General

Autopilot disengages to reverse causing accident

edited November -1 in General
I got into an accident today because I was not used to autopilot. I usually drive a model 3, but this time I was driving a model X. I had autopilot on and wanted to change lanes on a congested freeway and turned on the signal stalk. The car started to slow down to find a spot and I decided to take over since it was taking so long so I instinctively flip the right stalk up as I do in my model 3. What happened was that this put the car into reverse. Not realizing this and upon seeing space up in front of my vehicle, I pressed the gas pedal which caused my X to move backwards, rear-ending the vehicle behind me. At first I thought it was all my mistake, that I probably pushed the brake pedal or that I'm too used to 3 to cancel autopilot with the right stalk.

I then recreated this scenario in a less congested area. I turned on autopilot and followed a car to a red light which slowed down both of us to 5 mph. Then I flipped the right stalk up to cancel autopilot and it indeed put the car into reverse. At higher speeds when I tested around 30 mph, flipping the stalk up to cancel autopilot put the car into drive.

Well, the accident occurred and my insurance premiums will go up as well as I have to shell out money to repair my trunk door. I also sent an email to Tesla and will see what their response is. I'm sure this is not the first time this has happened and it should be fixed with a firmware update. No driver would go from autopilot to reverse. It's the last thing on my mind when I am driving on a freeway trying to merge. Hopefully Tesla can fix this problem and I guess I'm also giving a PSA. I feel like there were several design flaws in this scenario that if fixed, could've prevented this from occurring.
«134

Comments

  • edited November -1
    On S/X all of the AP functions are on the dedicated AP stalk on the left. Having AP controls on different stalks on the two different models is poor UX but having an AP command share the same control motion as putting a car into reverse could be deadly. Hopefully this will change. This story seemed so weird I searched online and found a video about Model 3 AP controls that shows these functions. The driver even remarks, "it's a little unnerving to push up on the stalk to cancel AP but it's never gone into reverse for me."
  • edited November -1
    You can also cancel autopilot by turning the wheel.
  • edited November -1
    I’m having a little trouble believing this story. First, when using auto lane change, the car doesn’t slow down to find a spot in the next lane. Second, you can only shift from drive to reverse if you’re stopped or moving less than 5mph, but you said you were moving forward trying to change lanes. I don’t doubt that someone could accidentally shift into reverse, but it seems unlikely in the scenario you described.
  • edited September 2019
    Using auto lane change does slow down if the lane I was in was open and the lane on the right was congested. It was in fact what prompted me to take the autopilot off because I would’ve missed the exit if the autopilot took too long.

    Regardless, you can try autopilot and let the car slow down to 5 mph and then hit the stalk up on an x or a s. For me the car went into reverse. Tesla should have kept the stalks consistent on the 3 and the x/s and maybe should not let drivers disengage from autopilot directly to reverse when hitting the stalk up at low speeds.
  • edited September 2019
    AP will definitely slow down to make a lane change. This is an area that will hopefully improve. The car sometimes slows very abruptly which feels dangerous and rude to drivers following.
  • edited September 2019
    Also, I’m not sure that people should rely on turning autopilot off with brakes or turning the steering wheel since it disrupts the car from normal moving motion. I believe the stalk method to be the safest and smoothest. Why cause stress for the driver behind you when you tap the break or swerve the car a little and bother the passenger to disengage autopilot.
  • edited November -1
    @lilbean, turning the wheel will cancel steering and lane change control but not speed control. Only hitting the brake or cancelling with a stalk will fully cancel AP.
  • edited September 2019
    I have to barely touch the brake pedal to disengage the AP on my Model 3. I haven't tried yet, but I bet I could do it with my left foot and barely slow at all...
  • edited September 2019
    Im having trouble with the part where OP switched to reverse while moving forward in autopilot, and then pushed the accelerator and it reversed the car that was apparently moving forward.
  • edited September 2019
    If you're moving at speed, hitting the gearshift lever into the "R" position will put the car in Neutral. At slow speeds, it's possible to go from moving forward to being in reverse.

    That said, all of this is resolved by the OP's very first sentence: "I got into an accident today because I was not used to autopilot."

    Don't use autopilot if you're not familiar with it.
  • edited November -1
    Model S will not switch to reverse if you are moving forward at more than a few miles per hour. I have tried that on my model S.

    So the issue is simply OP has mistaken the control on the X versus the 3.
  • edited September 2019
  • edited November -1
    Correct, autopilot will not go into reverse if you are driving at higher speeds. I tested it at 30 mph and it just disengaged autopilot and did not allow me to go into reverse. Once the car slows down to 5 mph, try hitting the right stalk up and you will see the car goes into reverse. Your car can still move forward slowly even though the “gear” is in reverse.

