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Does anyone else feel that at times autopilot is herky jerky (quick, sudden acceleration from stop, quick stops) while in stop and go traffic? I don't see the rhyme or reason to it, sometimes it eases into the acceleration as I would, and other times I can feel the G-force as it tries to zoom ahead in <10 mph traffic, only to then abruptly stop as it gets closer to the vehicle ahead.

Is this an older issue that hasn't been fixed? Anyone notice any rhyme or reason to it, or any way to explain why it might happen?

M3 SR+, 2022.4.5
 
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I have mine set higher. The only difference is that it never has any quick or sudden acceleration - I find myself prodding it along with the accelerator myself just to keep in range of the car in front of me and not have 10 car lengths in there.

Stopping is also something I can't understand. You can be cruising along at 65 MPH well behind the next car (like 20 car lengths because you're at MAX cruise speed but traffic overall is faster) then see traffic stopping ahead of you on the highway. The normal reaction to seeing brake lights is to release some pressure from the accelerator and start to slow down maybe even enough to flash the brakes to the guy coming up behind you. Autopilot? LOL. The best idea from the autopilot is to cruise up at MAX speed into the stopped traffic suddenly applying enough brakes to stop in time for you, but the poor people behind you may rear-end you if they weren't really paying attention.

I was hoping that the vision-based system could see brake lights much like it can see red light cameras but apparently not (yet).

This is the first cruise control system where I have to keep my foot near the accelerator and not the brake because it can't keep up with traffic when I need it to, and it tries to stop whenever I'm about to overtake a truck in the lane next to mine and I really don't want to stop for shadows on the highway. I get a lot of weird looks from the other drivers. Good thing my windows are tinted.
 
Stopping is also something I can't understand. You can be cruising along at 65 MPH well behind the next car (like 20 car lengths because you're at MAX cruise speed but traffic overall is faster) then see traffic stopping ahead of you on the highway. The normal reaction to seeing brake lights is to release some pressure from the accelerator and start to slow down maybe even enough to flash the brakes to the guy coming up behind you. Autopilot? LOL. The best idea from the autopilot is to cruise up at MAX speed into the stopped traffic suddenly applying enough brakes to stop in time for you, but the poor people behind you may rear-end you if they weren't really paying attention.
I tried the traffic aware cruise control (TACC) a few times. This is the first car that I have had with adaptive cruise control.

When using TACC, its behavior when approaching slower traffic ahead is (annoyingly) just like you describe above. It keeps going at the set speed and then quickly slows down when reaching the set following distance, rather than gradually slowing down to end up matching the speed when reaching the set following distance.

Assuming that Autopilot is a superset of TACC and FSDB is a superset of Autopilot, it does not seem like they are anywhere near ready to even be called "beta" if TACC acts like this. Good thing TACC, Autopilot, and FSDB were not reasons for buying the car for me.
 
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I had the same issue yesterday in stop and go traffic. It would rapidly accelerate and then slam the brake every time the car in front of me would inch forward. I had my following distance set to 3.
I tried Chill in the FSD Beta settings but that didn't make a difference. It was so bad that my passengers complained and I had to drive manually in bumper to bumper for 3 hours. Normally in bumper to bumper it's pretty smooth and nobody could tell that I wasn't driving. I even tried TACC but it had the same hard acceleration and braking behavior.
 
the acceleration from a stop is probably my biggest complaint with autopilot... my best guess is that its doing multiple things...

it probably has a subroutine for dealing with stop and go traffic so that first bit of acceleration, up to around 20mph, is quicker, after you breach that speed and the car in front continues forward, again my guess, is that more safety routines kick in as higher speeds are reached making the car want to lag behind the car in front of you a bit so that it can get a proper view of the lane lines as well as providing a good distance buffer. and then on top of that the general acceleration from a stop is a bit slower than a person would do.

all of that combined makes it just not want to get up to speed like a human would, while you can compensate for that by using the accelerator i do hope future updates make this process a little smoother.

same thing with the stopping, i'm assuming there are multiple systems at work all with different priorities... one is trying to make sure you dont hit the car in front of you, another is trying to make sure the car is actually stopping and not just slowing down, another is evaluating traffic around you looking for patterns that might cause a deviation in your course, etc...

thankfully we own tesla's and unlike other cars we will see improvement over time
 
I had the same issue yesterday in stop and go traffic. It would rapidly accelerate and then slam the brake every time the car in front of me would inch forward. I had my following distance set to 3.
I tried Chill in the FSD Beta settings but that didn't make a difference. It was so bad that my passengers complained and I had to drive manually in bumper to bumper for 3 hours. Normally in bumper to bumper it's pretty smooth and nobody could tell that I wasn't driving. I even tried TACC but it had the same hard acceleration and braking behavior.
I had almost an identical experience yesterday. I think it got worse work a recent update.
 
