Warning! AP2 cars don't actually recognize speed limit signs

[whitex]

There was a speed limit change near where we live recently, from 55 to 45mph. Our AP2 car still show 55mph even though there a clear, brand new speed limit sign on that stretch. Our AP1 car can read the signs, though it does have a slight issue when it doesn't see a sign for a while, then it reverts to some old database. When traveling earlier this year through long stretches of Montana, I noticed the car would show 80mph when it saw the sign, then drop it to 70mph or even 65mph just because it didn't see a sign for a while (long stretches of highway between exists).

Anyhow, lesson to be learned, don't rely on AP2 speed limit signs. I wish they would have a way to mark that little speed limit sign to indicate whether the speed limit shown is an actual sign the car saw or the computer pulled it out of some internet database. Until then, I watch out for signs yourself and don't trust what the car says, since I didn't see any ticket and insurance increase repayment guarantee in Tesla's terms, for when you get a ticket because the car told you an incorrect speed limit.

 

[Tam]

...AP2...

Is it because your AP2 is not among first 1,000 who got the firmware update?

 

[fasteddie7]

Are you using tacc? Tacc doesn't alter speed based on signs, only when autopilot is engaged does it change based on the signs. If I'm driving with just tacc, it'll stay at whatever speed I set regardless of signs, if autopilot is engaged, it will adjust. It is my understanding that ap2 doesn't do autopilot above 35 until later this week.

 

[Dax279]

I have seen this driving through BC with my AP1. The problem is the car thought the speed was 90 rather than the posted 100.

 

[MP3Mike]

Anyhow, lesson to be learned, don't rely on AP2 speed limit signs. I wish they would have a way to mark that little speed limit sign to indicate whether the speed limit shown is an actual sign the car saw or the computer pulled it out of some internet database.

The release notes for Speed Assist specifically said that the AP2 cars don't currently use the camera for the speed limit that they use GPS data. So if you had read the release notes this wouldn't have been a surprise for you.

 

[Joe F]

Not having AP2 S/W enabled yet, I found the displayed speed limit sign wrong more than correct on unfamiliar roads where I wasn't sure what the speed limit was. That is, when is was even displayed at all.

 

[bob_p]

Along our area highways, there are several speed limit signs in ambiguous locations - which could apply to the main highway or the adjacent HOV lane or exit lane. Human drivers ignore those signs - would be concerned about the AP trying to obey signs that may not even apply to the current road.

 

[whitex]

The release notes for Speed Assist specifically said that the AP2 cars don't currently use the camera for the speed limit that they use GPS data. So if you had read the release notes this wouldn't have been a surprise for you.

Ah, yes, burried in hundreds of pages of manual we're all supposed to read every update. My point was they should indicate whether the displayed speed sign is from an actual sign or a guess using some database which should not be relied upon. Change color of the sign or put something around it so people know it's not a reliable number?

 

[lunitiks]

I'm a little surprised that the cameras (actually the ECU) don't recognize speed signs yet. This should be quite easy for the machine to learn, relatively speaking... Reason is there are not so many different signs to learn, compared to other objects that come in various shapes and forms (vehicles, people, animals etc..)

 

[mblakele]

I'm a little surprised that the cameras (actually the ECU) don't recognize speed signs yet. This should be quite easy for the machine to learn, relatively speaking... Reason is there are not so many different signs to learn, compared to other objects that come in various shapes and forms (vehicles, people, animals etc..)

Finite resources. I'm sure speed limit signs will happen, but probably other features have higher priority right now. I'd guess that the highest priority is APv1 parity on safety features, TACC, and AutoSteer. It'd be easy to push out speed limit signs because they can fall back on the GPS database, even if it isn't 100% accurate. For that matter APv1 speed limit sign recognition isn't 100% accurate either.

 

[theslimshadyist]

FWIW, I have an AP2 car running 2.52.36 (Not a Cali 1000) and my car detects speed limit signs just fine.

 

[whitex]

FWIW, I have an AP2 car running 2.52.36 (Not a Cali 1000) and my car detects speed limit signs just fine.

It seems you didn't read the manual either, and are assuming the indicated speed limit is in fact recognized from speed limit signs, which it's not. This is why I say Tesla should have a clear indicator - speed limit from an actual sign or just from some internet database. The latter of course could be out of date.

 

[theslimshadyist]

It seems you didn't read the manual either, and are assuming the indicated speed limit is in fact recognized from speed limit signs, which it's not. This is why I say Tesla should have a clear indicator - speed limit from an actual sign or just from some internet database. The latter of course could be out of date.

