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Auto lane change potentially not safe if you don't check for quickly approaching cars

Discussion in 'Model S: Driving Dynamics' started by SoxFan2004, Mar 24, 2016.

  1. SoxFan2004

    SoxFan2004 Member

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    two times today I was in autopilot and I signaled to move into the left lane. The car waited to find an opening and then moved left but a car in the left lane came up on my tail quickly. One time was way too close for comfort.

    Am I using it wrong?
     
  2. mblakele

    mblakele radial cross member

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    The current hardware can't tell if someone is closing in behind you in the target lane. It's up to you to manage that risk and make sure the lane change really is safe.

    In general lane changing is said to be one of the most dangerous maneuvers drivers make. It makes sense to me that autopilot will be very conservative about it. I think it looks for a gap proportional to your following distance setting: that knob you can turn at the end of the autopilot wand. Possibly you would be more comfortable with a lower setting?

    If a lane change looks dicey to me, I take manual control. This is especially necessary in heavy traffic where AP may never find a gap that it likes.
     
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  3. rjcbox

    rjcbox Member

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    With all respect, the driver needs to check that the lane change can be made safely before activating
     
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  4. Todd Burch

    Todd Burch Electron Pilot

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    You have to first visually ensure that there's no car approaching you rapidly from the rear in the lane you intend to turn into. Then initiate the lane change.
     
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  5. AWDtsla

    AWDtsla Active Member

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    Yes it "drives itself" but it is dumb and nearly blind. It can't see a damn thing out the back or the sides, for example. It "may" detect something when it is within a few feet.

    So yes you're using it wrong.
     
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  6. brianman

    brianman Burrito Founder

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    Recommend changing the thread title for accuracy:
    Auto lane change not safe -> Auto lane change not safe when used incorrectly
     
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    • Love x 1
  7. kort677

    kort677 Active Member

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    If you were driving a "normal" car and changed lanes and had a car run up on your rear would you blame yourself or the other driver?
    the system "assumes" that the car behind you was at a safe distance before making the move. the AP cannot identify a jerk any better than you could.
     
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  8. ecarfan

    ecarfan Well-Known Member

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    I think you are using that feature incorrectly. Please read the owner's manual that came with your car (you can access it on the center display).
     
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  9. sorka

    sorka Active Member

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    Then you might as well take out the "Auto" part because it's not really "Auto" if it can't automatically do it safely.
     
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  10. snellenr

    snellenr Member

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    And stop calling that thing in airplanes an "autopilot", since it can't safely handle automatic approaches into LAX...
     
  11. ItsNotAboutTheMoney

    ItsNotAboutTheMoney Active Member

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    It's _automated_, You press and hold the stalk to tell it to make the lane change, and it does it. No different to other automation.
     
  12. Ingineer

    Ingineer Electrical Engineer

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    The lane change assist feature relies on the 12 ultrasonic sonar sensors, of which only 2 on each side of the car are in play when trying to complete a lane change, and they can only "see" less than 10 feet away. They definitely can only detect someone immediately next to you and not closing.
     
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  13. Andyw2100

    Andyw2100 Well-Known Member

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    #13 Andyw2100, Mar 25, 2016
    Last edited: Mar 25, 2016
    There's no question that the OP was using the feature incorrectly. However I think Tesla is partially to blame, and I've been posting about this for months.

    This is what the release notes say. The instructions are crystal clear:

    Auto Lane Change.jpg


    The problem is that the marketing material is also pretty clear, and makes it sound a lot simpler than the above. Here are a couple of examples of the marketing materials:

    (I added the red highlighting.)

    Autopilot 3.jpg

    And this:

    Autopilot Options.jpg


    So while this does not excuse the OP, or anyone else from the improper operation of their cars, it is easy to understand how the OP and others could be confused.
     
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  14. BriansBucketList

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    Based on the display of adjacent cars while in autopilot (as well as what I know about the location and type of sensors used) the evaluation of what cas are ahead is pretty good, using a single camera and radar. I think the written material overstates the simplicity and safety of the autopilot lane change. There are "proximity" sensors that surround the front and rear bumpers extending to he sides, but they do not seem to evaluate the placement and closing distance of cars behind, or to the side. You can see it in the dashboard display.

    I think it's the Achilles heel of the current sensor array, although I question why the rear camera data can't be used as input. Another thing I noticed yesterday, is that despite the sensors that extend to the bumper sides, when a car slightly to my rear veered into my lane, I had to speed up to prevent being hit. The car came from the right lane, and here was no car in the left lane, so that proximity sensor could have assumed it's safe to move left, yet I had to take evasive action.