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I had the same issue yesterday in stop and go traffic. It would rapidly accelerate and then slam the brake every time the car in front of me would inch forward. I had my following distance set to 3.
I tried Chill in the FSD Beta settings but that didn't make a difference. It was so bad that my passengers complained and I had to drive manually in bumper to bumper for 3 hours. Normally in bumper to bumper it's pretty smooth and nobody could tell that I wasn't driving. I even tried TACC but it had the same hard acceleration and braking behavior.
I also had the same experience yesterday. I don’t recall it being that bad in the past.
 
the acceleration from a stop is probably my biggest complaint with autopilot... my best guess is that its doing multiple things...

it probably has a subroutine for dealing with stop and go traffic so that first bit of acceleration, up to around 20mph, is quicker, after you breach that speed and the car in front continues forward, again my guess, is that more safety routines kick in as higher speeds are reached making the car want to lag behind the car in front of you a bit so that it can get a proper view of the lane lines as well as providing a good distance buffer. and then on top of that the general acceleration from a stop is a bit slower than a person would do.

all of that combined makes it just not want to get up to speed like a human would, while you can compensate for that by using the accelerator i do hope future updates make this process a little smoother.

same thing with the stopping, i'm assuming there are multiple systems at work all with different priorities... one is trying to make sure you dont hit the car in front of you, another is trying to make sure the car is actually stopping and not just slowing down, another is evaluating traffic around you looking for patterns that might cause a deviation in your course, etc...

thankfully we own tesla's and unlike other cars we will see improvement over time
They had this major problem, which makes AP unusable to many, "Solved" until about two years ago. I would agree that since even level five autonomy is useless unless this is addressed, and therefore the entire software team would be best deployed in fixing AP extreme acceleration and then last-minute brake slamming as if to avoid the accident AP almost created. However, it's not a technological hurdle like level five autonomy, it is an intentional choice (it was "solved" before it became an issue). Therefore unless Tesla chooses to stop this, or at least add a motion sickness or carsick mode, AP could simply be unusable to a significant number of drivers indefinitely. Also, I brought this exact issue up on Thursday but a fraction of the people responded. I'm just wondering why? I'm new at forums. 2022.4.5 promises non vomit inducing AP stop and go driving in the release notes. But it seems the same to me, am I missing something?
 
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Does anyone else feel that at times autopilot is herky jerky (quick, sudden acceleration from stop, quick stops) while in stop and go traffic? I don't see the rhyme or reason to it, sometimes it eases into the acceleration as I would, and other times I can feel the G-force as it tries to zoom ahead in <10 mph traffic, only to then abruptly stop as it gets closer to the vehicle ahead.

Is this an older issue that hasn't been fixed? Anyone notice any rhyme or reason to it, or any way to explain why it might happen?

M3 SR+, 2022.4.5
yes noticed it today during a train strike, felt really sick, chande somw settings and it improved a little, went from hold to roll, changed acceleration to chill, still had issues around the 8kph (5mph)
 
Someone mentioned a possible solution in the thread about this issue that I started before this thread that fewer people commented in.

[B][SIZE=3]Huskyf[/SIZE][/B] sugested lowering the top AP speed in stop and go. On the freeway AP is automatically set to full freeway speed based on the allowable speed limit, but perhaps if I set it to 5mph that would do it. I will experiment with this.


I work at home and don't drive that often but the prospect of using AP in traffic (the situation in which I would get by the far the most value from it, and also the situation I've been unable to use it for the past two years) is very exciting. I will report back.

The only snag I expect from this workaround is that limiting the speed low enough to avoid vomit-inducing jumping and then break slamming will create a lot of road rage and honking (since AP will not be able to comfortably catch up with traffic if it accelerated beyond the 5mph for a bit, like if traffic went to 10mph for a few minutes AP would still go 5mph). I guess you could constantly manually catch up, or just chill and deal with the rage. At least newer modals have acoustic glass to help with the honking a bit. I really think the best solution is to have the cameras see stop and go traffic (Like our eyes do) or even without cameras, if the computer senses a complete stop, then moving a few feet before another complete stop, and then moving a few feet, over and over, then it's obviously stop and go traffic, the blind computer that senses speed should be able to know that it's in stop and go traffic. Then when the computer knows it's stop and go traffic smoothing out acceleration and breaking. This workaround could work though, if Tesla doesn't want to do the better solution that would be able to adjust to the ideal traffic speed though.
 
Someone mentioned a possible solution in the thread about this issue that I started before this thread that fewer people commented in.

[B][SIZE=3]Huskyf[/SIZE][/B] sugested lowering the top AP speed in stop and go. On the freeway AP is automatically set to full freeway speed based on the allowable speed limit, but perhaps if I set it to 5mph that would do it. I will experiment with this.


I work at home and don't drive that often but the prospect of using AP in traffic (the situation in which I would get by the far the most value from it, and also the situation I've been unable to use it for the past two years) is very exciting. I will report back.

The only snag I expect from this workaround is that limiting the speed low enough to avoid vomit-inducing jumping and then break slamming will create a lot of road rage and honking (since AP will not be able to comfortably catch up with traffic if it accelerated beyond the 5mph for a bit, like if traffic went to 10mph for a few minutes AP would still go 5mph). I guess you could constantly manually catch up, or just chill and deal with the rage. At least newer modals have acoustic glass to help with the honking a bit. I really think the best solution is to have the cameras see stop and go traffic (Like our eyes do) or even without cameras, if the computer senses a complete stop, then moving a few feet before another complete stop, and then moving a few feet, over and over, then it's obviously stop and go traffic, the blind computer that senses speed should be able to know that it's in stop and go traffic. Then when the computer knows it's stop and go traffic smoothing out acceleration and breaking. This workaround could work though, if Tesla doesn't want to do the better solution that would be able to adjust to the ideal traffic speed though.
I think your overthinking it before trying. (fear of honk). If 5mph is to slow try 10 or 20 0r …. Just don’t use 70mph in traffic.