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2015 Tesla Accelerated into a wall

Discussion in 'Model S' started by Jjmboni, May 22, 2019.

  1. Droschke

    Droschke Member

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    Know of any reputable shop that repairs the Tesla computer systems and its electronics?
     
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  2. TKGA

    TKGA Member

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    You're right I don't understand the neural net - I was thinking of it as external to the car. That Elon is creating an army of robot cars that he will one day control.
     
  3. Saghost

    Saghost Well-Known Member

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    That's a definite possibility - but not really related to the neural net. :)

    A neural net is a form of computer programming, implemented through a whole lot of matrix math. it takes a bunch of inputs, does a series of matrix math operations on them, and delivers outputs.

    Neural nets are a way of programming by system learning. Instead of the programming telling the system exactly what to do in every case,, you load the net, initialize random values, and then train it with good and bad inputs. Every time you train it, it adjusts the scaling factors of the matrixes to make the outputs look more like the trained good outputs and reject the trained bad ones.

    The final product of the training is a set of relationships between the inputs and outputs that gives the desired system response. That's then imbedded into the car's computers and the car uses it to make decisions - in this case, it takes camera inputs and decides if there are cars, trucks, bicycles, or pedestrians in the image (along with lane lines and road signs.)

    The image processing is all happening in the car's AP processor, using a neural net trained by the mothership and downloaded to the car. that image processing has to decide there's a car stopped (or moving slowly) in front of you, or the system logic won't allow TACC to engage below 18 mph.

    Then after engaging TACC you have to have the car believe that vehicle is accelerating away with no odd indications and nothing to worry it for the car to start accelerating on its own in TACC - and even then, it accelerates pretty slowly and hesitantly.

    This theory is even more improbable than a simultaneous failure on both sides of the pedal position sensor that causes it to show full accelerator, and as discussed above that's a really, really unlikely failure mode.
     
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  4. SO16

    SO16 Active Member

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    #104 SO16, May 27, 2019
    Last edited: May 27, 2019
    Didn’t realize that. My apologies.

    Perhaps people need to watch this video so they know what to do in this situation.

     
  5. SO16

    SO16 Active Member

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    #105 SO16, May 27, 2019
    Last edited: May 27, 2019
    1. Can you provide info on which cases?

    2. Was Tesla found at fault in any cases you worked on?

    3. Don’t you think putting the vehicle in neutral (along with the brakes) is the proper method to handle an unintended acceleration on the highway?

    4. In the cases of Teslas running into the walls, do you think that at those speeds while parking, the brakes would have been sufficient?

    5. Since Teslas don’t have the vacuum situation, does your brake example still apply?
     
  6. Saghost

    Saghost Well-Known Member

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    Any Autopilot Tesla has the iBooster, which means as long as it has 12V power it has full brake boost available - there's basically a motor geared to the master cylinder piston.

    Older cars had a pressurized hydraulic accumulator, with an electric pump refilling it - I'm not sure how hard it is to run the accumulator down with the pump working.
     
  7. David.85D

    David.85D Member

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    Two related notes:

    1) Don't assume all cars have a throttle override for brake application - the requirement to make that a standard safety feature was just dropped.

    NHTSA Drops Plan to Require Throttle-Override Safety Feature

    2) Nice (older) article here about the ability of brakes to stop an engine stuck at full throttle - especially the result in the souped up Mustang that showed that with a high HP engine and high starting speed, trying to overpower a high HP engine at full throttle really stress the brakes to the limits. I would expect that older brakes, or brakes not in perfect condition, would have failed this test.

    How To Deal With Unintended Acceleration
     
  8. Az_Rael

    Az_Rael Supporting Member

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    This is a very good point. I wish it was simpler to put a 3 in neutral. On the S it was easy, click the stalk up (I do that accidentally all the time when switching cars, trying to disengage AP on our S, LOL). But in the 3, you have to click up and hold, but not click up too far. I spent a few minutes at a car wash once trying to make it work, I doubt I could do it in an emergency situation. Big downside of Tesla’s single stalk for everything design. I suppose the advantage of an EV is you could also switch it into reverse as an alternative. Not sure how hard that is to do at speed.
     
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  9. MP3Mike

    MP3Mike Well-Known Member

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    Actually the old cars had vacuum brake booster with a vacuum pump.
     
  10. PWlakewood

    PWlakewood Member

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    There are shops/people that can but Tesla is not friendly to those who chose do so without being a Tesla certified shop. As far as I have seen its better to replace with new/used/refurbished instead of repairing a damaged computer or electrical component on a Tesla unless you absolutely know what you are doing.
     
  11. Droschke

    Droschke Member

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    That was exactly my point.
     
  12. PWlakewood

    PWlakewood Member

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    What point? Replace the damaged with new or used and there shouldn't be any issues.
     
  13. dhanson865

    dhanson865 Active Member

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    AEB isn't just disabled by the "accelerator", it's also disabled by steering wheel and brake pedal.

    Essentially if you are giving the car any kind of inputs it lets you have control and AEB stays out of your way.
     
  14. Droschke

    Droschke Member

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    That take a damaged car to a back alley so-called repair shop and mess with the electronics of the car to make it right and have the car on the public road. The word "reputable" has no place in this context. It's a very subjective term anyway.
     
  15. PWlakewood

    PWlakewood Member

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    #115 PWlakewood, May 28, 2019
    Last edited: May 28, 2019
    Does the OP even know anything about the place that did the repairs? Does the OP even know what was fixed or replaced? Why assume when you dont know the facts. There are plenty of shops that will repair a car that is deemed salvaged/totalled. I have seen hundreds of totalled cars in my line of work that were repaired back to pre accident conditon that are just as safe as ones that have not been in an accident. I have also seen cars that were repaired not to pre accident conditions and those ones will not pass the inspection process therefore not be able to be licensed in this state. If a car is deemed totalled/salvaged in wa state you can't just fix it and drive it. You have to get it inspected by the state patrol before they will issue the title that clearly says salvaged vehicle. If the repair is not done properly state patrol will not pass the vehicle.
     
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  16. Droschke

    Droschke Member

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    LoL. Glad you have answered your own question. Move on.
     
  17. PWlakewood

    PWlakewood Member

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    Lol. I never assumed but others have stated assumptions so maybe you should move on.
     
  18. PWlakewood

    PWlakewood Member

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    Yup that's assuming
     
  19. Saghost

    Saghost Well-Known Member

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    If anything, the highly computerized nature should reduce the risk of an unsafe repair, since you have to provide sensor inputs in the range the computers are expecting to avoid error codes.

    The usual problems with cheap salvage cars are bent crash structures and missing airbags, neither of which are related to the fancy computers.
     
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  20. tech4cars

    tech4cars Member

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    A: I have not investigated nor studied the role of electric v. mechanical braking in a Tesla, but there could be related technical issues there as to how much braking is available from the pedal, and how quickly. Logged parameters such as whether or not the pedal is applied (brake switch signal), the brake fluid pressure, longitudinal and lateral accelerometers, yaw sensor, steering angle, and wheel rotational speeds over time can shed light on the unfolding of an incident.
     
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