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Collision Avoidance vs. Automatic Emergency Braking

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BerTX

Active Member
Supporting Member
May 2, 2014
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Texas/Washington
So I have no Tesla and no other vehicle that would have these features, and I'm confused.

I thought Tesla already had collision avoidance released when TACC was released.

Now, today, it is announced that Automatic Emergency Braking is coming to a Tesla near you.

I don't know the difference. From the descriptions I read, they do the same thing. Did I just misunderstand collision avoidance? I read about people not being brave enough to see if the car would stop for a stopped vehicle in front of them, so they obviously expected that to be an existing feature.

Maybe collision avoidance is a TACC-controlled feature, and automatic emergency braking works under normal driver-controlled conditions?

Somebody educate me, please!
 
I believe it is along the lines of what you described above. I test drove an autopilot car yesterday and the rep say TACC will stop me automatically, but outside of being in cruise, it will only alert me to hit the break. Now, with 6.2, it will do the breaking as well just as if I was in TACC.
 
I drive an AutoPilot vehicle, and this is how I understand it:
Collision avoidance is a separate system from TACC. While you have TACC on, the car will slow down or completely stop depending of what the car in front of you does. That is just the TACC with its adaptive cruise capability. Collision avoidance is just the alarm that goes off if the vehicle thinks that you have an impending collision. It is on even when TACC is off during normal driving conditions. The Collision Avoidance system will NOT brake for you, it will only give you an audio/visual warning.

The Emergency Braking feature that will be rolled out will take the collision avoidance feature one step further and Model S will apply the brake for you if it is certain that a collision will occur.
Also one important distinction is that TACC is an autopilot convenience feature which means that it only comes with the Tech + Autopilot package. Emergency braking and Collision Avoidance are Active Safety features which are standard on all Model S vehicles that have the supporting hardware.
 
I'm probably in the minority here, but I have a fundamental problem with the car making those types of decisions for me without my permission due to the possibility of software and/or sensor failures that could cause emergency braking where it was not warranted. I know that is probably a very unlikely scenario and one that probably won't ever happen, but it's in the back of my mind constantly when I drive an autopilot car. I don't have that fear with my non-AP P85. I probably should seek therapy.
 
I'm probably in the minority here, but I have a fundamental problem with the car making those types of decisions for me without my permission due to the possibility of software and/or sensor failures that could cause emergency braking where it was not warranted. I know that is probably a very unlikely scenario and one that probably won't ever happen, but it's in the back of my mind constantly when I drive an autopilot car. I don't have that fear with my non-AP P85. I probably should seek therapy.
If a sensor fails/is covered, the system is automatically disabled an an alert shows on the dash. If it does indeed brake when it shouldn't, touching either the accelerator pedal or the brake pedal will stop the system as well. I do know that Mercedes already has these safety features and I don't hear of it being a problem. If it is tuned right, I'm sure it will save many accidents.
 
If a sensor fails/is covered, the system is automatically disabled an an alert shows on the dash. If it does indeed brake when it shouldn't, touching either the accelerator pedal or the brake pedal will stop the system as well. I do know that Mercedes already has these safety features and I don't hear of it being a problem. If it is tuned right, I'm sure it will save many accidents.

That makes me feel better. I have trust issues, can you tell? lol
 
I'm probably in the minority here, but I have a fundamental problem with the car making those types of decisions for me without my permission due to the possibility of software and/or sensor failures that could cause emergency braking where it was not warranted. I know that is probably a very unlikely scenario and one that probably won't ever happen, but it's in the back of my mind constantly when I drive an autopilot car. I don't have that fear with my non-AP P85. I probably should seek therapy.
I agree but if that's the case we also wouldn't drive a Mercedes, Audi, BMW, and other luxury vehicles.
 
I encountered two situations recently where my Model S forcefully applied the brake incorrectly. Nothing was around my vehicle and I was on the highway in both cases. I applied the accelerator and took control of the vehicle to resolve. Autopilot isn't perfect and requires an alert driver to be used properly.
 
I'm probably in the minority here, but I have a fundamental problem with the car making those types of decisions for me without my permission due to the possibility of software and/or sensor failures that could cause emergency braking where it was not warranted. I know that is probably a very unlikely scenario and one that probably won't ever happen, but it's in the back of my mind constantly when I drive an autopilot car. I don't have that fear with my non-AP P85. I probably should seek therapy.

ha not sure you need therapy - i think it's a valid concern. my Collision Avoidance doesn't beep at me very often, but i'd say 90% of them are false positives. sometimes triggers in parking structures going about 8mph with no moving vehicles nearby. sometimes triggers on the road when a car isn't actually presenting a danger. i'm concerned about the car slamming on the brakes in situations like that, as it would be unnecessary, unexpected to me, and (worst of all) unexpected to anyone who is potentially behind me.

but Djung makes a good point that other cars have this tech and we don't hear about big issues, so maybe save me a seat at your therapist appointment =)
 
It is not clear to me that the emergency braking feature and the collision avoidance warning will be using the same algorithm. That is, I'm not sure we can assume that emergency braking will be activated in all the cases that we not get a warning. The exact wording: "Collision Avoidance Assist feature automatically engages the brakes to reduce the impact of an unavoidable frontal collision". That sounds like it will NOT avoid a collision, just reduce the impact of it. THe warnings happen far sooner.
 
