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Auto lane change "randomly" refusing to work

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In a previous post (see: My silky smooth 320 mile road trip with almost 100% AP control), I mentioned that several times on my trip I could not use auto lane change. I'd signal and...nothing would happen. But other times it would work fine. All total, I'd say about 65% of the lane changes worked and 35% didn't. By the time I did the return trip documented above, I had at least figured out WHEN it would work or not work. I'm sharing this with you guys in case this is news to anyone. Maybe everyone already knows this though and it is only news to me.

Anyway, I discovered that when the binnacle display shows an adjacent lane, auto lane change will work. When it does not show an adjacent lane, auto lane change will not work. So while on the first leg of the trip, it seemed totally random, in actuality it was deterministic.

In cases where I was on a 3 lane (or wider) stretch of highway, sometimes the display would show a lane only on one side (example, left) but not the other (right). As you can probably guess now, it would allow me to auto-lane change into the left lane but not the right.

While I can understand the logic that if it thinks there is no adjacent lane, it shouldn't stupidly and blindly move into a lane it doesn't think exists (or is oncoming traffic). But my questions to you guys are:

A) Any ideas why the cameras/sensors don't "see" adjacent lanes consistently? This happened in broad daylight on Highway 101...not exactly a seldom travelled road nor poor weather conditions. Plus fleet learning and the video clips and all...I'd think this would be pretty locked down/mapped out, especially on major thoroughfares.

B) Has this always been the case? Or maybe a recently introduced bug/issue in the latest firmware? Anyone else seen this 'forever' or maybe more recently?



Seeing this image, I know I can auto-change lanes (either left or right in this case)
IMG_0111.jpg


Seeing this image, I know the car will NOT auto-lane change. But you can see there is indeed a lane to the left of me
IMG_0119.jpg
 
repeat as necessary:
it's only a beta
the system is far from perfect and every once in awhile external issues will cause the system to do odd things like this. for example sometimes the angle of the sun will affect how the camera sees the road and will render the AP inoperative. have no fear but when the angle of the sun changes your AP will return.
 
:):)
I may be wrong but double check on couple things.

1) make sure auto-lane change is set to on in the driver assist section
2) I'm not sure if it works on non-freeway

Thanks. I had already said that I used auto lane change successfully 65% of the time - so of course that means I have turned it on. Otherwise I could not use it at all.

This is US 101 which is definitely considered a freeway here in California.

U.S. Route 101, or U.S. Highway 101 is a north–south United States Numbered Highway that runs through the states of California, Oregon, and Washington, on the West Coast of the United States -- Wikipedia

This was a more technical post trying to prompt speculation about the particulars of why AP doesn't know how many lanes a major US highway has - is it all camera issues and sun angles? What about high resolution mapping, etc.

It was also to perhaps educate some people about the fact that by looking at the binacle display and seeing if there are side lanes displayed, will tell you in advance if auto lane change will or will not work.
 
I have used auto lane change quite a bit, but only have ever attempted to use it on interstate roads, where in my experience it has worked ~ 95% of the time; the only times it didn't I thought I could see the reason, i.e., the lines on the road were not clear, or not very visible.

Is US 101 a divided, limited-access highway, like an interstate? (I'm not convinced that a Tesla "knows" whether it is on an interstate or not, due to the large amount of detail data that would have to be there to enable this - but interstate roads do have characteristics for which auto-lane keeping and change are optimized)...
 
@AB4EJ US 101 (also called "the 101" by people in SoCal) is configured differently depending on where you are. See the photo I posted where AP doesn't see the lane to my left but from the pic a human can definitely see it? That's on 101 near Buellton. Other parts of 101 have 3, 4 or 5 lanes each direction. We in California call it a freeway (though I see on this board some people don't like that term). It has no traffic controls (stop lights/signs) that I have seen.

However, I have seen this "AP can't see adjacent lanes" behavior on 101 even in this spots where it was at least 4 lanes each direction. Then a mile or two later, all of a sudden AP could "see" (and displayed in the binnacle) the adjacent lanes. Before I noticed the binnacle display showed the faint grey adjacent line outline, it seemed totally random. But what still feels random is why ⅓ of the time on the same highway (often in the same number of lane configuration) AP can't detect the same adjacent lanes it could "see" just 30-60 seconds earlier.
 
