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AP - 45mph default in 7.1 is potentially dangerous

Discussion in 'Model S' started by thegruf, Jan 23, 2016.

  1. thegruf

    thegruf Member

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    well it is to me at least.

    A drive this afternoon; on the way out the car sits quite happily at 65mph on a 60mph road on AP all the way.

    The return journey however the car decides it doesnt know the speed limit at one point and slows the car to 45mph.

    Not a big deal?

    Well tell that to the poor chap who was behing the car following me, when my car slows suddenly without any brake lights in the middle of a series of sweeping curves, causing the car behing me to over-react to this completely unexpected and unreasonable event (no brake lights but noticeable deceleration as the AP gently but firmly reduced speed in the middle of a curve ffs), the car behind him then has to panic brake and slides out sideways into the oncoming traffic. How the hell there wasnt a sizeable accident can only be down to sheer luck. To say the chap was (entirely understandably) pissed when he came past me later would be an understatement.

    The righteous here will undoubtedly chime in about how you shouldn't follow too close, which I will pre-empt by saying that to my opinion everyone was driving entirely sensibly.
    But abruptly slowing down in the middle of a curve without warning is inviting trouble.

    Sorry Tesla, I understand why you felt the need to introduce it, but this is a dumb feature that you have to improve the implementation of, and quickly before it causes accidents.
     
  2. msnow

    msnow Active Member

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    I don't understand why you didn't just turn AP off when you sensed that. Wouldn't that have solved the problem?
     
  3. kort677

    kort677 Active Member

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    the quick solution is to move right foot onto the accelerator pedal and apply enough force to the peddle with your leg/foot to cause the car to maintain your preferred speed whenever the AP gets confused about what the speed limit is. I hope this assists you on your journeys. remember it's a BETA.
     
  4. thegruf

    thegruf Member

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    i did, but as there is no warning in the car and it behaved perfectly on the same road I was not anticipating a problem, so my reaction time was slow, by the time I had accelerated (not switched off AP) the reactions behind had already occurred.

    I am sure there are saints here who could have done better.

    I understand it is beta - this aspect needs to be improved
     
  5. msnow

    msnow Active Member

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    Understood. I'm no "saint" either and I'm pretty sensitive to cars riding my tail.
     
  6. Caligula

    Caligula Member

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    My DS stated that AP "should only be used in situations where you'd be comfortable using standard cruise control". Given that I probably wouldn't be using cruise control in a situation like this, I'm going to say that this is probably good advice? Perhaps I'm reading the road/conditions incorrectly in the OP, but I'd typically not use cruise control when driving through "a series of sweeping curves".
     
  7. jerjozwik

    jerjozwik Member

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    #7 jerjozwik, Jan 23, 2016
    Last edited: Jan 23, 2016
    someone else fails to react and/or was following too close through blind corners and AP is to blame?
     
  8. deonb

    deonb Active Member

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    We have generations of people of people who are on the road and used to cars in front of them to behave in a rational and predictable way. If you know the road and you know what the car 2 ahead of you is doing you can predict what the car directly ahead of you will be doing as well. That is how we can have safe follow distances that's less than the stopping distance of a vehicle.

    It will take time for people to unlearn that and start to accommodate traffic patterns where other cars on the road can behave in a spontaneous and surprising way with no predictable rhyme or reason behind their actions.

    Computers are good at that, and humans trained in that is good at it. But not everybody on the road is trained at that yet.
     
  9. thegruf

    thegruf Member

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    clearly you are commenting on a different scenario to the one that I posted.

    Open road, wide sweeping curves with good unrestricted visibility, cars following sensibly, good marking my vehicle had previously negotiated this road in the other direction without any issue whatsoever.
    What nobody should reasonably expect is the car to slow without warning (no brake lights) in the middle of a curve.

    In a sterile. theoretical environment everyone can stop if the car in front suddenly halts. I don't question that.
    Reality is that this is invariably compromised in the real world.

    There was no reason for the other drivers to expect my car to slow suddenly in the way that it did.

    Tesla have put this mode in 7.1 that did not exist in 7.0.
    Undoubtedly this is to reduce risk in other scenarios.
    I contend that in doing so they have introduced a significant new risk.

    All this requires is some simple modification(s) to mitigate the risk.
     
  10. Caligula

    Caligula Member

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    FWIW, I typically use engine braking in my manual transmission ICE vehicle when slowing down in curves. Vehicles slowing during cornering (without brake lights) isn't something that's isolated to cars with AP.

    Also regarding my previous reply about using AP where one would use cruise control:

    "Using cruise control on a winding or twisty road can be a problem because you could find yourself going too fast as you approach a curve in the road."

    Maine BGS: Risk Management - Tips of the Month from the Past - Cruise Control Driving

    Sounds familiar?

    I should note that this is probably the most liberal rule of thumb I've found, by the way. Most places outright state that you should never use CC on curving or twisty roads.

    Of course, again, I may be reading the conditions wrong in the OP... but this seems relevant given the instructions my DS gave me
     
  11. pdq

    pdq Member

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    I agree with thegruf. There are so many other aspects of the car that need immediate improvement, why is Tesla wasting their time on stuff like this. Who at Tesla took it upon themselves to decide that owners should never drive more than 5MPH over the posted speed limit on undivided roads? Let me know, and I'll buy them a custom cap with "Big Brother" on it. I like AP, but if I'm limited to the posted speed +5, I'll have cars stacked up like cord wood where I live.
     
