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Questions after recent two accidents

Discussion in 'Model X: Driving Dynamics' started by dapao, May 16, 2016.

  1. dapao

    dapao Member

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    After the second customer claim that AP didn't stop the car, I was thinking that Emergency braking can be available when AP is on? Is it the same for other fancy brands of cars? Such as benz or bmw?
     
  2. loganintx

    loganintx Member

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    Read the article again and read Tesla's explanation of why emergency braking did not engage.
    Another driver says Tesla’s autopilot failed to brake; Tesla says otherwise
    "Data points to Simpson hitting the brake pedal and deactivating autopilot and traffic aware cruise control, returning the car to manual control instantly. (This has been industry-wide practice for cruise control systems for many years.) Simpson's use of the brake also apparently disengaged the automatic emergency braking system, something that's been standard across Tesla's range since it rolled out firmware version 6.2 last year."
     
  3. loganintx

    loganintx Member

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    If the car thinks that you are in control it does NOT try to override your control. If it senses that you have not reacted and taken control then it will attempt to take control and apply emergency braking. This could change in the future through software update though.
     
  4. systemcrashed

    systemcrashed Please Reboot

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    The driver is at fault here BUT it sounds like she was not well versed in the limitations of the Emergency braking and Autopilot systems. If a collision is imminent and there is no driver input, the car will avoid a crash by applying the brakes. Same happens when AP is engaged, although the brakes are applied past the point your reflexes would respond. What happens in a situation like this is that the driver senses the system is not braking in time and then begins to apply the brake, if braking pressure is not forceful enough (depending on distance and speed) there will be a collision. Once the car senses any input by the driver (even a delicate application of the brake), it will not override that. What is done to compensate in other cars is something called Emergency Brake assist, this will apply 100% or brake force even if the pedal is tapped insufficiently but quickly, in an imminent crash scenario. I am not aware of a braking assist in a Tesla but I definitely am not finished learning how these safety systems operate and what their limitations are. I would spend a long time observing a car's behavior and response to certain situations before I put my full faith in these "emergency" failsafes.
     
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  5. JimVandegriff

    JimVandegriff Member

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    When reading about the accident, the question that came to mind for me was how many car lengths had the driver set as the minimum distance required before the car automatically slowed. If say the distance was 2 car lengths then the autopilot system would not have slowed her in time to avoid the accident. If she noticed that she was approaching the other car quickly, applied the brakes (and thus turned off autopilot), and still slammed into the other car, then it should warn us all to 1) set the minimal effective car length feature for autopilot to the highest distance possible, and 2) remind us that we are each responsible for the driving of the vehicle even with autopilot engaged. I hope no one was injured.
     
  6. loganintx

    loganintx Member

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    If it was set to a lower number then the cars would've been closer together and TACC would have aggressively slowed her car down.
     
  7. systemcrashed

    systemcrashed Please Reboot

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    Emergency Braking is designed to be able to stop the car and avoid a collision or greatly reduce the speed prior to a collision, this verbiage is included to protect the manufacturer and keep the driver responsible. The closer you follow the harder the system will brake even to a stop (but collision risk IS higher). The question I would like to know the answer for is , at what distance and speed does the TACC predict a potential collision?
     
  8. mdevp

    mdevp Member

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    Does anyone know the time between when she applied the brake till impact? Then we can surmise whether the AP/TACC wasn't going to work (if it was less than a second for eg). If it's say 5 seconds or more, it's easy to see she disabled everything prematurely by tapping the brake and glided into the accident.
     
  9. cclaygo

    cclaygo Member

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    The only way the car will not stop is if it does not sense an obsticle. She hit the car....the car would have stopped if it was in control and sensed the obsticle. In the end, nobody should think the auto pilot means you don't have to be aware and ready. It's a convenience feature, that is all.
     
  10. llngoc

    llngoc Member

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    So instead of collision avoidance, the car manufacturer should put in suicide mode which will actively direct the car to run into another car without the driver's full attention. I bet the accident rate will actually go down. :D

    This is so much like at work. Once you put in automation for the process, whenever something goes wrong, it is always the automation even though there were big red flags printed in the log along the way. It is just too convenient to blame the Convenient feature. (no pun intended)
     
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  11. pchan

    pchan Member

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    So, Model X doesn't have brake assist?? How about Pedestrian Detection? Or Rear Cross-traffic Alert? I am just picking some features on the Hyundai Tucson website ... I know it is unfair because Model X is $130K and Hyundai is $30K ... It is like comparing apple to orange. Oh, how can I forget everything can be easily software updated over the air 'some day' on Tesla while Hyundai cannot. Maybe that's why Hyundai have all those options now while Tesla doesn't.
     
  12. cclaygo

    cclaygo Member

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    It does have break assist...thanks for the ridiculous Hyundai comparison and complete inability to read the other posts.
     
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  13. pchan

    pchan Member

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    This is the spec of Model X ... it seems to have automatic emergency braking, but not brake assist:
    Model X Specifications

    My partial ability to read post #4:

    And here, it describes how the automatic emergency braking:
    https://www.teslamotors.com/sites/default/files/tesla_model_s_software_6_2.pdf

    "Automatic Emergency Braking will stop applying the brakes when you press the accelerator pedal, press the brake pedal, or sharply turn the steering wheel"

    So ... sorry, no brake assist yet. It sounds ridiculous, but it seems like it is either you (1) trust the car completely to let it 'reduce the impact' for you without touching the brake pedal, accelerator pedal, or sharply turn the steering wheel or (2) you take over to stop the car but don't expect any help from the automatic emergency braking ...

    Please don't take it personal, and don't shoot the messenger. I don't short Tesla.
     
  14. cclaygo

    cclaygo Member

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    That's odd, I happen to own one and have experienced multiple times how the car stops miraculously all by itself. Try reading the posts of actual owners giving their input. I don't take it personal, just a ridiculous post and comparison on your part.
     
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  15. systemcrashed

    systemcrashed Please Reboot

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    To be fair, I believe @pchan was referring to "Brake Assist" as it is defined by other car manufacturers, not Tesla. There is a difference. Tesla does not currently have an equivalent "Brake Assist". Let me explain the difference. As I understand it from the literature, I have yet to receive my Model X. What Tesla refers to as "Collision Avoidance Assist" is not the same as "Adaptive Braking Assistant" on a BWW for example (see its description here BMW Technology Guide : Adaptive Brake Assistant ) Tesla owners who have had this feature in a previous vehicle should be aware of this difference. The Tesla will not apply any brake if it senses the drivers input on the brake pedal even in an emergency braking event, but vehicles with "Brake Assist or Assistant" will provide 100% of the brake when an emergency braking event occurs even if the driver has applied insufficient force on the brake pedal.
     
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  16. PeckerWood

    PeckerWood Member

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    One item to take away from this chain is an on board recorder might be in order. Couldn't be too far off from trouble code recording. I would also like some means to use the cameras to record on SD card some kind of loop so in the event of an accident you might need an impartial witness.
     

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