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Autopilot dangerously reducing speed on highways

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I agree with @Knightshade, we drive on Hwy 290 in Houston where it had been under major renovation for about 7 years. It's pretty much done, about 3 years behind schedule, the two biggest issue I have with the renovation is 1) striping is not complete and 2) speeds are not updated for Tesla usage. The speed signs appear to be correct but the database that Tesla uses is not. Same portion of the hwy will go from 65mph to 45mph. 45 was the construction speed years ago, it is annoying and dangerous.

I drive on 290 all the time. The cause of this is indeed a mapping error, but it's not because the speed limits for the freeway are incorrect in the database. The construction speed limits of 45 MPH are not and were never in the database. The cause is that the construction has widened the entire freeway such that it now crosses places where the old frontage road was, where the speed limit was 45 MPH. When your car travels on the new lanes that go into a GPS location that used to be the frontage road, the Tesla drops the speed limit to 45 MPH. If you cruise down the freeway in the left lane, this will either never happen or will happen only once. Do the same thing down the right lane and it will happen repeatedly because you're overlapping the old frontage road a lot more often.

This, to me, illustrates one of the long-term problems with the idea of FSD: Without a perfectly accurate and fully updated map, FSD has no hope. It doesn't matter how good the FSD algorithms end up being -- if the car doesn't know where it is then it is fundamentally impossible for it to drive on its own. 290 has been widened for the most part with final construction in the finishing stages for nearly 2 years, and Tesla's maps are still not updated. For FSD to work, they will need map updates on the order of hours, not years. That's a 5-order-of-magnitude improvement required. Good luck with that.
 
This, to me, illustrates one of the long-term problems with the idea of FSD: Without a perfectly accurate and fully updated map, FSD has no hope.

Sure it does.

Read the speed limit signs and use those.

AP1 did it. Only reason AP2 didn't is mobileye holds the patent on doing that.

FSD will eventually need to either license it or use some method that doesn't infringe on their patent.
 
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If I remember correctly Elon said that they are not relying on GPS data (HD GPS) but teaching the car to see and respond to the posted speed limit signs. This was the differentiating factor according to him between wamo (Lidar, GPS, geofence) and FSD (vision and ML). So I guess if you bought FSD you should not have "phantom braking" problems?
 
If I remember correctly Elon said that they are not relying on GPS data (HD GPS) but teaching the car to see and respond to the posted speed limit signs. This was the differentiating factor according to him between wamo (Lidar, GPS, geofence) and FSD (vision and ML). So I guess if you bought FSD you should not have "phantom braking" problems?


AP2+ absolutely does not use speed limit sign reading to determine speed of the vehicle right now. it uses map/GPS data, regardless of if you paid for FSD or not.
 
AP2+ absolutely does not use speed limit sign reading to determine speed of the vehicle right now. it uses map/GPS data, regardless of if you paid for FSD or not.

That is very interesting because on the analyst call Elon shot down the use of HD GPS, and mapping data in favor of vision and ML.. unless he is talking about what is to come with FSD in the future .. Just curious what happens when you are in a tunnel (no GPS) ? What happens when you are in a tunnel with a road above it with speed limit of 45mph and a tunnel speed limit of 60mph ?
 
HD mapping is things like Caddy is doing where they high-res lidar map every inch of the road. (which is why Supercruise works on only like 10% of the roads Autopilot does- they lack maps everywhere else)

That's vastly different than "generic GPS signal tells car which road you're on, and cross-references to a speed limit database"

If you lose GPS for a minute in a tunnel that's no issue with the 2nd thing, since it knows where you were entering the tunnel and it knows your direction and speed while IN the tunnel
 
On a 4-lane interstate there is a section where if I am in the 2 right lines my speed will go from 70mph to 55 or even down to 35 if I am in the far right lane!! Full regen kicks in. Not fun!

So, not a bug. Its part of the FSD in the wild fantasy.

They really need an option how all the other cruise controls work. You set a speed to maintain and that's it. TACC can make the car slow down if a car is in front. Good-by phantom breaking due to incorrect speed maps.
 
It has to be the cameras causing this. I was in stop and go traffic yesterday going 5 mph and it braked unexpectedly several times. Each time I noticed phantom cars on the display in my lane as well as the ones next to me over the lane line. It appears to me the camera thinks the car is in danger of being hit. I have had it happen at speed as well, but wasn’t looking at the screen at the time. It’s a shame, like others have said that we don’t have a TACC mode that just uses the front sensors.
 
On a 4-lane interstate there is a section where if I am in the 2 right lines my speed will go from 70mph to 55 or even down to 35 if I am in the far right lane!! Full regen kicks in. Not fun!

So, not a bug. Its part of the FSD in the wild fantasy.

They really need an option how all the other cruise controls work. You set a speed to maintain and that's it. TACC can make the car slow down if a car is in front. Good-by phantom breaking due to incorrect speed maps.

I am having a similar experience. I have sections of the interstate where no construction has occurred in years and if I am in the right lane it clearly assumes I am taking an exit ramp and starts slowing. I almost got rear-ended yesterday by someone who was taking the exit ramp and planning on passing me on the right assuming I was going to keep a constant speed. I could see them make a quick correction to the right and then the obligatory finger and honk as they exited. I would have been pissed too.

I turn off TACC and AP in areas where there was construction in the past year or so because I can't trust it and I don't like surprises driving at highway speeds. TACC behavior is my biggest disappointment in the car.
 
Same thing in Temple TX. Once the road construction was done Tesla tried to correct the problem by removing the speed limit, then we got the new update and now at the end of the patch where the speed limit was removed it showed up at 45 mph. Mind you this is a 70 mph zone and most drive 75 to 80. So 75 to 45 is jarring and dangerous.
Still not fixed. Just happened to us again!
 
Tesla has been using cameras to recognize posted speed limit signs for at least a year now. I’ve seen the car catch construction temporary speed limit signs (orange) and change the speed limit accordingly. It doesn’t always get it or see it, especially if occluded, but it does seem to see it. I don’t know if they’ve licensed the patent or found a way around it, but it is clear Tesla is reconciling mapping data and live camera feeds, just like FSD beta does when trying to navigate newly constructed roads (or newly blocked off). Again, it’s not perfect at it, and in some areas it’s pretty bad. But when it does work, it works pretty well.

I found the release notes for 2020.36.x that announced cameras recognizing speed limit signs. It’s in some later versions’ release notes as well (e.g. - 2020.40.x), but not sure if it’s any earlier than this one: 2020.36 Official Tesla Release Notes - Software Updates