  12. msnow

    msnow Active Member

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    It was in response to regulators. I'll take a size 7 1/2 hat. Thanks.
     
  13. kort677

    kort677 Active Member

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    as previously noted there is a simple fix for your complaint, take right foot, place it on the accelerator, apply correct amount of pressure to attain and hold whatever speed you care to drive at.
     
  14. Cyberax

    Cyberax Member

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    Oh wow! Turns out that my Chevy Volt also has an autopilot! It just requires periodic torque application to the steering wheel.
     
  15. S4WRXTTCS

    S4WRXTTCS Active Member

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    #15 S4WRXTTCS, Jan 23, 2016
    Last edited: Jan 23, 2016
    There are two aspects that I greatly dislike about AP in V7.1.

    The first is the +5MPH over limit on undivided roads. Now I don't think this was a bad idea in itself, but the problem is the car doesn't always correctly identify a road or the speed limit. Sometimes it's because of the massively outdated maps and sometimes the MobileEye system flatly reads the speed limits incorrectly. I wouldn't have a problem with if it only impacted engagement. But, my understanding is if it detects that you switched road-types/speed-limits it will slow down and that may have been what happened in the OP's case.

    The second is the incorrect lane biasing in the left lane. It's not in the middle, and the car knows it's not in the middle. Instead its shifted to the right. Why???

    There is a third element of AP in 7.1 (that may have existed before) is that it excessively slows down for corners. I'm not sure exactly what happened in the OP's case, but in my own experience it slows down before the corner. I suppose with lots of corners that it's slowing in a corner in anticipation of the next corner. Either way I find the slowing to be excessive.

    Now that's all arguments against Tesla. To argue in favor of Tesla I'm getting a little sick of people using AP on twisty undivided roads. What are you trying to do? Kill someone???
     
  16. S4WRXTTCS

    S4WRXTTCS Active Member

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    Umm, I think you're lying about your location or you wouldn't have said that. :p

    But, more seriously you are entirely correct and that's what google is learning with their autonomous cars. In their case the car is simply following the law by the letter and it's causing people to crash into it because people don't follow the law exactly when driving. The other problem is the google cars are far too nice and would never be able to successfully navigate more "angry" areas.

    With the Tesla we're learning really quickly what happens when you have a driver way too over confident in a car that has absolutely no situational awareness. The car has a single camera sensor and maps from 2014 (or earlier), and it's somehow supposed to handle sweeping curves? In addition to that Tesla changes the behavior so someone like the AP who is used to one behavior from his car suddenly has to relearn his car because Tesla changed it.
     
  17. mikeash

    mikeash Active Member

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    Your brake lights will come on if the car slows suddenly due to braking (regen or friction) from autopilot. If yours didn't come on then it wasn't that sudden.

    Any driver should be able to handle the vehicle in front of them making a full-effort panic stop at any time. If they're following too close to be able to do that, then that's their own fault.

    This sounds like a problem with autopilot, certainly, but the only safety problem here was with the guy behind you.
     
  18. AudubonB

    AudubonB Mild-mannered Moderator Lord Vetinari*

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    AP - 45mph default in 7.1 is officially dangerous

    Are you an official or do you enjoy making hyperbolic thread-heads for the click-bait fun of it?

    You may or may not choose to answer that but there is a fundamental portion of your post that all here deserve to have clarified, as roads in the UK may be different enough from those in NoAm that what you write can cause confusion.

    You describe the "60 mph" road on which you were traveling as having "a series of sweeping curves". In the United States, the limited access, 2+ lane, divided median roads for which Tesla has authorized use of AP cannot, by DOT regulation, have what any would describe as "sweeping curves" on any stretch of road that is posted at 60mph or greater. Were you driving on a road for which Tesla has approved AP use?
     
  19. JenniferQ

    JenniferQ Member

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    I have been experimenting a bit, and the 45mph +5 is not implemented on many roads around me. I'd never use it on such roads but I do see if it will activate on them without the limitation and it probably does more than 90% of the time! So, I'd quit complaining and enjoy the unrestricted use of what we have so far before it really gets taken away altogether!:crying: In the meantime, drive your car as usual and learn from the errors you and it makes.

    And as for someone two cars behind you having to steer into the oncoming lane, that's their problem. Entirely. And all officials and insurance companies would more than likely rule that way.
     
  20. thegruf

    thegruf Member

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    Yes - otherwise Tesla should not permit the AP to be enabled.

    Accepting there may be some language differences here, again these were gentle curves on an open road with no obstructions or blind spots, easily taken at 60mph+

    The issue at stake is that wherever Tesla get their speed limit data from (clearly not just the road signs) has major errors in it.
    So what is posted as a 60mph road, to the Tesla suddenly appears to have no known limit - i have witnessed this many times that the speed limit indicator on the IC just disappears showing no known limit.
    This is when the car slows to 45mph (assuming a 40mph liit as it doesnt know any better).

    Then when this happens it slows firmly but not sufficiently to illuminate the brake lights.

    Now on an dry, open road (and I know you should always be prepared to slow down in reposnse to the vehicle in front) in broad daylight with good visibility you simply dont expect the vehicle in front to lose 20mph in the middle of a gentle curve without warning or indication. Sure the guy behind could have been more attentive and the guy behind him, but this is exactly how accidents happen. Most of the time no big deal, but occcasionally somebody gets caught out.

    To take a constructive tone to this situation one thing Tesla could consider is an audible notification to the driver that it has lost speed limit information and is about to default to 45mph. Yes I know - more bongs.

     

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