, for one thing, I needed to clean my inside glass (a few times now), due to that nasty white off-gassing residue. Won't affect the camera lenses (don't clean those), but does affect the cameras seeing through them.
 

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Discussion Starter · #5 ·
Follow distance setting shouldn't change vehicle acquisition and lock. Just to get these out of the way, are there any coatings, windshield mounted objects, dirty windshield, Rain-X (or similar) washer fluids, tints, etc?

Also, I found, for one thing, I needed to clean my inside glass (a few times now), due to that nasty white off-gassing residue. Won't affect the camera lenses (don't clean those), but does affect the cameras seeing through them.
There's nothing goofy going on with coatings. We do have a toll pass attached but it's in a bottom corner in the "safe" area. I'll try cleaning the inside though it's not noticeably dirty. Behavior has been normal since originally posting. I'll update if it happens again. Thanks for the suggestions.
 

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... I'll try cleaning the inside though it's not noticeably dirty. Behavior has been normal since originally posting. I'll update if it happens again. Thanks for the suggestions.
Make sure you don’t clean the cameras themselves, just the window glass.
My train of thought with the following distance was that if it was set at max and raining it might lose sight between wiper swipes? If so it should eventually disable eyesight based on conditions but set at 2-3 I doubt that’s much of a factor.
 

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Per Robert Mauro, the follow distance setting does not affect detection distance. This is evident when I use the CC in good conditions as it will detect and indicate a vehicle far ahead irrespective of the follow distance I have set.
 

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Per Robert Mauro, the follow distance setting does not affect detection distance. This is evident when I use the CC in good conditions as it will detect and indicate a vehicle far ahead irrespective of the follow distance I have set.
what if that car 4+ lengths ahead doesnt have lights on? just saying it could be a factor. eyesight is good but not perfect
 

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Yeah. I'm not saying there isn't variability with conditions, just that there isn't variablity with the following distance setting. The following distance setting doesn't affect how far ahead and whether or not a vehicle is detected. That's independent of the follow distance setting.
 

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Vehicle and object acquisition isn't directly related to ACC follow distance setting. It's always trying its best.

What does affect vehicle acquisition are speed differentials, so, for instance, if the car in front of you is acquired already, but moves out of the way, exposing a car that's going much slower, the system will take longer to acquire it. It's easy enough to see why if you (as a passenger of course) try to take a video of a vehicle in front of you that is traveling the same speed, and then take a video of one parked on the side of the road. Freeze frame and step frame by frame through both.

So... how does ACC settings affect it? Well, if ACC follow distance is greater, in scenarios like my first one above, it has more time to recognize and acquire a car simply because it has more distance to do so.

In the event it does not recognize and acquire it in time, then pre-collision braking will take over, first warn you, and then, apply the brakes. Those two systems work pretty independently. Every now and then (such as in my scenario, or, when the person in front of you does emergency braking) you may notice that ACC decelerates to try to match speed, but pre-collision braking decides that ACC may not be braking quick enough, and will set off the PCB alert.

On a related note, Lane Keep Assist and Lane Departure Warning also work independently, which is why even when LKA cannot determine a lane marking with sufficient confidence to help out, LDW may still alert you to what it perceives as a lane departure.
 

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^^which is why it annoys tf out of me when people in front of me wait till the last minute to hit their brakes for something! this causes me, on acc of course, to abruptly slow down too. if i anticipate their slowdown i'll give myself a headstart by increasing following distance which causes a temporary slowdown, which turns into actual braking when the vehicle i'm following finally hits their brakes.

anyway im not disagreeing with anything you stated about how it works; eyesight is always looking for an object ahead independent of acc on/off or its distance setting. i think our brain wavelengths are slightly out of sync though. as an object gets farther away it appears smaller, therefore harder to see. so under some circumstances at the edge of eyesight's view it should be plausible it could lose sight of the object.
 

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anyway im not disagreeing with anything you stated about how it works; eyesight is always looking for an object ahead independent of acc on/off or its distance setting. i think our brain wavelengths are slightly out of sync though. as an object gets farther away it appears smaller, therefore harder to see. so under some circumstances at the edge of eyesight's view it should be plausible it could lose sight of the object.
Right, but that should be well outside of the follow distance - except of course where weather or environment play a factor, in which case, it will eventually fault off. But, I have seen a couple instances like the OP, on dreary, rainy, days, with certain color cars that kinda blend in.

The car also seems to make different judgment calls as to what a car is, for the purpose of high beam assist. It's really impressive seeing how accurate that is over great distances.

I once got a brief glance at the system "info" in action during some demo or diag session. Really really neat stuff.
 

