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NTSB Wants Information on Tesla Autopilot Accident

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A Model S using Autopilot crashed into a firetruck near Los Angels on Monday prompting inquiry from the U.S. National Transportation Safety Board, according to a report from Bloomberg.

The Tesla driver was reportedly traveling at 65 mph when he rear-ended the truck. There were no injuries in the crash.

The Bloomberg report says the NTSB has not decided if it will launch a formal investigation. The agency is currently “gathering information.”

The Culver City Fire Department shared a photo of the accident.


The NTSB announced earlier this year findings of an investigation into the first known fatal crash involving a car using an automated driver assistance system. The agency said that “operational limitations” of Tesla’s Autopilot system played a ‘major role’ in the 2016 crash that killed one person. The driver’s 2015 Tesla Model S collided with a semi-truck while the car’s Traffic-Aware Cruise Control and Autosteer lane-keeping assistance features were being used.

Tesla’s repeated line on accidents is that “Autopilot is intended for use only with a fully attentive driver.”

And, the NTSB noted in multiple reports that the driver kept his hands off the wheel for extended periods of time despite repeated automated warnings not to do so. Further, NTSB said the drivers hands were on the wheel for just 25 seconds during a 37-minute period that Autopilot was engaged. Still, the agency said Tesla’s system needs more safeguards – better systems to alert drivers and detect surrounding traffic.

Monday’s collision reportedly occurred while the firetruck was parked in an emergency lane at the side of the highway attending to another accident.

 
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I have a "2016 MS P90DL AP1" and I use emergency distance set at Max. In this setting I feel best protected.
Now why is emergency breaking not enabled regardless of Autopilot but on ALL the time ?!
And why is the car not automatically preventing the driver from accelerating from low speed into an object ?!
 
TACC is not designed to detect STOPPED traffic when there is nothing between the car and the stopped object. Warnings about this abound, but some still try to test Darwin's theory.
So, so true. Mainly only Tesla owners know the difference but every now and then we see some ignorant Tesla Autopilot driving behavior like this that tells me the driver never read the Owners Manual.
 
I couldn't read through all of the posts but - in CA it is the law to be aware of emergency situations and to move away from them. Emergencies don't suddenly appear, unless they are just arriving. Still, you can see a firetruck in front of you over all the cars if that's the case. Being on that stretch of freeway often, there is always heavy traffic in that area. If the lane the driver was in was moving at 65, they were taking a carpool lane to get around the slowed traffic. I wonder if he had his stickers. When there is an emergency, every lane the CHP designates is an emergency lane. The driver can and should be ticketed for 1) not moving over for emergency vehicles and 2) driving too fast near an emergency situation - both ticketable offenses. This person was paying attention to everything except driving.
 
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Oh, I figure they will just adjust the distances unannounced. So you will still have a “1” but it won’t follow as close anymore.


I'm really confused why anyone would go with any setting that's not 7 on a highway...?

I want to be safe as hell in my car, especially while I'm not directly in control. It's best practice, anyway, to always follow at 1 carlength/10 MPH, and on the highway I can't think of any reason why I would want to lower that to anything less than 7.

In more congested traffic I've turned it down, at lower speeds, to avoid people cutting in and out in front of me and making me lag behind. But on the highway, it's beyond me why you would go any lower than 4-5... thoughts?
 
So, so true. Mainly only Tesla owners know the difference but every now and then we see some ignorant Tesla Autopilot driving behavior like this that tells me the driver never read the Owners Manual.

Expecting everyone to read every page of a dry-as-hell manual is ridiculous. There's a reason the phrase "RTFM" exists - because most people don't and never will.

Personally, I think a major problem with the function is it's name. Calling it "autopilot" just sounds like you can set it and forget it, but that's definitely not the case.
 
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I don't think this is much of a mystery. Remember the Driver's Ed class when they taught you about "outdriving your headlights" at night? That was driving so fast that by the time you saw something in your headlights you couldn't stop in time.

The Tesla's radar operates much like a headlight transmitting on 77 GHz. Radars, just like headlights, flashlights and flash cameras, follow what we engineers call "the 1/r^4 law": the outgoing radio signal or light drops off according to the inverse square law and the return also drops off by the inverse square law. This creates a very well defined range limit that is hard to increase just by using a more powerful radar. (Consider all those idiots in a huge sports stadium trying to photograph the action on the field with a flash camera.)

I discovered my Tesla's radar range limit pretty early in a very similar situation: I was driving up I-15 to Escondido in the carpool lane when I saw two stopped cars, one in the breakdown lane and one in my traffic lane. The radar never saw it, at least not before I'd already decided a drastic manual response was warranted. (We stopped OK).

