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While I don't know how good Tesla's self-driving is, I do have experience with a limited keep-your-lane system in a BMW. The one that actually steers. It requi

While I don't know how good Tesla's self-driving is, I do have experience with a limited keep-your-lane system in a BMW. The one that actually steers. It requires a lot of force to override it. And remember, it requires you to keep the hands on the wheel. But you are not expecting to have to fight it, so there are some delays there. Then you're fighting a system that you don't know how much force it takes to override it. You don't want to apply too much force because you might be barreling down the freeway at 80mph. At those speeds you just nudge the steering wheel. But that's not the case when you need to override the car. And it happens more then you expect. Every time the car mis-calculates the actual lines on the road it'll do it. Changes in paint where the old one is still there for example. Or just faded paint and all of the sudden it detects a diagonally going split between 2 slabs of concrete as the lane separator. Or you're doing 50mph, and you're passing a couple of cyclists. If you don't turn on your turn signal and you weave to the left to pass them the car will literally steer back into the direction of the cyclists. Scary.

trbleclef 3y ago
This all feels very MCAS to me.
- nickpinkston 3y ago
  I drove one of these BMWs too and had the same thought. It seems like too far in the other direction.
- jlkuester7 3y ago
  Yes this is it! I was trying to describe my misgivings with this functionality and this is exactly it. You have a powerful system with a ton of edge cases where the penalty for getting a minor edge case wrong is that someone(s) dies.
- KennyBlanken 3y ago
  No? MCAS was necessary because Boeing made the plane aerodynamically unstable. They did so because of pressure to compete against superior Airbus offerings, and because a new airframe (the proper solution) would have been a huge undertaking and airlines wouldn't like it because they'd have to get pilots certified on the new airframe. Boeing then did not implement sufficient redundancy in the system, proper warning annunciators, training, documentation, etc. Many pilots had no idea the system existed. There are similarities, however. A large part of the reason Tesla has so many problems is because Musk decreed that radar was too expensive and discontinued installing them, forcing the system to rely on stereo camera vision. Even worse: Tesla disabled the radar systems in older cars because they didn't want the older cars to be more capable - it would be a very inconvenient way for the public, press, and regulators to see how deficient the camera-only approach was.
  - ericd 3y ago
    Not sure why you’re talking about the deficiencies of the model sans radar throughout the thread, I haven’t noticed any degradation - on the contrary, the performance is better now than when the car was new a few years back. Do you have a statistically backed source for this, or is this based on media/hearsay?
  - tzs 3y ago
    > MCAS was necessary because Boeing made the plane aerodynamically unstable It's not aerodynamically unstable. MCAS was required because in certain parts of the flight envelope outside of normal operation the pull-force feel of the control column was lighter than during normal operation. The FAA regulations require it to be heavier.
rootusrootus 3y ago
I think that's fairly common amongst lane centering implementations. One thing I think is unique about Tesla's autopilot is that if you grab the wheel and override the steering, it disengages AP altogether. That is, including the traffic-aware cruise control. I believe most/all other manufacturers maintain speed unless you also hit the brakes.
- netvl 3y ago
  It does not - my M3 continues to keep the speed if I override autopilot with the steering wheel. If I press the brakes, then both systems are shut down.
WesolyKubeczek 3y ago
> If you don't turn on your turn signal and you weave to the left to pass them ...oh nice, the car scares you into remembering that you should always signal passing maneuver with your blinker! Another case where this system goes awry: in light drizzle, cars leave wet trails behind that shine and this system will mistake them for lane markings. I have to turn LTA off in such condition or it would steer me right off the road!
- cnity 3y ago
  There are a lot of cases where you pass a line without indicating though. There are also a lot of cases where a line ease off to the side in a turn-off that would guide the lane assisted vehicle off the road. Just do a google search for these kinds of cases. This technology is immature and dangerously fails in a lot of cases already.
  - WesolyKubeczek 3y ago
    Wait wait. You are passing cyclists. Blinking serves two purposes: you are letting them know that you have noticed them (so they know you're not just going to plow right through them) and you are letting them know you are going to pass them (so they don't do stupid shit like decide to turn left at exactly this moment). If a car behind me, in the same lane, was passing me without blinking, I would highly suspect a drunk or overtired driver.
    - cnity 3y ago