    I'm betting that it will be years before Tesla or any other company is ready to take the legal stance that it's car will keep you from colliding with another car, pedestrian, object, and take responsibility should a collision occur. I love autopilot as a tool, and it's great in lots of bumper to bumper and freeway situations, but when I took delivery, they made sure I accepted the autopilot beta status nag screen. Autopilot can get better than it is, but I doubt you'll be summoning your car from across town next year. I'd love to be wrong though.
     
  15. Andyw2100

    Andyw2100 Well-Known Member

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    There is no "rear camera data." There is only "rear camera picture" that can be displayed on a screen. It's currently a completely different system, and one that has no capability to do anything other than put images on the screen. It is nothing like the front facing camera.
     
  16. 4SUPER9

    4SUPER9 Active Member

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    At little off-topic, but if you think approaching cars are scary, try dealing with lane-splitting motorcycles. There is nothing more terrifying that traveling at 70 mph when a motorcycle decides to lane split. Using autopilot even without changing lanes can be terrifying under these circumstances. My Tesla cannot see them coming and can easily favor one side of the lane or the other. Personally, I think lane-splitting should only be legal when traffic is moving at <10 mph below the posted speed limit. In fact, there was a campaign here in California trying to educate drivers that motorcycles may lane-split, but they abandoned it after it became apparent that it was actually an endorsement of this behavior.
     
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  17. BriansBucketList

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    #17 BriansBucketList, Mar 28, 2016
    Last edited: Mar 29, 2016
    I used the word data loosely, and if it's an analog feed directly into the main panel , it could still be digitized. I believe the MobilEye Q series processor is being used, for now, to process the data from the front camera, which is analog when it enters the lens, but there's a great link I can't find that explains the whole system, and I think it would need a camera that meets certain specs. I'm betting Tesla will move this processing in house, or partner with Nvidia. Maybe they can revise the rear camera subsystem to be more than a glorified rear view cam like my other cars. Overall, it's a pretty effective patched together system, with he TACC being especially good in bumper to bumper freeway traffic. Not so much if your the first person at a stop sign or light. I just noticed the side collision warning documentation also. It's rather too late, or false alarms.
    People are going out and installing Blackvue Front and Rear cams, when there's already a cam on both ends. With demand outstripping supply, I doubt if Tesla considers this a missed opportunity. If they can do a falcon wing door, accessing a camera should be easy.
    I'm closely arching Volvo, Subaru, and other companies using Eysight or any real time image analysis software for a 360 degree bubble of protection, and maybe built in dash cams with nag screens that say don't use this if it's prohibited in your area, and don't run with scissors. I have two cheap 115 clone dash cams because I like driving the Model S so much I want clear evidence in the event a collision occurs, be it my fault, the cars fault, or the other car/drivers fault. I also get lane split all the time, and I frequently see it coming with rear view on, so I'm watching on one camera, and recording on 2. It's usually during slow creep and beep and I have TACC on.
     
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  18. GoTslaGo

    GoTslaGo Learning Member

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    #18 GoTslaGo, Mar 29, 2016
    Last edited: Mar 29, 2016
    Yes, I wish they would allow us to access the camera feed. Maybe with a usb read only port that we can save on our own external hard drive. This way we can get the images we want and Tesla could protect their product (the car's hard drive) from being accessed for legal issues.

    Also, to post on topic, I use the auto-lane change feature only when I have a clear lane with no approaching cars. I keep finding myself flicking the turn indicator off too early (old habits) and leaving the car straddling the lane markers, like an idiot. Still getting use to it. Haven't had any problems with appropriate lane changes when I remember to keep the turn signal clicking until I am in the lane.
     
  19. wcalvin

    wcalvin Member

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    LaneChanging is useful, not because it saves you from assessing the situation before initiating, but because it allows you to look around during the change without dragging the steering wheel with you as you twist. And TACC saves you from constant monitoring of the car ahead, again freeing you up to look around again.

    I recall my flight instructor cautioning me about fixating on the first plane I spotted during air traffic monitoring.
     
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  20. kort677

    kort677 Active Member

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    despite it being called auto pilot it isn't auto at all the AP feature is really just a driver assist feature, secondly it is only a beta. you cannot depend on it as being autonomous, you most maintain your focus on the road and be able to assume control over the car at any given moment.
     

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