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The car also seems to make different judgment calls as to what a car is, for the purpose of high beam assist. It's really impressive seeing how accurate that is over great distances.
I'm very impressed with the automatic high beams. We don't drive a lot at night, but the car hasn't once missed an actual oncoming car, and false positives due to reflectors or road signs are very minimal.

EyeSight is totally fascinating to me, especially the software programming behind all of these driver assist features.
 

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I'm very impressed with the automatic high beams. We don't drive a lot at night, but the car hasn't once missed an actual oncoming car, and false positives due to reflectors or road signs are very minimal.

EyeSight is totally fascinating to me, especially the software programming behind all of these driver assist features.
You have no idea how much I want to see the BTS developer stuff on the new systems. To have gotten a glimpse at the original stuff was a treat!!!

I wish they'd invite me to Japan and let me roam around their development labs for a few weeks. :ROFLMAO:

(Subaru, I'm not joking... seriously... invite me over!!!)
 

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Finally got to use the auto dim system this last week as I drove to work early each morning. No problem with oncoming traffic, but a couple times they would dim when approaching bright(probably LED) farm yard lights. They also stayed dim too long, when a car passed me. The lights would go to bright whenever the car would disappear over a hill, but would dim when it saw the tail lights again, even up to almost a mile away. This is on a rural two lane, with very light traffic.
 

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Discussion Starter · #17 ·
Great discussion so far.

All bets are off in the rain, be it heavy or light rain.
This is understandable as it's an optical system that is being obstructed by rain and wipers. My main gripe though is that if Eyesight can't function reliably at times, shouldn't it fail safe by disabling and alerting on the info screen? It's scary that there's an outside case where it doesn't detect something right in front of it and thinks the path ahead is clear. I'm not giving up on the car or system yet. For me it underscores the fact that this is a driver assist and we still need to be alert and ready to take action.
 

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Great discussion so far.

This is understandable as it's an optical system that is being obstructed by rain and wipers. My main gripe though is that if Eyesight can't function reliably at times, shouldn't it fail safe by disabling and alerting on the info screen? It's scary that there's an outside case where it doesn't detect something right in front of it and thinks the path ahead is clear. I'm not giving up on the car or system yet. For me it underscores the fact that this is a driver assist and we still need to be alert and ready to take action.
Only if it can tell if it's impeded. That's the problem with computer systems. They don't understand enough about the world around them to make those judgments yet.

For instance, the car computer doesn't know the difference between the front windshield being tinted and a dark night with no street lights. And, when it can't see something (because of either condition), it doesn't know it can't see that thing - it simply thinks there's nothing there.

Humans do a ton of judgment calls and theorizing. We can tell the difference between fog, a dirty windshield, an overcast day, or tint that we know we did or did not put on our windshield. With that knowledge, we can also keep track of where we think vehicles would be and prepare accordingly.

Heck, a perfect example is that we can see the barest sliver of a car in front of another (or even through the other's windows), and note that it slammed on the brakes, WE know that the car directly in front of us is likely to jam on the brakes as well. We thus prepare accordingly. Cars today can't even figure out that the little sliver of something is another car, much less understand that the tiny bit of red means that sliver is doing something it might really be interested in.

We can follow cars around bends - whole rows of them - and anticipate actions. The car computers need to see lines, clearly delineated objects (vehicles), etc, to know that the car in front is still in the same lane. It's intuitive for us, and it's difficult or impossible for them.

Which brings us back to your key point, which I am always happy to see reiterated.
For me it underscores the fact that this is a driver assist and we still need to be alert and ready to take action.
Sadly, there's no consumer available Level 5 (or even Level 4) autonomous vehicles on the market yet, but too many people act like there are, and thus cause accidents, or gripe when the system doesn't do what they want.

There was actually someone in the group who went on a horrible, curse laden tirade, about how the Ascent almost killed his wife and baby because it almost crashed into something while she was busy changing the diaper of the baby in the back seat. It apparently jammed on the brakes at the last second and saved them from an accident. The key point I haven't mentioned yet is, only her and the baby were in the car - and the baby was obviously not the driver. But, sadly, neither was she. Some of you who've been around from the beginning of this group may remember that. Numerous of us tried politely explaining what the system was designed to do. We got lots of profanities in return, much of which I deleted as quickly as possible.

For now, every system in the country in every vehicle available for consumer purchase, comes with only a driver assist system, if they come with anything at all.


Personally, I cannot wait to get in a car and fall asleep while it takes me where I need to go - without the need for a driver. I utterly love driving for fun or adventure, but I hate driving in rush hour traffic - which is about half of my driving. ?
 
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