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Sudden Unexpected Acceleration today

Discussion in 'Model 3' started by AZM3, May 4, 2018.

  1. mongo

    mongo Well-Known Member

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    I'm still thinking a 'clutch' flappy paddle on the wheel. Good for limited power and coasting (yeah I know, going downhill in neutral is illegal...) two paddles would allow extra regen to slow.
     
  2. derekmw

    derekmw Member

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    Maybe he wants this solution. Whenever you step on the accelerator, the following happens:

    (On screen) You have just pressed the accelerator pedal. Did you mean to press this? YES / NO
    If 'YES' selected:
    - Are you sure? YES / NO
    If 'YES' selected
    - accelerate
    else
    - alert - 'haha, you dummy, you pressed the accelerator pedal instead of the brake pedal!'
    else
    - alert - 'haha, you dummy, you pressed the accelerator pedal instead of the brake pedal!'​

    Driving will become cumbersome in traffic but at least you won't blame the car next time it accelerates unexpectedly.
     
    • Funny x 12
  3. Daniel in SD

    Daniel in SD Well-Known Member

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    All the discussion of throttle pedal position is sort of irrelevant. The poster claims that his wife pressed the brake pedal. Teslas have a standard hydraulic brake systems. If you are pressing down hard on the brake pedal the car isn't going anywhere no matter what the drive unit does. Now I suppose it's possible for there to be a failure in the ABS/VSC solenoids that cuts brake pressure and a simultaneous failure of the throttle control but that seems highly unlikely.
     
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  4. copyhacker

    copyhacker Member

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    This.

    The Revisionist History episode mentioned in this and every other SUA thread goes into great detail on this. There has never been a car made whose accelerator pedal can overpower the brake pedal.
     
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  5. Daniel in SD

    Daniel in SD Well-Known Member

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    Yep but on cars with ABS I think it is physically possible for the car to override the brake pedal. I'm pretty sure that's an entirely independent system than the throttle control even on a Tesla so you'd need two uncorrelated failures at the same time.
    When the Lexus unintended acceleration incidents were in the news I tried flooring the accelerator and pressing the brake at the same time in my old Lexus. The car stopped fine.
     
    • Informative x 1
  6. BioSehnsucht

    BioSehnsucht Model 3 LR

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    If you're already moving at great speed it's possible for the brakes not to overpower the motor(s)/engine (due to the pads fading before they can significantly reduce speed), but from a stop generally speaking all cars should have more braking force than the power train can overcome. If you're moving slowly, typically, the brakes should still win.
     
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  7. wk057

    wk057 Senior Tinkerer

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    And this is definitely a key point that keeps getting ignored.

    The cars have a lot of torque available, and on my bench I actually use the hydraulic brakes as a dummy load when testing motors. However, if the motor isn't moving, it can not break free of a solid brake press. Heck, even the puny pads of the parking brake make it almost impossible for it to break free. The performance motors can break free of the parking brake with extreme difficulty, but not the hydraulic brakes. It just sits there and struggles until the motor throws an error and gives up (few seconds).

    Here's a (private) video clip I made a while back of a small rear Model S drive unit on my bench (pretty similar specs to the 3 drive units) trying to break free of just the parking brake, which has wayyyy less force than the hydraulic brakes.



    Ramped to full throttle at least once in there, zero wheel movement.

    So yeah, sorry... no one's foot was on the brake pedal while the car was quickly accelerating. Just not possible. The accelerator pedal was pressed. User error.

    I wish folks would just get over it and move on... but, the internet.
     
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  8. Mr X

    Mr X Future Martian

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    • Funny x 15
  9. Zaphod

    Zaphod Galaxy President (former)

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    bazinga :p
     
  10. Daniel in SD

    Daniel in SD Well-Known Member

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    No the brakes can dissipate enormous amounts of energy. Sure if you ride the brakes they will build up heat and burn out which is what happened in the infamous Lexus incident here in San Diego (due to stacked floor mats pinning the accelerator, poor UI design, and driver error).
    The Model 3 (and all other modern cars) can decelerate at about 1G. Full braking at 100mph the brakes are dissipating about 800kW, way more than the drive unit can produce.
     
