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It’s not poor AP it’s poor emergency braking...

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zambono

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Mar 1, 2016
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So the recent crash into the fire truck has brought up more news articles and some Tesla discussions but I think it’s all directed at the wrong feature. Most of us here know that AP needs to be supervised, but these incidents just show me how poorly crash avoidance and emergency braking is implemented in Tesla vehicles. In countless other brands if there is a huge immobile object in front the vehicle will stop.
 
So the recent crash into the fire truck has brought up more news articles and some Tesla discussions but I think it’s all directed at the wrong feature. Most of us here know that AP needs to be supervised, but these incidents just show me how poorly crash avoidance and emergency braking is implemented in Tesla vehicles. In countless other brands if there is a huge immobile object in front the vehicle will stop.


Could you point to specifically which brands this is the case and/or tests of that functionality? This has been said over and over again, but in all of the German cars I've owned with ACC + AEB, the manual lists the same limitation (objects that come into view that are stationary are not considered for emergency braking).

Heck, the Audi camera-only system that's standard on '17 models doesn't even have any AEB above 45mph according to the manual. They just call it "pre-sense city".
 
So the recent crash into the fire truck has brought up more news articles and some Tesla discussions but I think it’s all directed at the wrong feature. Most of us here know that AP needs to be supervised, but these incidents just show me how poorly crash avoidance and emergency braking is implemented in Tesla vehicles. In countless other brands if there is a huge immobile object in front the vehicle will stop.
Actually we don't know if other brands will stop for the same situation (a fire truck angled partially in the lane). All emergency braking systems are designed and tested based on a standard test target (directly fully in lane and not angled). I cover this here:
AEB simply won't work

For other brands, even if their emergency braking system failed to brake, it would not hit the news, so we would never know about it. This accident hit the news because it is a Tesla and autopilot was allegedly involved (note that we don't know enough details to know if AEB activated or not).
 
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So the recent crash into the fire truck has brought up more news articles and some Tesla discussions but I think it’s all directed at the wrong feature. Most of us here know that AP needs to be supervised, but these incidents just show me how poorly crash avoidance and emergency braking is implemented in Tesla vehicles. In countless other brands if there is a huge immobile object in front the vehicle will stop.
Not going to argue on the effectiveness of Tesla's implementation, but I will say don't base your opinion on what you see in other car brands commercials. Every other system as well does not guarantee it will come to complete stop in all cases. AEB's main function is to mitigate collision. Yes, if it can come to stop in some circumstances, which is great, but that really is it's secondary function. I urge you to read any of the other manufacturer's manuals and fine print in their commercials and advertising, it will say exactly that.
 
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Honestly, I've found AP2 to be making huge improvements in this area. I can drive around garages and streets with parked cars and see all of them blink on and off the screen even at odd angles. It'll be an open question whether or not the MobileEye camera can be improved at all in this regard. The previous NTSB report stated that it was trained against "hundreds" of rear-end images of cars.

That NTSB report also tested the Model S against the Mercedes C class's stereoscopic cameras + DISTRONIC PLUS auto emergency braking and found that both poorly recognized perpendicular cars.


So, unless I see some evidence to the contrary, it does not seem like it's the case that most other cars on the market work any differently.
 
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Actually we don't know if other brands will stop for the same situation (a fire truck angled partially in the lane). All emergency braking systems are designed and tested based on a standard test target (directly fully in lane and not angled). I cover this here:
AEB simply won't work

For other brands, even if their emergency braking system failed to brake, it would not hit the news, so we would never know about it. This accident hit the news because it is a Tesla and autopilot was allegedly involved (note that we don't know enough details to know if AEB activated or not).
It may be worth noting that while the other brands stop for the standard car and pedestrians targets, Tesla EAB is not even claiming to be designed for stopping, simply to reduce speed to some speed (20mph is it) for predicted car collisions and nothing on pedestrians that I have seen.
 
It may be worth noting that while the other brands stop for the standard car and pedestrians targets, Tesla EAB is not even claiming to be designed for stopping, simply to reduce speed to some speed (20mph is it) for predicted car collisions and nothing on pedestrians that I have seen.

From the manual:
Warning: Automatic Emergency Braking is not designed to prevent a collision. At best, it can minimize the impact of a frontal collision by attempting to reduce your driving speed. Depending on Automatic Emergency Braking to avoid a collision can result in serious injury or death.

So maybe everything just worked as designed.
 
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Volvo's 2018 drive assist system can't detect parked vehicles or stationary objects... or people, bicyclists and motorcyclist which AP1 can.

"Pilot Assist does not react to people or animals, or small vehicles such as bicycles and motorcycles. It also does not react to low trailers, slow moving, parked or approaching vehicles, or stationary objects."
Pilot Assist II
 
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It is AP that will need to continue to be improved. AP knows the car, the road around it, and the intent (its direction of travel).

AEB is always going to be difficult as it doesn’t know the drivers intent. Are they going to swerve? Follow the lines? False emergency braking is very dangerous. It can mess up the driver (was going to switch lanes into a gap but car slammed on brakes). It can mess up person following (and checking their texts in their cellphone).
 
From a reddit comment from the recent fire truck incident, it seems that there was a truck he was following that swerved to the right suddenly because of the parked fire truck. That might have something to do with it.

The driver of the Tesla is my dad's friend. He said that he was behind a pickup truck with AP engaged. The pickup truck suddenly swerved into the right lane because of the firetruck parked ahead. Because the pickup truck was too high to see over, he didn't have enough time to react. He hit the firetruck at 65mph and the steering column was pushed 2 feet inwards toward him. Luckily, he wasn't hurt. He fully acknowledges that he should've been paying more attention and isn't blaming Tesla. The whole thing was pretty unfortunate considering he bought the car fairly recently (blacked it out too).
Edit #1: He had some minor cuts and bruises, but nothing serious. As for the 65mph detail, the braking system could've intervened before the collision, but there's no way he could tell.

I thought it was odd, since Tesla said that they could activate AEB for any object in the road with v8.1 even if the camera could not detect an object. It was detailed in this blog post "Seeing the World in Radar".

After careful consideration, we now believe it can be used as a primary control sensor without requiring the camera to confirm visual image recognition. This is a non-trivial and counter-intuitive problem, because of how strange the world looks in radar. Photons of that wavelength travel easily through fog, dust, rain and snow, but anything metallic looks like a mirror. The radar can see people, but they appear partially translucent. Something made of wood or painted plastic, though opaque to a person, is almost as transparent as glass to radar.

The net effect of this, combined with the fact that radar sees through most visual obscuration, is that the car should almost always hit the brakes correctly even if a UFO were to land on the freeway in zero visibility conditions.

So a solid large object in the road, such as a firetruck, should have caused AEB to activate. Maybe it did and reduced the impact of the collision? Without seeing the logs, it might be hard to tell. the driver apparently said that he could not recall if AEB had activated or not.
 
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