      My comment was a bit misleading, sorry. I do indicate when passing cyclists. I read your comment as suggesting that the assumption lane assist makes is OK because one should always indicate when crossing a lane marking (which is not always the case).
    - soco 3y ago
      I'm not sure how can a cyclist see your blinker - you are behind them when starting to overtake and looking back is not something cyclists do much (or more than once)...
robertlagrant 3y ago
> you're passing a couple of cyclists. If you don't turn on your turn signal and you weave to the left to pass them This is why everyone gives me evil looks when I drive my own BMW :)
ec109685 3y ago
Teslas don’t require much force at all to disengage.
- azinman2 3y ago
  I don’t know what BMW is like but it requires more force than I think is safe.
  - soco 3y ago
    My 10yo VW only nudges you gently, no force required to steer it your way. Even that nudge is annoying to some, but it's definitely not dangerous.
- tshaddox 3y ago
  I have a 2020 Subaru that requires very little force to move the steering wheel when lane centering is engaged. My Tesla Model 3 requires a bit more force, but it's still quite light.
  - cchance 3y ago
    I mean barely any, but also you can tap break, or hit the stalk, like theirs a billion ways to disable, a crash if FSD is enabled actually, was because the driver didn't even try to stop it.
- bombcar 3y ago
  The Kia lane following, if anything, is a bit too weak (it follows more lazily than I would) but it certainly doesn't require any major force to overcome it - and most important - it does NOT disengage if you nudge it back to the right place, it just accepts the new normal and keeps going. Similarly it's smart enough to NOT disengage cruise control if you hit the gas, but will if you tap the brakes (which you don't often need to do because the space management works decently well). Ten years ago I would feel pretty comfortable driving any vehicle (up to and including double-shifted manual transmission military trucks). Now I feel each new car needs a separate training regiment because all the automated systems operate so differently from each other.
kristjansson 3y ago
> If you don't turn on your turn signal ... the car will literally steer back This kills me about BMW's lane-keep system. It doesn't just lane-keep in the absence of input, it actively fights driver input that would take it over the lane lines.
- NoPedantsThanks 3y ago
  [dead]
- cchance 3y ago
  Ya no tesla disables by tapping break at all, or even twitching the steering wheel, If this was in fact a FSD crash, the driver didn't try to stop it in any way.
- brewdad 3y ago
  To be fair, that is the point of lane-keep assist. To keep an inattentive driver from drifting out of their lane. Without any input to the contrary, it should assume a car leaving its lane is unintentional and try to correct it. That what it is designed to do. My Volvo has an early version of lane-keep assist (2017 model first introduced in 2015). It will fight me when it thinks I'm out of a lane. Fortunately, it doesn't take much input force to override it. It is still strong enough initially that if I were driving without holding the steering wheel appropriately it would cause a problem. Also, I must remember to turn it off if there is any snow or ice on the road surface as that tends to put the car in "kill me mode".
  - pavel_lishin 3y ago
    > To be fair, that is the point of lane-keep assist. To keep an inattentive driver from drifting out of their lane. Without any input to the contrary, it should assume a car leaving its lane is unintentional and try to correct it. That what it is designed to do. But the whole point was that the driver explicitly turned the wheel in order to partially leave their lane, in order to give bicyclists space. They weren't drifting - they were actively steering.
cnity 3y ago
I have actually been in a car crash that was caused by the lane-assist feature in the Rivian R1S. It misread the proximity of the concrete K-rails on each side and jerked the steering wheel into the wrong lane. The correction of the driver to avoid (dangerously) switching lanes kicked the back of the car out at 75mph and we drifted, hitting one rail, bouncing off and hitting the other. It was a violent enough collision to write off the car, but fortunately the construction of the vehicle saved us and nobody had any particularly severe injuries. I now am adamant about drivers not experimenting with those features while I am in the car because I don't trust them.
jeffbee 3y ago
If you are passing cyclists at 50 MPH you should be an entire lane to their left.
pavel_lishin 3y ago
> And it happens more then you expect. Every time the car mis-calculates the actual lines on the road it'll do it. Changes in paint where the old one is still there for example. Or just faded paint and all of the sudden it detects a diagonally going split between 2 slabs of concrete as the lane separator. Our Subaru came with "lane assist" enabled by default, and I turned it off in under a week after it kept trying to "assist" me on New Jersey's highways right across a lane of traffic in construction zones.
ericd 3y ago
It takes very little force to disengage in the Tesla, at least when it works properly (I haven’t had it work improperly, but I could imagine a bug that prevented it from detecting that causing issues).