  11. Electricfan

    Electricfan Active Member

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    Between the driver's foot and the drive motor exists a million miles of code. Our cars are computer based. Because of that simple fact, the car can accelerate without the operator pressing the pedal. No car maker, not Tesla, Toyota or any other will ever admit it if such a software problem exists. If Tesla discovers one they will quietly download a software update and fix it. But we will never know about it. The best thing to do if your car takes off without you telling it to, if you live to tell the tale, is file a complaint with NHTSA. If enough complaints come in, its possible they can do something. Bad publicity alone will get an automaker moving to some degree. Posting on a forum is good just to let people know its happening. Thank you AZM3, and good luck.
     
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  12. mhan00

    mhan00 Active Member

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    Lmao. Read the posts above yours talking about the brakes being able to overpower motors. SUA is pedal misapplication. If people were mashing on the brake like they thought they were, the car would be slowing or stopping.
     
  13. AZM3

    AZM3 Member

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    Complaint has already been filed with NHTSA. I am not hopeful anything would come out of it as they, just like some members here, are sick and tired of hearing the same saga over and over.

    And yes Tesla, if not for hubris, can help fix whatever is wrong with a SW download. I have not heard from them but I expect the same boilerplate rhetoric - wrong pedal pressed, car accelerated, $hit happened, move on.
     
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  14. AZM3

    AZM3 Member

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    Go read up details on SUA filed on S and X on NHTSA website where people are claiming they did not touch the accelerator pedal and the car accelerated suddenly. As I said earlier “pedal” is only part of the equation, which might execute few lines of code, there are thousands other that are conditional execution based on what the software thinks it wants to do.
     
    • Disagree x 3
  15. McRat

    McRat Well-Known Member

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    The Model 3 probably won't walk through the brakes even if it lacked abuse control (limits powerbraking). It's pretty easy to prove.

    You can overpower the brakes on RWD cars with some HP and no abuse control. It's how you heat your tires at the drags. Maybe some automatics with tight converters won't, but you do it on any stick V8 car if the ECM doesn't stop you. Sometimes it will slide the front tires, hence why there is a waterbox at the dragstrip.
     
    • Informative x 3
  16. Kandiru

    Kandiru Active Member

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    OP I feel for you, have admin close thread.
     
  17. Daniel in SD

    Daniel in SD Well-Known Member

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    Drag racers often use line lock allowing them to activate only the front brakes. I assume that you have to apply just the right amount of pressure to spin the rears without it. Also the rear tires are in water.
     
  18. McRat

    McRat Well-Known Member

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    #218 McRat, May 8, 2018
    Last edited: May 8, 2018
    Line locks are for wimps. :D
    This is for a Corvette/Camaro/Mustang/Viper or similar:
    In the pits, Vaseline the fender behind your rear tires to make the rubber easier to clean off. Trust me.
    Aim your side mirror down at your tire.
    Wait until you are signaled to proceed onto the track.
    Drive around the water box if possible to keep front tires dry. Basic procedure is the same if you can't.
    Back all the way through the water box with your back tires, careful to keep fronts dry. A tire is about 80" around, you want the whole tire wet so you don't start on a dry spot.
    Roll slowly (don't sling water into your wheelwell) through the standing water, and stop on the damp concrete, NOT in the standing water.
    Wait for the official to spin his finger.
    First gear, clutch in. Thumb on top.
    Right foot ball on the brake, roll your foot or use your heel to operate the throttle.
    Hold at 5500-6000 rpm.
    Drop the clutch and put your left on brake while applying throttle to hold 4500-6000 rpm.
    Glance at mirror to make sure you are spinning the tire. Don't laugh. I've spun the tire on the wheel before, and others have torched their clutch when they thought it was the tires.
    The tires will start to pull down. Takes practice. You will notice you are needing to apply more throttle.
    Or just make a ton of smoke for kicks.
    Slowly release the brake and throttle, spinning the tires about 10 feet out of the water.
    Clutch in.
    Creep forward aligning with the 2 tire tracks. That is pure rubber you see on the ground.
    Light a single pre-stage light. Wait for the other driver to light that beam.
    Now creep SLOW until the second light just flickers then stays on. Heard about 'rollout' distance. That's where it starts.
    When all 4 pre-stage lights are lit, the track official will start the tree.