It is not based only on what autopilot shows (sees) it is based on the mapping data that autopilot uses. You can only do auto lane change if the highway is identified as "limited access" in the database. In my recent trips there it stood out to me how many roads in California transition back and forth between limited access and non-limited access!
 
On non-freeways, regardless of number of lanes, it will not work. On my daily drive through Franconia Springfield Parkway (3 lanes) lane change does not work.

Not sure how you're defining "non-freeway" but auto lane change definitely works on any divided highway. State Highway 57 between Sturgeon Bay and Green Bay, WI is a 4-lane divided highway and is not limited-access but AP1 works as advertised there. Auto lane-change works. Driving 15 mph over the posted speed limit works. It's all good.

That said, I have experienced what @CameronB describes when I'm on an interstate highway so I'll be watching to test his theory. It's puzzled me for awhile.
 
By the picture you posted, it seems like it shouldn't have a hard time figuring out what's going on. But, I've noticed that sometimes it will get confused on what color lines on the road are. For example, I've been on 2-lane (one each direction) roads where the AP reports an adjacent (opposing) lane as ready for lane change. I've even tried it (when no cars were coming, obviously) and sure enough it went in to the opposing lane. I realized that the yellow dashed lines in the middle were not "bright enough" yellow, and the camera must have been reading them as white. Just one example of the many things they have to interpret to get it right.

If you can recreate in the same segment of road each time, it might be useful to report that specific location so they can take a look at it.
 
It is not based only on what autopilot shows (sees) it is based on the mapping data that autopilot uses. You can only do auto lane change if the highway is identified as "limited access" in the database. In my recent trips there it stood out to me how many roads in California transition back and forth between limited access and non-limited access!
it's my experience that that is not correct at all, for example I drive on a 3 lane limited access like road but the AP limits my speed as if it was on a secondary type road and I can use the auto lane changer
 
I was wondering why this has happened to me a few times. Interesting part is that this has happened to me on various multi-lane open highways. I never bothered to look at the instrument cluster to see if the adjacent lanes were showing. Good info.
 
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it's only a beta

I agree. People expect too much and failed to stop, breath, and appreciate the fact where we are in the technology. Just two years ago, a lot of these are considered a Hollywood only stuff.

Now, 10 years from now and *sugar* like this still happen, then I'll have a fit. But until then. Take it for what it is and appreciate it for what it is. A huge beta that we pay to participate in for the better future of tomorrow.
 
:):)

Thanks. I had already said that I used auto lane change successfully 65% of the time - so of course that means I have turned it on. Otherwise I could not use it at all.

This is US 101 which is definitely considered a freeway here in California.

U.S. Route 101, or U.S. Highway 101 is a north–south United States Numbered Highway that runs through the states of California, Oregon, and Washington, on the West Coast of the United States -- Wikipedia

This was a more technical post trying to prompt speculation about the particulars of why AP doesn't know how many lanes a major US highway has - is it all camera issues and sun angles? What about high resolution mapping, etc.

It was also to perhaps educate some people about the fact that by looking at the binacle display and seeing if there are side lanes displayed, will tell you in advance if auto lane change will or will not work.

I don't think I've tried on the latest update, but from what I've seen there are sections of the 101 where it won't allow lane changing at all. Just south of Gilroy is a good example.
 
Not sure how you're defining "non-freeway" but auto lane change definitely works on any divided highway. State Highway 57 between Sturgeon Bay and Green Bay, WI is a 4-lane divided highway and is not limited-access but AP1 works as advertised there. Auto lane-change works. Driving 15 mph over the posted speed limit works. It's all good.

That said, I have experienced what @CameronB describes when I'm on an interstate highway so I'll be watching to test his theory. It's puzzled me for awhile.
Thank you for pointing it out out, I should have stated that lane change currently works only on National Highways annotated on US maps with below insignia as an example.
NtnlHwysign.png
 
@CameronB I tested your theory today on Interstate Highway 43 between Milwaukee and Green Bay and again on State Highway WI-57 between Green Bay and Sturgeon Bay. There are many places where my console did not "see" an adjacent lane but happily changed lanes when I signaled.

Note: I'm using AP1; I-43 is a limited-access interstate highway; and, WI-57 is a 4-lane divided state highway with crossovers every few miles.