It is not clear to me that the emergency braking feature and the collision avoidance warning will be using the same algorithm. That is, I'm not sure we can assume that emergency braking will be activated in all the cases that we not get a warning. The exact wording: "Collision Avoidance Assist feature automatically engages the brakes to reduce the impact of an unavoidable frontal collision". That sounds like it will NOT avoid a collision, just reduce the impact of it. THe warnings happen far sooner.

that's a really good reading of the exact quote. looking forward to release notes, but now i'm thinking you're right.
 
If a sensor fails/is covered, the system is automatically disabled an an alert shows on the dash. If it does indeed brake when it shouldn't, touching either the accelerator pedal or the brake pedal will stop the system as well. I do know that Mercedes already has these safety features and I don't hear of it being a problem. If it is tuned right, I'm sure it will save many accidents.

Computers do crash. Software does have bugs. Can anyone prove the correctness of the algorithms that Tesla uses to control the brakes and that the algorithms are fault tolerant under all possible failures of the sensors, computer, and other hardware. I hope they have redundant computers in case one fails and they continuously monitor the system for faults, or at least have a fail safe mechanism that recognizes there is a problem.
 
Computers do crash. Software does have bugs. Can anyone prove the correctness of the algorithms that Tesla uses to control the brakes and that the algorithms are fault tolerant under all possible failures of the sensors, computer, and other hardware. I hope they have redundant computers in case one fails and they continuously monitor the system for faults, or at least have a fail safe mechanism that recognizes there is a problem.

In a rational world, it would only have to be better than the average human driver. Or maybe better than an expert human driver. That's a lot less than perfect. In the real world, it will probably have to be shown to be considerably better than even an expert driver. But that's still a lot less than perfect.

Don't make the perfect the enemy of the good.
 
There seems to be some confusion in this thread between what others on TMC have been referring to as Collision Detection vs. Collision Avoidance.

We recently had Collision Detection introduced, in version 6.1 of the firmware. With Collision Detection, the Model S sounds an alarm if a collision is imminent. This is in the 6.1 release notes as "Forward Collision Warning." Note that is also may come up during TACC because the TACC only has "limited braking ability." In other words, the TACC may not brake enough to prevent collisions, and may get you into a situation where it then warns you to brake.

No one has Collision Avoidance yet. Collision Avoidance, as I understand it, will have the car taking whatever evasive action is necessary to avoid a collision. That could be braking, of course, but it could also be steering, and I imagine it could even be accelerating if that's what it would take to avoid a collision.

The "Emergency Braking" announced last week is neither of these things. It really does sound like the emergency braking is only going to kick in to reduce the impact of a collision that is going to happen.

Disclaimer: I guess I could be wrong about any of the above, but I really don't think I am.
 
There seems to be some confusion in this thread between what others on TMC have been referring to as Collision Detection vs. Collision Avoidance.

We recently had Collision Detection introduced, in version 6.1 of the firmware. With Collision Detection, the Model S sounds an alarm if a collision is imminent. This is in the 6.1 release notes as "Forward Collision Warning." Note that is also may come up during TACC because the TACC only has "limited braking ability." In other words, the TACC may not brake enough to prevent collisions, and may get you into a situation where it then warns you to brake.

No one has Collision Avoidance yet. Collision Avoidance, as I understand it, will have the car taking whatever evasive action is necessary to avoid a collision. That could be braking, of course, but it could also be steering, and I imagine it could even be accelerating if that's what it would take to avoid a collision.

The "Emergency Braking" announced last week is neither of these things. It really does sound like the emergency braking is only going to kick in to reduce the impact of a collision that is going to happen.

Disclaimer: I guess I could be wrong about any of the above, but I really don't think I am.

So the Tesla doesn't have collision avoidance like the bmw i3, but for now it has collision warning and emergency braking, along with automatic deacceleration/braking while in TACC.


 
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I don't put a lot of stock in unreleased features, I'm more interested in existing vehicles that have equal or better systems to what Tesla currently offers. (Some have lane keeping, but that seems so far to be the only improvement anyone has over what Tesla is currently offering (well that and self parallel parking))
 
I don't put a lot of stock in unreleased features, I'm more interested in existing vehicles that have equal or better systems to what Tesla currently offers. (Some have lane keeping, but that seems so far to be the only improvement anyone has over what Tesla is currently offering (well that and self parallel parking))

Self parallel parking is coming, according to the stats page. Not sure how it will work, since the parking sensors don't (yet) see the curb for me when I parallel park manually.