    I think I am used to autopilot, as I have used it for thousands of miles on the 3. It was when I switched to the x to drive did I get confused. So then it must mean I am used to autopilot on the 3, but not the x. In any case, I still think it’s a bug that needs to be fixed or Tesla should’ve kept the same stalk on the left for the 3 but it’s too late now.

    Sad thing is I had to explain to the couple I hit that I was confused by autopilot. Their first words were that I should not be using autopilot on the freeway in congested areas and they are probably never going to buy a Tesla after this incident which is a shame. I didn’t have time to explain the nuances of autopilot but I still enjoy driving Tesla’s and will continue owning in the future.
  • edited September 2019
    that is not a bug. Its a learning curve between different Tesla models.
  • edited September 2019
    It’s not a bug that at 30mph it disengages autopilot and at 5 mph it goes into reverse?

    Do you or anyone drive both a 3 and an s/x? This would only happen to a very small subset of people who drive both designs.
  • edited November -1
    It sounds like you hit the stalk that you thought was the AP stalk and instead you switched the car into reverse. If you try switching the car into reverse at 30mph, it does not change transmission but it disengages AP. If you try switching into reverse at 5mph it switches to reverse.

    Im not sure what you are asking.
  • edited September 2019
    Shouldn’t the stalk disengage autopilot into drive or neutral no matter what speed it disengaged at so there’s is a consistency? Having a cutoff of 5 mph (not sure if it is, but I was able to go into reverse at 5 mph) to go into reverse just seems dangerous. Autopilot can function at 5 mph as well when traffic slows down or merging as what happened to me.
  • edited November -1
    This sounds like a learning curve.
  • edited September 2019
    I guess I should learn how to drive an x then. But a good design would also prevent user error like this.
  • edited September 2019
    agreed. and im sorry, but so would reading the manual.
  • edited September 2019
    Don't use autopilot if you're not familiar with it.

    That's a Catch 22: You can never get FAMILIAR with something unless you USE it.

    That being said, it is the users responsibility to inform ones self with AP. If the different models have stalks in different locations, the user must be very diligent with it's operation.


    I feel sorry for hiltxan, but its mostly on him.

    I'm now going to go out and see if I can get my MX to go into REVERSE while simulating his conditions. Hope it can be done in a parking lot!!
  • edited September 2019
    Parking lot may not work since autopilot cannot engage due to lack of lines. But I was also able to go from adaptive cruise control to reverse at slow speeds around 5 mph (I had to deliberately line my car up behind a parked car to slow my car down)

    Let me know if anyone is able to recreate this scenario with autopilot.
  • edited September 2019
    @hiltxan: Okay, I believe you now.

    All Tesla models will let you shift from drive to reverse if you're going slower than 5mph. The difference is that the Model S/X don't use the gearshift for AP control, but if you shift into neutral that should disengage AP.

    As I discovered today when going through a car wash, it's very challenging to shift a Model 3 into neutral. You have to push the gearshift up (or down if coming from reverse) and hold it for more than one second before it will go to neutral. This is necessary since you also push up the gearshift to cancel Autosteer. In the S and X, you can just push the gearshift up (or down) to shift into neutral, since there's a separate stalk for Autopilot.
  • edited November -1
    It's just interesting to think about since I work in healthcare and we have what we call a "swiss cheese model" in analyzing errors. This would apply to anyone in engineering or aviation and other fields as well. There were multiple times this error could have been prevented but it just so happened that it all aligned together to cause an accident. I treat it as a case study to learn from.

    1. Driver has to be used to driving a 3 and then switching to an X/S. (Could have been prevented with same configuration on the 3 and the X/S)
    2. Engaging autopilot and have a need to disengage at low speeds.
    3. Hitting the gearshift stalk up to cancel (out of instinct due to the model 3) on the X.
    4. Car not disengaging autopilot into neutral at slow speeds (Tesla firmware should be consistent in having autopilot disengage to neutral or drive no matter what speed, definitely not reverse).
    5. Of course user error and not understanding how to correctly cancel autopilot.

    Most people who only drive the 3 or the S/X without having to switch between the two models will probably never encounter this scenario to begin with and can't possibly imagine how easy it is to forget which model you are driving when you're in a fast-thinking situation such as merging on a freeway.
  • edited September 2019
    I feel for you, what got you there was that you assumed the two models operated the same (both being Tesla cars).

    Just like how I used to misspell words because I didn’t look them up because I thought I knew how to spell them. Except misspelling words didn’t get me in a minor car collision.
Sign In or Register to comment.