trbleclef 3y ago

This all feels very MCAS to me.

nickpinkston 3y ago
I drove one of these BMWs too and had the same thought. It seems like too far in the other direction.
jlkuester7 3y ago
Yes this is it! I was trying to describe my misgivings with this functionality and this is exactly it. You have a powerful system with a ton of edge cases where the penalty for getting a minor edge case wrong is that someone(s) dies.
KennyBlanken 3y ago
No? MCAS was necessary because Boeing made the plane aerodynamically unstable. They did so because of pressure to compete against superior Airbus offerings, and because a new airframe (the proper solution) would have been a huge undertaking and airlines wouldn't like it because they'd have to get pilots certified on the new airframe. Boeing then did not implement sufficient redundancy in the system, proper warning annunciators, training, documentation, etc. Many pilots had no idea the system existed. There are similarities, however. A large part of the reason Tesla has so many problems is because Musk decreed that radar was too expensive and discontinued installing them, forcing the system to rely on stereo camera vision. Even worse: Tesla disabled the radar systems in older cars because they didn't want the older cars to be more capable - it would be a very inconvenient way for the public, press, and regulators to see how deficient the camera-only approach was.
- ericd 3y ago
  Not sure why you’re talking about the deficiencies of the model sans radar throughout the thread, I haven’t noticed any degradation - on the contrary, the performance is better now than when the car was new a few years back. Do you have a statistically backed source for this, or is this based on media/hearsay?
- tzs 3y ago
  > MCAS was necessary because Boeing made the plane aerodynamically unstable It's not aerodynamically unstable. MCAS was required because in certain parts of the flight envelope outside of normal operation the pull-force feel of the control column was lighter than during normal operation. The FAA regulations require it to be heavier.

rootusrootus 3y ago

I think that's fairly common amongst lane centering implementations. One thing I think is unique about Tesla's autopilot is that if you grab the wheel and override the steering, it disengages AP altogether. That is, including the traffic-aware cruise control. I believe most/all other manufacturers maintain speed unless you also hit the brakes.

netvl 3y ago
It does not - my M3 continues to keep the speed if I override autopilot with the steering wheel. If I press the brakes, then both systems are shut down.

WesolyKubeczek 3y ago

> If you don't turn on your turn signal and you weave to the left to pass them ...oh nice, the car scares you into remembering that you should always signal passing maneuver with your blinker! Another case where this system goes awry: in light drizzle, cars leave wet trails behind that shine and this system will mistake them for lane markings. I have to turn LTA off in such condition or it would steer me right off the road!

cnity 3y ago
There are a lot of cases where you pass a line without indicating though. There are also a lot of cases where a line ease off to the side in a turn-off that would guide the lane assisted vehicle off the road. Just do a google search for these kinds of cases. This technology is immature and dangerously fails in a lot of cases already.
- WesolyKubeczek 3y ago
  Wait wait. You are passing cyclists. Blinking serves two purposes: you are letting them know that you have noticed them (so they know you're not just going to plow right through them) and you are letting them know you are going to pass them (so they don't do stupid shit like decide to turn left at exactly this moment). If a car behind me, in the same lane, was passing me without blinking, I would highly suspect a drunk or overtired driver.
  - cnity 3y ago
    My comment was a bit misleading, sorry. I do indicate when passing cyclists. I read your comment as suggesting that the assumption lane assist makes is OK because one should always indicate when crossing a lane marking (which is not always the case).
  - soco 3y ago
    I'm not sure how can a cyclist see your blinker - you are behind them when starting to overtake and looking back is not something cyclists do much (or more than once)...

