Phantom Braking misunderstanding

[fholbert]

Let me help you. Hopefully it makes sense.

If there is no vehicle detected / no change in the within scope surrounding environment, it might mean there is a glitch and the vision processing has been jammed for unknown reasons. That is a disorienting situation and triggers a safety alert as continuing to keep driving would be dangerous.

It is much like a situation when JFK crashed due to lack of visual reference points.

Good comparison, the glitch may be in the mapping software too.

The car may be okay, but the mapping software is showing something that's different than what the car is seeing. I'm sure we've all seen changes to the road, maybe improvements that the mapping software hasn't picked up yet.

 

[KLam]

Interesting article

GPS Spoofing Is Now Affecting Airplanes In Parts Of Europe

Incidents of GPS spoofing leading aircraft off-course in the Middle East now have company in Europe. Russia is the source.

www.forbes.com

 

[jeffkruse]

I’ve gotten really good at having my foot on the accelerator and reacting fast enough to keep the “breaking “ to less than a 5 mph reduction in speed. It might prevent a tailgater from hitting me. It’s actually easier to not use the cruise control.

 

[derotam]

Let me help you. Hopefully it makes sense.

If there is no vehicle detected / no change in the within scope surrounding environment, it might mean there is a glitch and the vision processing has been jammed for unknown reasons. That is a disorienting situation and triggers a safety alert as continuing to keep driving would be dangerous.

It is much like a situation when JFK crashed due to lack of visual reference points.

First to be clear, I am not fully discounting your theory, just making observations that seem to contradict it at least in part...

The user mentioned that it happened a second time at the same place but changed to a DIFFERENT speed than the first time. One would assume(I know what happens when you assume...haha) that any glitch would not be so variable.

That is a disorienting situation and triggers a safety alert as continuing to keep driving would be dangerous.

This specific wording I would have a problem with. In cases where the car gets so confused that it needs to alert the driver, it generally goes full red screen and MANDATES that the driver take over, thereby disengaging any AP functions. I'm with you generally until you make comments talking about the car seeing a "dangerous" situation or triggering a safety alert.

Obviously more data would be required to better theorize about all this.

One data point that I will toss in here...similar action by my vehicle but different circumstance. My car on a highway I drive in the mornings, the car drops the speed limit and the TACC speed setting down to 55, 60 or 65 MPH(seemingly random so far) at various times while in traffic(not totally packed but not light either). So same end result basically but different scenario. Might be two totally different things, might not. More data needed, haha.

 

[enemji]

Good comparison, the glitch may be in the mapping software too.

The car may be okay, but the mapping software is showing something that's different than what the car is seeing. I'm sure we've all seen changes to the road, maybe improvements that the mapping software hasn't picked up yet.

That is why Tesla chose to use realtime visual processing as opposed to scanning HD images of the roads like Waymo.

That being said, I am sure there are conditions that it has not accounted/programmed for. In those cases, it stops AP/FSD and alerts the driver to take over.

The situation where it hits the brakes real hard are in my experience what was described earlier - empty roads with no vehicles as well as no road signs. Essentially no visual reference available to indicate it is going in the right direction.

 

[enemji]

This specific wording I would have a problem with. In cases where the car gets so confused that it needs to alert the driver, it generally goes full red screen and MANDATES that the driver take over, thereby disengaging any AP functions. I'm with you generally until you make comments talking about the car seeing a "dangerous" situation or triggering a safety alert.

I agree with you as well. It was the alert or brake. I would have expected it to alert the driver as well but then it doesn’t and hits the brakes real hard. I would suspect mirages but it has done the same at night when there are no mirages.

 

[Supcom]

You are right, there is something that is causing the computer to change the speed limit and TACC setting but that isn't phantom braking... Also you just said it happened at the same spot which gives some permanence to the specific braking incident. Without knowing the exact spot at a minimum there would be no way for anyone to really provide much more insight to why it may be happening.

The system changing what value it is changing the speed limit too is interesting as well.

I have had issues where the car changes the speed limit when crossing into a new county. It seems similar to the issue where you turn onto a rural highway and the car sets the speed limit to 25 mph default because it hasn't seen the 55 mph sign yet.

 

[acoburn73]

You are right, there is something that is causing the computer to change the speed limit and TACC setting but that isn't phantom braking... Also you just said it happened at the same spot which gives some permanence to the specific braking incident. Without knowing the exact spot at a minimum there would be no way for anyone to really provide much more insight to why it may be happening.

The system changing what value it is changing the speed limit too is interesting as well.

Hasn't happened in that spot since, and I drive it every day and put on autosteer just to check. In fact, a couple of longer drives from my home to the airport on a highway went well - no issues.

 

[acoburn73]

Except the user stated that it happened at the same spot a second time, which starts to bring in other possibilities.

Your theory is interesting but I don't see any reason why "if no other vehicles for x amount of time then rapidly slow down and ignore the posted speed limit" would be in the logic of the vehicle. Not saying it isn't true but it doesn't make sense.

That was not the same spot I referenced. The I-70 through Kansas is not the same location as the place where the speed limit on TACC adjusted from my set 70 mph to 50 mph, then 65 the next time. This location is in a busy area of south Denver metro area (C-470 and Santa Fe), while the no-traffic, perfect call day situations in western Kansas were a totally different situation.

 

[derotam]

That was not the same spot I referenced. The I-70 through Kansas is not the same location as the place where the speed limit on TACC adjusted from my set 70 mph to 50 mph, then 65 the next time. This location is in a busy area of south Denver metro area (C-470 and Santa Fe), while the no-traffic, perfect call day situations in western Kansas were a totally different situation.

My statements were based on YOU saying:

Today in the same spot it adjusted from my preset speed of 70 mph to 65 mph. Same spot where once it dropped to 50 mph, then 55 mph. So something about that spot makes it want to slow down.

We can muddy the waters and add more instances with different data but I was trying to stay with the 2 instances at the "same spot".