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Sudden Unintended Acceleration

Discussion in 'Model S' started by Ying, Jan 24, 2018.

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  1. ken830

    ken830 Model S 85, Model 3 Performance

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    I will re-check my assumption on this. I just haven't noticed this for the accelerator before. I do notice it for the brake pedal because my foot is always over the brake pedal when in cruise/AP.
     
  2. MP3Mike

    MP3Mike Well-Known Member

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    Brake pedal does, accelerator pedal does not.
     
  3. wk057

    wk057 Senior Tinkerer

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    Tesla's logging is ridiculously thorough. Last I saw they were logging changes in both tracks of the accelerator position at up to 100Hz while the vehicle is in gear. Same with the brake pedal switch (also dual and redundant).

    As for the software, all of the autonomous functions have interlocks that prevent usage at high torque command. You're not going to see a car summon at more than a couple feet per second because this is limited and crosschecked by multiple pieces of hardware. Cruise control has a defined max rate of increase in speed which is crosschecked in multiple places as well. Full acceleration by any autonomous feature is not possible.

    The autonomous functions never show in logs as a pedal application, either. While cruising or summoning, if your foot is off the pedal the logged position is 0. If the logs say the pedal was pressed you can rest assured that the pedal is pressed.

    Also, internally, the pedal position is measured thousands of times per second. It won't accept an instantaneous change from 0 to 100% without intermediate increases in position matching real world usage. Even if you do the fastest kung fu speed kick at the pedal from 0 to 100% the hardware will get multiple data points in between as it changes from 0 to 100% and can know for certain that it was indeed a physical pedal press.

    As noted, I've actually been working to achieve a software-based control over acceleration for a while now. I literally want to launch my S down a drag strip via remote. Making this possible has been extremely difficult due to all of the safety crosschecks Tesla has put in place for throttle control. Seriously, I'm putting considerable effort into a hardware/software solution to try and get the car to do basically a full acceleration without a human pressing the pedal. There are so many safety interlocks to defeat, both hardware and software wise, that I've benched the project multiple times in frustration. I only recently managed to achieve some limited success with the project. I can assure you and everyone else that this is one area where Tesla really did their due diligence to make their control system safe and reliable. Kudos.

    Edit: Also will note, the accelerator pedal can not be commanded to physically move. Unlike the brake pedal, there is no physical connection to anything that can be commanded to move. It's just a sensor.

    If you look at my post history, you'll see I'm the last one to give Tesla a pass on something and probably the last person to defend Tesla on anything at all without a solid basis for doing so.

    This one really just needs to be put to rest. But, humans will human it seems. On a broader view, our culture has definitely been moving away from people accepting personal responsibility for themselves and their actions (or inactions) and more towards baseless finger pointing, and passing the buck, and an overall "gimme gimme gimme but I'm not going to work for it, I can do no wrong, and it's always someone else's fault" type of attitude. It's depressing and makes me fear for upcoming generations.

    Accept responsibility for your actions, and move on.
     
    • Informative x 10
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  4. ken830

    ken830 Model S 85, Model 3 Performance

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    Thanks for this comment. As long as they are logging both of the raw channels of the pedal position then I feel better. I wish the could provide more details and a snapshot of the the actual logs. And in my mind, I will have to accept that my dad just mistaken the pedal, which is where I started.

    Jason, I have been following you closely (here, on Twitter, HSR Motors, Youtube, etc) since you came to the scene years ago and I highly respect your opinions and admire (and am amazed by) your work. This is the reason I wanted to ask you about the logging and software.
     
    • Like x 1
  5. Silicon Desert

    Silicon Desert Active Member

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    Well that might be the case on a FEW ICE vehicles, but not on a Tesla. Slightly apply the brake, and press the accelerator all the way to the floor. Car goes nowhere.
     
    • Like x 1
  6. fren

    fren Member

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  7. kengchang

    kengchang Active Member

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    Tried it this mornings, when you enable AP the accelerattor slowly returns to neutral position and does not move afterward. Brake does move with the current car action.
     
  8. malcolm

    malcolm Active Member

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    Can some kind moderator copy @wk057 's posts to a separate wiki or some sort of Hacker's Insights sub-forum?. Really valuable info which get lost in the these threads and not everyone knows how to search for a forum member.

    Cheers
     
    • Like x 1
  9. DarkMatter

    DarkMatter Member

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    Olympia, WA
    I'm pretty sure only drive by cable cars move the pedal for cruise control. Never seen a drive by wire car that does it.
     

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