    For amateurs, there are 3 yellows, a green, and a red.
    The lights come on 0.500 seconds apart.
    Hold at ... this comes down to tires and track prep... 4500 rpm to start if things are sticky.
    Stare at that 3rd light down. Try to turn it on with your mind. You are one with the light.
    The first 2 yellows are to trick you. Ignore them. They are evil. They are from the Devil, hence the Red Light on the bottom.
    When that third yellow lights, immediately go to the floor while bringing the clutch up at the same time. If you ace it, the tach will not move until the clutch is out.
    If you wait for the green, you just got spanked HARD. It takes about 0.500 sec for a sharp person to react and move the car far enough to break the beams and start the timing.
    PULL on the gearshift HARD. It can't pop out of gear.
    Tachs have a lot of lag in 1st, with a 6500 redline, shift at 6000 as follows:
    Stab the clutch to the floor and drop it. Do Not Lift The Throttle. The clutch will unload the trans, and allow the car to shift into 2nd.
    Now open your hand fingers up. Like you're saying STOP. Palm on knob. Push hard straight way from your torso. Do not grip knob.
    At 6300, stab the clutch, BANG.
    Turn your hand upside down. Point thumb at ground. Grip knob and pull back hard. This keeps you from finding second. That's no fun.
    At a hair under 6500, stab the clutch, Bang.
    Keep into it all the way past the painted lines by at least 100'. A common mistake is to lift too early. Again don't laugh, everybody does it.
    Push the clutch in and let off the gas, pop into neutral. Don't use your rods as brake pads. Test brakes gently, quickly, to make sure the car goes straight under braking. Apply brakes more aggressively. The driver who is on the turnout lane leaves the track first. Always.

    If you are unfamiliar with a track, do a shake out run, launch then short shift, watch the car in the other lane. The turnout lane is always on the side where the pits are. Don't take a turnout at high speed. A lot of the worst crashes are after the traps. There are usually more than one turnout.
    If you break during a pass, carefully pull to the side of the lane in case you are leaking and stop ASAP and get out of car. Look for leaks. The Safety Safari will head out. They can get you to the pits usually.

    Cliff notes: The rears will spin with the rear brakes applied. If you do it without water, the fronts can slide.
     
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  19. holtz13

    holtz13 Supporting Member

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    I want to make sure I am understanding your position.

    1. Tesla computer malfunctioned and and initiated SUA.
    2. Tesla hydraulic brakes malfunctioned and did not slow down the vehicle, but acted as the accelerator, due to computer overriding hydraulic brakes.
    3. Tesla needs to drop everything that they are doing so they can prove to you it wasn’t the above issues.
    4. NHTSA is going to cover up the facts because they are sick and tired of people complaining about SUA.
    5. You refuse to believe operator error happened because, although it happens thousands of times a year, In all types of vehicles, and you weren’t in vehicle when it happened, you would rather believe numbers 1-4 above.

    If the above 5 are correct can you please answer who was shooting from the grassy knoll?
     
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  20. Joe F

    Joe F Disruption is hard.

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    NHTSA can’t help the OP. He needs to call an optometrist for an appointment and then the nearest zoo to come capture the elephant doing pirouettes in his living room which he just can’t seem to see.

    Or the ulterior motive is starting to accelerate on its own...
     
    • Funny x 5

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