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Autopilot failed to notice a bus today

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Stopped at an intersection behind a bus today at a red light. Decided to look for some new music so I turned Autopilot on, seeing as how I couldn't see the red/green light and that'd tell me when to pay attention (car starts moving... don't tell me you guys never use it for this, either!).

Was at a complete stop about two car lengths from the bus. Engaged AP. Car immediately lurched forward. Hit brakes fast, which fortunately my foot was already over the pedal as I'd been previously stopped. Sat for a second confused. I'm now about a car length from the bus. Verified my AP was set to 4 car lengths. Engaged again. Car immediately shot forward, hit brakes. Car displayed the warning that an object was in front of me.

Took out my phone to take a picture and the light had turned green by that point, so it looks like the bus is further away than it was (you'll see the green traffic light in the distance and cars already in the intersection). I'm wondering if a combination of the color of the bus (sky blue) plus the fact that it had a graphic of a car on it "tricked" AP into thinking this wasn't a bus in my way maybe? If you look at the bottom of the photo you'll see that the AP screen shows a car, not a large truck/bus, and that it's offset left... just like the graphic is on the bus.

I am pretty confident that either the car would have emergency braked or I would have hit the bus had I left it engaged. It definitely pulled forward full-power like it does if the person in front of you changes lanes and the lane is otherwise clear.

It definitely made me think of all those people who accidentally drove into buildings and such and the little reaction time they must have had to figure out what was going on.

EDIT: Refreshed Model S running 8.0.

IMG_2026.JPG
 
My understanding (and experience) is that when stopping behind a stopped vehicle (like at a light), engaging auto pilot moves the car very close to the vehicle in front before stopping (like I typically do when stooped at a light). Only once everyone is moving again does the car put some distance between itself and the vehicle ahead.

But despite knowing this I still keep my foot hovering above the brake, just in case. So far (after almost a year on auto pilot) the car has always stopped in time.
 
Below is approximately what the camera saw. A grayscale image using the luminosity in the Red channel. The bus is very clear.

From your description, you activated AP while both you and the object in front of you were stopped AND you were closer than the four car length setting.

Have you previously activated AP on v8.0 when both of those conditions were present?

waQYDon.jpg
 
Absolutely. I activate Autopilot in bumper-to-bumper stopped traffic coming home from the Bay Area on a daily basis. I have found historically that as I approach traffic I do so much more gracefully than AP (which tends to drive fast until it hits the brakes, as opposed to letting the regen braking do the work). I then engage once I'm stopped and let it take over safely.

I'm quite aware of how close AP will take you when stopped. The behavior was abnormal -- not only did this not seem to care that I was already quite close, it accelerated immediately and rapidly when engaging and gave no indication it would quit. Typically engaging it while stopped or behind someone will move forward very slightly if at all once you're already close.
 
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i would assume that it would recognize the bus because it's supposed to use the radar as the primary recognition and camera as a backup but this does bring up a good point, can you fool the camera with a picture, i wonder if tesla has tested this.

reminds me of fooling face unlock on a phone with a photo
 
i would assume that it would recognize the bus because it's supposed to use the radar as the primary recognition and camera as a backup but this does bring up a good point, can you fool the camera with a picture, i wonder if tesla has tested this.

reminds me of fooling face unlock on a phone with a photo
Radar isn't primary. According to Elon they now work together whereas before the camera worked alone and was primary.
 
Radar isn't primary. According to Elon they now work together whereas before the camera worked alone and was primary.
And stationary radar is yet to be turned on, awaiting more fleet learning.

Bottom line, any weirdly shaped or painted vehicles in front may not be recognized still. Always be vigilant in these situations. Note that in your case, ultrasonics would have detected the car at 5 feet or so and slammed on the brakes. That's just way too close for comfort
 
I think that last post answers my situation. If stationary radar isn't on (we were both still) then I'm guessing the imagery fooled the camera into thinking it was safe. I agree, I'm sure it would have caught the error but at the rate of acceleration it wasn't worth the gamble.

That also explains why I can't "see through" cars when stopped but can when moving (on the display of course). I didn't know it wasn't enabled.

It was definitely a reminder that the technology isn't perfect.
 
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Did you happen to notice if the IC showed the bus in front of you when you engaged AP?

One thing to keep in mind is the radar is absolutely the primary sensor when it comes to AP/TACC. The problem with radar is they don't see stationary objects. We know 8.X is supposed to change this, but we don't know exactly when it will start being effective at this. We definitely know it's not at all effective right now in detecting a stopped car ahead of the car in front of you. All the tracking seems to happen once things are moving.

The camera is used for detecting which type of car it is, and looking out for pedestrians. We don't currently really know how much it's used in AP/TACC. We know it's used for confirmation in AEB (at least until the switch over), and we know it's used for FCW.
 
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I think that last post answers my situation. If stationary radar isn't on (we were both still) then I'm guessing the imagery fooled the camera into thinking it was safe. I agree, I'm sure it would have caught the error but at the rate of acceleration it wasn't worth the gamble.

That also explains why I can't "see through" cars when stopped but can when moving (on the display of course). I didn't know it wasn't enabled.

It was definitely a reminder that the technology isn't perfect.
Note that "seeing through" cars is basically seeing that there's 2 objects in front of you with 2 different distances and speeds. That means either the car in front of you has explosively separated in two, or there's two cars in front :D

When multiple cars are stopped, radar cannot tell how many vehicles are in front.


has anyone tested the emergency braking feature to see if it actually works??? i want to test mine but dont want to damage my car if it fails...

Yeah, please don't try that. The road is not the place to test an emergency braking feature, and other drivers / pedestrians are not your volunteer test subjects either :D

I guess leave that kind of testing to the professionals :D
 
This has nothing to do with the change from Tesla OS 7 to 8, most likely when your car's Autopilot first detected the bus it was stationary.
From page 67 of my Model S Owners Manual issued before 8.0:
Warning: Traffic-Aware Cruise Control


can not detect all objects and may not

brake/decelerate for stationary vehicles,

especially in situations when you are

driving over 80 km/h and a vehicle you

are following moves out of your driving

path and a stationary vehicle or object,

bicycle, or pedestrian is in front of you

instead. Always pay attention to the road

ahead and stay prepared to take

immediate corrective action. Depending

on Traffic-Aware Cruise Control to avoid


a collision can result in serious injury or

death. In addition, Traffic-Aware Cruise


Control may react to vehicles or objects

that either do not exist or are not in the

lane of travel, causing Model S to slow

down unnecessarily or inappropriately.

Please read your owners manual as it appears you are not using Autopilot appropriately, I don't think there is any guarantee that the car will stop for the bus in this particular scenario.
 
has anyone tested the emergency braking feature to see if it actually works??? i want to test mine but dont want to damage my car if it fails...

I've long thought of testing it by suspending a wide piece of aluminum foil from a thread in an empty parking lot and then making a run at it at both low speed and high. But I just never seem to get around to it. Someday...
 
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