All I know is that every time I pass a speed limit sign, within about 3 seconds the new speed limit is displayed. Whether it's a GPS marker, a camera reading the sign, I really don't care. What I do care about is that it just works and it does for me.

 

[mblakele]

It seems you didn't read the manual either, and are assuming the indicated speed limit is in fact recognized from speed limit signs, which it's not. This is why I say Tesla should have a clear indicator - speed limit from an actual sign or just from some internet database. The latter of course could be out of date.

And the former of course could be wrong. Look around here and you'll see quite a few reports of APv1 incorrectly reading speed limit signs from adjoining roads, misreading numbers, etc. Neither method seems to be particularly reliable, so what value would a "clear indicator" add?

 

[whitex]

And the former of course could be wrong. Look around here and you'll see quite a few reports of APv1 incorrectly reading speed limit signs from adjoining roads, misreading numbers, etc. Neither method seems to be particularly reliable, so what value would a "clear indicator" add?

I've been driving with AP1 for a while, and yes it occasionally misread the speed limit, but very rarely and way less often than when the internet database kicks in. When traveling on long stretches of highway, there was never any signs to misread, the system just decided that it hasn't seen a sign for a while, so it would show me 15mph lower than actual speed limit. It would be really nice to know whether it's the fallback or actual sign being read (since there are some parts of the highway which do lower the speed limit). Of course if your argument is that not showing the source of the limit it allows Tesla to mask how badly AP sign recognition really works, that's a different story.

 

[Xminus6]

Mine changes based on recognized speed limit signs. It's missed a couple, and one in particular that I can replicate, but it does change based on the signs in my experience as the display on the dash will change just seconds after passing the sign.

 

[mblakele]

I've been driving with AP1 for a while, and yes it occasionally misread the speed limit, but very rarely and way less often than when the internet database kicks in. When traveling on long stretches of highway, there was never any signs to misread, the system just decided that it hasn't seen a sign for a while, so it would show me 15mph lower than actual speed limit. It would be really nice to know whether it's the fallback or actual sign being read (since there are some parts of the highway which do lower the speed limit). Of course if your argument is that not showing the source of the limit it allows Tesla to mask how badly AP sign recognition really works, that's a different story.

More or less. I'll add that neither of us have the right data to make that call. Anecdotes aren't data. Tesla has data, if they want to burn man-hours analyzing it. They could gather events where the GPS reading didn't match the camera reading of a sign, and try to reduce the frequency of those events. But that might not be easy with the APv1 hardware, because it's something of a black box. Anyway it probably isn't a high priority for the autopilot engineering team. If it's a low priority, then it's probably in Tesla's best interests not to indicate the data source.

For APv1 it's probably good enough if the speed data is 80% accurate, because the human driver is supposed to take over whenever there's a problem (L2). That'll have to change as Tesla moves forward with EAP and FSD.

 

[wesley888]

FWIW, I have an AP2 car running 2.52.36 (Not a Cali 1000) and my car detects speed limit signs just fine.

Hmm... When the speed assist first came out, I intentionally running back and forth at a speed sign and it didn't pick up the speed changes. Now that our cars running passive mode, I did not pay attention to it. Let me go out right now to test it out.

My street is one of those street that changed speed limit in the last year of so. GPS speed data is different from the posted speed limit. Perfect place to test it out.

BRB!

 

[whitex]

For APv1 it's probably good enough if the speed data is 80% accurate, because the human driver is supposed to take over whenever there's a problem (L2).

Good enough for whom? Probably no the cop to not ticket you for speeding.

That'll have to change as Tesla moves forward with EAP and FSD.

So not for a long while, and more than likely never with current gen AP2 (no way current HW with current sensor set will allow driverless operation without the "must be ready to take over any time" requirement). Until then, it would be nice if they just let the users decide the reliability of the shown speed limit by indicating where it came from (some may thing camera data is more reliable, others will think GPS is - based on their experiences in their areas).

 

[mblakele]

Good enough for whom? Probably no the cop to not ticket you for speeding.

Wouldn't Tesla tell you that the speed limit display is "just" a convenience feature? And that the driver is responsible for avoiding infractions?

I don't really have an argument to pursue in this thread, BTW. I've just been trying to explain why Tesla might not prioritize speed limit signs right now, and why they might not see much value in telling us where each speed limit comes from. Maybe I'm wrong and this idea of yours will show up in a future release.