I seem to recall from the NTSB's information dump from the Florida crash that a range reading of 205 meters means "infinity", so the range is obviously less than that even under ideal circumstances (I don't remember if an exact number was given). 205m is about 7 seconds of driving at 65 mph.
 
I have a "2016 MS P90DL AP1" and I use emergency distance set at Max. In this setting I feel best protected.
Now why is emergency breaking not enabled regardless of Autopilot but on ALL the time ?!
And why is the car not automatically preventing the driver from accelerating from low speed into an object ?!

Automatic Emergency Braking (AEB) is enabled all the time, unless you manually disable it using the button in settings. And even if you do that, it re-enables itself the next time you get in the car. It's not designed to prevent an accident, as it only kicks in when the car thinks a crash is unavoidable. It simply slows the car down so there's less impact energy.

There aren't that many cars available today that try to prevent drivers from accelerating into objects. And I would personally never use such a system. I don't want my car to override my input. As long as I'm driving, I want my decisions to be final.

I'm really confused why anyone would go with any setting that's not 7 on a highway...?

I want to be safe as hell in my car, especially while I'm not directly in control. It's best practice, anyway, to always follow at 1 carlength/10 MPH, and on the highway I can't think of any reason why I would want to lower that to anything less than 7.

In more congested traffic I've turned it down, at lower speeds, to avoid people cutting in and out in front of me and making me lag behind. But on the highway, it's beyond me why you would go any lower than 4-5... thoughts?

I fully agree, there's zero reason to use anything but the maximum setting on a highway. Following closer won't get you where you're going any faster.
 
This ignorant driving behavior reminds me of this old legend - Cruise Control as Auto Pilot

Personally I would be mortified if my friends and associates learned I failed to understand the workings of a vehicle assist system before using it - especially if my life and the safety of everyone around me depended on it.

A manual isn't the answer in terms of User Experience. Someone else suggested a required video course to be watched before using the feature...and while that has it's drawbacks, that's a way better UX and way more effective than hoping people go to the right page in the manual IMHO
 
I don't think this is much of a mystery. Remember the Driver's Ed class when they taught you about "outdriving your headlights" at night? That was driving so fast that by the time you saw something in your headlights you couldn't stop in time.

The Tesla's radar operates much like a headlight transmitting on 77 GHz. Radars, just like headlights, flashlights and flash cameras, follow what we engineers call "the 1/r^4 law": the outgoing radio signal or light drops off according to the inverse square law and the return also drops off by the inverse square law. This creates a very well defined range limit that is hard to increase just by using a more powerful radar. (Consider all those idiots in a huge sports stadium trying to photograph the action on the field with a flash camera.)

I discovered my Tesla's radar range limit pretty early in a very similar situation: I was driving up I-15 to Escondido in the carpool lane when I saw two stopped cars, one in the breakdown lane and one in my traffic lane. The radar never saw it, at least not before I'd already decided a drastic manual response was warranted. (We stopped OK).

I seem to recall from the NTSB's information dump from the Florida crash that a range reading of 205 meters means "infinity", so the range is obviously less than that even under ideal circumstances (I don't remember if an exact number was given). 205m is about 7 seconds of driving at 65 mph.

You're a boss.
 
There is a very simple reason accidents like this keep happening.

TACC and emergency braking cannot detect a completely stopped vehicle.

The radar works by bouncing return pulses off targets and returns relative speeds of vehicles.

A sudden deceleration will be detected, as will slowing traffic, as the ACC radar will start detecting the delta in traffic speed. Stopped vehicles return a very high target speed which is necessarily filtered out due to the chance of picking up road signs, etc*. Stopped vehicles do not appear to be there to the AP computer and will not be detected by the AEB system.

*The radar module requires vehicle speed information to make this decision which is gathered from the front wheels (I believe). But I do not know that much about how Tesla's Bosch ACC is implemented because it's somewhat different to other cars.

I suspect that Elon's statement on multiple radar bounces refers to using more than the primary radar return pulse as the tracking pulse, so the processor in the radar module is capable of returning more than one deceleration rate. Those return pulses were always there, but it's a matter of using some advanced DSP to filter and process them, because they're probably some 20-30dBs below the main return pulse. It's certainly very clever technology but not a solution to this problem.

The only way to intervene here is if the autopilot camera recognises the situation, and as far as I know, it can only use brake lights as additional information for AEB, and not in the case of a lack of radar data (this is perhaps because brake light detection is very difficult to reliably do, with the variety of shapes and sizes of brake lights, but I am only speculating here). APv2 probably doesn't even implement brake light detection yet although it will depend on how advanced the NN is. (Did anyone notice that in the v1 autopilot keynote demo, where the car stopped for the stopped car, that the brake lights were on even though the vehicle was completely stationary? Wanna bet the radar did nothing here, and it was all driven by the brake light detection, tuned for Model S, and that if the brake pedal wasn't being pressed by a brick, they'd be explaining why the new autopilot piled into the back of a brand-new Model S in clear conditions?)