robertlagrant 3y ago

> you're passing a couple of cyclists. If you don't turn on your turn signal and you weave to the left to pass them This is why everyone gives me evil looks when I drive my own BMW :)

ec109685 3y ago

Teslas don’t require much force at all to disengage.

azinman2 3y ago
I don’t know what BMW is like but it requires more force than I think is safe.
- soco 3y ago
  My 10yo VW only nudges you gently, no force required to steer it your way. Even that nudge is annoying to some, but it's definitely not dangerous.
tshaddox 3y ago
I have a 2020 Subaru that requires very little force to move the steering wheel when lane centering is engaged. My Tesla Model 3 requires a bit more force, but it's still quite light.
- cchance 3y ago
  I mean barely any, but also you can tap break, or hit the stalk, like theirs a billion ways to disable, a crash if FSD is enabled actually, was because the driver didn't even try to stop it.
bombcar 3y ago
The Kia lane following, if anything, is a bit too weak (it follows more lazily than I would) but it certainly doesn't require any major force to overcome it - and most important - it does NOT disengage if you nudge it back to the right place, it just accepts the new normal and keeps going. Similarly it's smart enough to NOT disengage cruise control if you hit the gas, but will if you tap the brakes (which you don't often need to do because the space management works decently well). Ten years ago I would feel pretty comfortable driving any vehicle (up to and including double-shifted manual transmission military trucks). Now I feel each new car needs a separate training regiment because all the automated systems operate so differently from each other.

kristjansson 3y ago

> If you don't turn on your turn signal ... the car will literally steer back This kills me about BMW's lane-keep system. It doesn't just lane-keep in the absence of input, it actively fights driver input that would take it over the lane lines.

NoPedantsThanks 3y ago
[dead]
cchance 3y ago
Ya no tesla disables by tapping break at all, or even twitching the steering wheel, If this was in fact a FSD crash, the driver didn't try to stop it in any way.
brewdad 3y ago
To be fair, that is the point of lane-keep assist. To keep an inattentive driver from drifting out of their lane. Without any input to the contrary, it should assume a car leaving its lane is unintentional and try to correct it. That what it is designed to do. My Volvo has an early version of lane-keep assist (2017 model first introduced in 2015). It will fight me when it thinks I'm out of a lane. Fortunately, it doesn't take much input force to override it. It is still strong enough initially that if I were driving without holding the steering wheel appropriately it would cause a problem. Also, I must remember to turn it off if there is any snow or ice on the road surface as that tends to put the car in "kill me mode".
- pavel_lishin 3y ago
  > To be fair, that is the point of lane-keep assist. To keep an inattentive driver from drifting out of their lane. Without any input to the contrary, it should assume a car leaving its lane is unintentional and try to correct it. That what it is designed to do. But the whole point was that the driver explicitly turned the wheel in order to partially leave their lane, in order to give bicyclists space. They weren't drifting - they were actively steering.

cnity 3y ago

I have actually been in a car crash that was caused by the lane-assist feature in the Rivian R1S. It misread the proximity of the concrete K-rails on each side and jerked the steering wheel into the wrong lane. The correction of the driver to avoid (dangerously) switching lanes kicked the back of the car out at 75mph and we drifted, hitting one rail, bouncing off and hitting the other. It was a violent enough collision to write off the car, but fortunately the construction of the vehicle saved us and nobody had any particularly severe injuries. I now am adamant about drivers not experimenting with those features while I am in the car because I don't trust them.

jeffbee 3y ago

If you are passing cyclists at 50 MPH you should be an entire lane to their left.

pavel_lishin 3y ago

> And it happens more then you expect. Every time the car mis-calculates the actual lines on the road it'll do it. Changes in paint where the old one is still there for example. Or just faded paint and all of the sudden it detects a diagonally going split between 2 slabs of concrete as the lane separator. Our Subaru came with "lane assist" enabled by default, and I turned it off in under a week after it kept trying to "assist" me on New Jersey's highways right across a lane of traffic in construction zones.

ericd 3y ago

It takes very little force to disengage in the Tesla, at least when it works properly (I haven’t had it work improperly, but I could imagine a bug that prevented it from detecting that causing issues).