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AutoPilot Crash today-Tesla response less than stellar?

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I'm not surprised. When I took my test drive a long time ago, the salesperson had my test TACC (AP wasn't out) on a congested city street and was like "let it stop for you". Thankfully it did, but I was shitting bricks the whole time.
 
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Not sure why that would be the case. Radars when used in autopilots or adaptive cruise control work basically on the doppler principle to understand if an object is getting closer or further away.

If I drive at 70MPH behind a car doing 70MPH, the radar sees the car in front of me as stationary, it is neither getting further away nor approaching me. The same applies at 50MPH, 20MPH or 0MPH.

The radar would be ignoring stationary vehicles in adjacent lanes, as otherwise it would be emergency braking when passing a vehicle stopped in the emergency lane next to you, it shouldn't ignore anything in your path.

So, unless you are referring to a known engineering issue, a radar would never ignore an object approaching you, it is simply not how a radar works.

The problem is that a stopped car, a soda can with the bottom pointed towards you and an overhead sign all look the same on radar.

Because of this, the standard approach for car radar is to start by ignoring anything that isn't moving based on the Doppler data (anything that shows closure at the car's speed.)

This is simple, but it means you don't see cars that have stopped.

Next generation is to continue with that assumption, but track things that you saw move before. This is where most adaptive cruise control is - it'll follow a car to a stop and start again, as long as it saw the car move initially.

Tesla went a step further, linking Mobileye object recognition to radar returns, so it would react to anything it saw moving on radar or that the camera thought was a car, but they still have some accidents slipping through the cracks.

Which is what the 8.1 update is about. Tesla has been building a whitelist of all the safe stationary objects that look like stopped cars on the road since 8.0 was released, and in the future your car will stop for new stopped objects that aren't recognized by the camera, too.
 
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What is AEB and how does it affect AP?

AEB is Automatic Emergency Braking, and it is completely separate from AP. It is designed to reduce the severity of an impact by reducing the impact speed by ~25MPH, but it doesn't do anything until it determines that a collision is unavoidable.

FCW, Forward Collision Warning, is another feature that lets you know about a collision before AEB to allow you act, but it suffers from some of the same problems as AP, coming over a hill to a stopped car is a problem. (And it also depends on if it is enabled and what option it is set to Early, Standard, or Late.)
 
It sounds as if you came up over a hill, which means the radar couldn't track the car in front of you. Once you came over the hill and the radar could see the car, it was stationary, and the system doesn't track that.
That's a huge problem. Other car manufacturers with emergency braking recognize a stationary object and bring the car to a complete stop. Looks like a Tesla fail.
 
That's a huge problem. Other car manufacturers with emergency braking recognize a stationary object and bring the car to a complete stop. Looks like a Tesla fail.

Every manual I've seen for one warns that it may not stop for a car in this situation, and my understanding is that Tesla does this better than most others. Do you have information indicating otherwise?

This is exactly the situation that 8.0/8.1 is intended to rectify, once 8.1 goes out.
 
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Every manual I've seen for one warns that it may not stop for a car in this situation, and my understanding is that Tesla does this better than most others. Do you have information indicating otherwise?

This is exactly the situation that 8.0/8.1 is intended to rectify, once 8.1 goes out.
Yep, last time I looked when someone claimed something similar, every manual (from BMW to Mercedes to Volvo) says it may not necessarily brake in this situation.
 
Can the AEB reducing by 25 mph be adjusted to reduce even more?

By the time it reduces your speed by 25mph, you should've had time to determine whether or not there's truly a threat, and hit the brake pedal yourself. In 8.0, this will act as a confirmation to deploy full emergency braking until the car is stopped or until you press the gas.


AEB is meant to be hands (well… feet)-on, not for the driver to observe idly as the car automagically pulls you out of impending doom.
 
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That's a huge problem. Other car manufacturers with emergency braking recognize a stationary object and bring the car to a complete stop. Looks like a Tesla fail.