This is the fundamental issue with APv1 and APv2 as simple lane hold autopilots and it is the reason these types of accidents happen only when drivers are not paying attention.

If people pay attention while using these systems they would be able to intervene in sufficient time and these accidents would not happen.

The owners manual does make these limitations clear so it's not as if Tesla is unaware of this problem and I'm sure they're testing methods to improve this.
 
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Automatic Emergency Braking (AEB) is enabled all the time, unless you manually disable it using the button in settings. And even if you do that, it re-enables itself the next time you get in the car. It's not designed to prevent an accident, as it only kicks in when the car thinks a crash is unavoidable. It simply slows the car down so there's less impact energy.

There aren't that many cars available today that try to prevent drivers from accelerating into objects. And I would personally never use such a system. I don't want my car to override my input. As long as I'm driving, I want my decisions to be final.
...
I fully agree, there's zero reason to use anything but the maximum setting on a highway. Following closer won't get you where you're going any faster.
I have never had any indication of AEB unless in auto speed mode so I am respectably disagreeing.
Maybe I am a too good driver for the car not to trust me ;)...

There where some instances where cars was raced into buildings as the driver pushed the wrong pedal.
I think they would appreciate the car to think for them... at least giving the car a speed limitation when objects in front.
Of course an optional function that could be disabled at will.
 
There is a very simple reason accidents like this keep happening.

TACC and emergency braking cannot detect a completely stopped vehicle.

....

This is the fundamental issue with APv1 and APv2 as simple lane hold autopilots and it is the reason these types of accidents happen only when drivers are not paying attention.

If people pay attention while using these systems they would be able to intervene in sufficient time and these accidents would not happen.

Exactly!

I’ve seen my Volt lurch at stopped vehicles when the lead radar tracked vehicle moves out of the way. Alarming at first but entirely preventable if your hands are on the wheel and your eyes are on the road and engaged in the situation. I think it’s entirely possible for a person with APv1 style auto steering enabled to be sufficiently tuned out so as not to be able to react in time. This is the whole problem with simple lane based auto steering, the driver needs to be fully engaged but is often lulled into thinking all is ok. Basic human nature I suppose. With simple lane based auto steering enabled, what should the drivers minimum reaction time be? 800ms? 1s? 1.5s?

At the CES Mobileye presentation Amnon was saying basically level 2 is “hands on the wheel” (Nissan Propilot) and in level 3 the driver could take 10 seconds (!!!) to re-engage.. so what about simple lane based systems like APv1? He called this level 2+.. but it’s still unclear what the drivers min response time should be.. or how you enforce that.

Interestingly Toyota ACC will automatically disengage at low speeds if the lead vehicle moves out of the way and the radar can’t see a new moving target ahead. At higher speeds (such as this accident) it would have still lurched into the fire truck without driver intervention though.

I was involved in an accident like this long ago in the EV1... late at night in the carpool lane on 55 S (SoCal) approaching the “orange crush” I was behind a truck that jumped out of the carpool lane (over the double yellow) and my thought at the moment was that he didn’t want to get sucked onto I-5 S and was making a drastic late second course correction. No.. it turned out there was a stopped vehicle dead center in the carpool lane. My personal reaction time was insufficient to avoid an accident and I clipped the vehicle (ripped the side mirror off the EV1). Talk about a heart pounding moment. Suffice to say slower speeds and a greater following distance would have helped tremendously. Perhaps someday APv2 will be able to handle this better.. but current radar based systems and inattentive drivers can be a really bad situation.
 
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This is a very good article which helps explain why the Tesla could have ran into the back of the fire truck. In fact most auto pilot cars could have the same issue if they use radar like Tesla. Stationary items are not read as well as moving items. The accident most likely occurred by another car changing the quickly in front of the S living the car with little time and not recognizing what was in front of it. Not, even going to talk about the driver and traffic awareness.

Why Tesla's Autopilot Can't See a Stopped Firetruck
 
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I've driven cars with adaptive cruise cruise since 2011, and none of them are good at stopping for stopped cars. That's just the current technology. Period.

And for those intelligent enough to understand what your tool does and doesn't do, then it is a useful tool to have.

If you think your band saw is going to stop when it hits your finger, you better not use a band saw -- or wait for one of these: Saws Cut Off 4,000 Fingers a Year. This Gadget Could Fix That.

Meanwhile, many people are intelligent enough to use a band saw without cutting off their finger, and many people are intelligent enough to use adaptive cruise and related technologies by being careful and ready to take action for obstacles in the lane.

The bottom line for me is that no AP or TACC should drive into a parked vehicle on the road, in the lane of travel of the vehicle, and easily seen or detected. That's just unacceptable. Period.