That's not necessarily true. Any car that relies on K-band or 77GHz doppler radar has this inherent problem that stationary traffic is not easy to detect because it looks like any stationary feature on the road, such as a speed bump or a piece of debris on the road or even an overhead sign / traffic light.

They all rely on cameras and image recognition to recognize a car, and certain things can prevent that from working correctly, ranging from an older system that was not trained against modern cars (my previous 3-year-old Audi stopped recognizing the Fiat 500 and Ford Transit Connect vans by the time I turned it in), weirdly painted vehicles or lack of brake lights, etc etc etc.

Inherently, only the LIDAR based systems can reliable measure and range large solid objects, but these systems also have the additional problem that from a long distance, it's difficult to target non-LIDAR-reflective materials like matte paint jobs and it can mis-read reflective objects as threatening (e.g. a garbage truck that has paper flying out of it looks the same to LIDAR as a truck throwing metal blocks at you)
 
I wonder what the Tesla salesperson would say.

You've obviously documented this in an objective(???) manner.

... The salesperson suggested that my friend not brake, letting the system do the work...

Suggested? Um, okay.

... The purpose of this post isn't to assign blame...

Sure.

... I really am excited about the car and don't want to throw away months of research because of this incident. Tesla needs to address this...

Cheers, mate, I can see your excitement.
 
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on my test drive, on the freeway, we were in AP, and i was testing the lane change capability.. and i purposely put the blinker on when a car was in my blind spot. I had to take over to prevent lane change. Point being, I did not trust the car to not get into an accident, and I would've not listened in this case. My car speed and approach time of the stopped car would've not computed in my head, and I would've played it safe. Especially the first time with AP where my skepticism meter is higher with self driving.

But what I don't get... even with all of the explanations on here, is how an object the size of a car, stopped or not, doesn't alert the TACC to slow down. if it were a wall, would it slow down?

Can the AEB reducing by 25 mph be adjusted to reduce even more?

there is a setting where you can adjust the reaction time... early, standard, late.. i think i actually saw that this am while messing with my settings.
 
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The car was in autopilot mode. It was accelerating up the hill and he was not steering, but had his hands right near the steering wheel, per instruction.
One thing not mentioned, but might apply (and help your buying decision) is that there is a dashboard visualization of what the AP system "sees". I would presume in this case the car in front didn't show up in that visualization, which may be a warning that the system didn't detect the stationary car in front.
 
When I test drove I had to wait for the "test drive guy". Which makes sense that a trained Tesla rep. go on the test drives. I have let several people drive my car and always remind the driver the car is NOT AUTONOMOUS!!!
And I repeat this mantra several times :) This test drive seems to have been conducted with a very inexperienced employee. As others have stated crest of hills, stationary cars etc.......... AP does have some limitations but is awesome after some experience with it. If you order your Tesla , ICE will become ancient history and you will not be sorry. Good luck!
 
on my test drive, on the freeway, we were in AP, and i was testing the lane change capability.. and i purposely put the blinker on when a car was in my blind spot. I had to take over to prevent lane change. Point being, I did not trust the car to not get into an accident, and I would've not listened in this case. My car speed and approach time of the stopped car would've not computed in my head, and I would've played it safe. Especially the first time with AP where my skepticism meter is higher with self driving.

But what I don't get... even with all of the explanations on here, is how an object the size of a car, stopped or not, doesn't alert the TACC to slow down. if it were a wall, would it slow down?



there is a setting where you can adjust the reaction time... early, standard, late.. i think i actually saw that this am while messing with my settings.
This is related to the parked car and walls problem.

TACC systems are designed to reject stationary objects as tracking targets because they are typically parked cars or walls and TACC is not tasked to handle that (it's only tasked with tracking a moving car in front essentially).
AutoSpeed - Technology of Adaptive Cruise Control

That's why in all TACC manuals, it says if the system is tracking a moving car and it moves away from the lane, revealing a stationary car, the TACC will not brake for the stationary car.

In that case, it's up to the AEB to do braking.