Surprising [and funny!] Problem with Auto Pilot

[oldgoat1968]

I have experienced this twice. So I know it wasn't just a "once in a lifetime" glitch. While driving along Florida Highway 20 between Panama City Beach and the Defuniak Springs Supercharger, I'm tooling along fat, dumb and happy on AP at about 60 mph. Suddenly, the speed drops to 20 mph. I glance at the Traffic Aware Cruise Control indication on the dash and it shows it is set to 20 mph! I'm scratching my head when I look at the speed limit indicator just to the left of the speed indication. It shows the speed limit is 20. It took a second for this to set in but apparently the camera caught the road sign indicating that I was on Route 20 and interpreted it as a speed limit 20 sign. I ran the exact same route a few days later and the experiment is repeatable!! Clearly, there is a need for some sort of software adjustment here. Makes me wonder what would happen in California while travelling down Route 1. Or how 'bout the Washington DC beltway, Highway 495? Does the Tesla interpret that as 1 mph or 495 mph speed limit? This could lead to some interesting situations . . .

 

[Sogorman]

What FW version are you on? This is the first report of the AP camera changing the set speed after the speed has been set (not using the + MPH offset to prime the AP speed)

 

[pdxgibby]

Good thing you weren't on Route 150.

 

[ReddyLeaf]

I've seen an 85 mph sign on the consul when in a 55 mph zone. Yes, that could be a problem.

 

[davidc18]

This is now happening on 595 in the express lane heading east from weston to ft. lauderdale. The speed was set at 75 and dialed back to 55 and slowed immediately. We were lucky there were no tailgaters. This is a safety issue and now Tesla is actively decreasing safety with autopilot updates.

 

[jeffro01]

This is now happening on 595 in the express lane heading east from weston to ft. lauderdale. The speed was set at 75 and dialed back to 55 and slowed immediately. We were lucky there were no tailgaters. This is a safety issue and now Tesla is actively decreasing safety with autopilot updates.

Is there something new in the feature set that has recently changed? In my car, it has never changed speeds on it's own based on the changing speed limit signs. If I'm in full AP and the road goes from 65 to 55 my speed doesn't change from 70 (I drive at least 5 over) to 60 on it's own, I have to interact with it...

Jeff

 

[CHG-ON]

Were you driving next to an access road that had a 20mph limit? It is a known issue that the camera can sometimes pick up the limit sign on a side road and change the speed. I have not heard of it misinterpreting a route sign as a speed limit sign. I do have one stretch where it reads a 65 sign as 85. I reported it to them. That one kind of makes sense to me. 55-85 doesn't.

 

[riceuguy]

If it's not officially a freeway (Interstate, perhaps?), the latest update restricts the car to 5 mph over posted speed limits, but ONLY if autosteer is on. So, if the car thinks the speed limit is 55 and you're at 75, yes, the car would slow to 60 on its own (it will not inadvertently speed up unless you had manually set the target speed faster). The speed limit misinterpretation is the interesting part to me here. I've had this kind of problem in school zones when it's not shcool times (car assumes speed limit is 20 mph but it's really 45 mph at that time).

 

[wjhepworth]

Makes me wonder what would happen in California while travelling down Route 1. Or how 'bout the Washington DC beltway, Highway 495? Does the Tesla interpret that as 1 mph or 495 mph speed limit? This could lead to some interesting situations . . .

Funny you should mention it but I literally had AP almost stop on the Beltway (495 near DC) after having changed a lane. My cruise speed still read 60 but the car seemed very confused after the lane change and I had to hit the accelerator myself after it dropped down to around 30MPH and refused to accelerate.

 

[Max*]

Funny you should mention it but I literally had AP almost stop on the Beltway (495 near DC) after having changed a lane. My cruise speed still read 60 but the car seemed very confused after the lane change and I had to hit the accelerator myself after it dropped down to around 30MPH and refused to accelerate.

Which section? I drive the NoVa section of the beltway often enough, and the only "glitch" I've seen is that it sometimes gets confused with the express lanes speed limit (shows 65, when the local lanes are only 55). Otherwise it's pretty smooth.

 

[Az_Rael]

I wonder how this will work here in California where we have alternating speed limit signs for different vehicles. Cars might be 70mph, but trucks are 55mph. And the signs alternate along the entire length of the highway.

 

[thimel]

I wonder how this will work here in California where we have alternating speed limit signs for different vehicles. Cars might be 70mph, but trucks are 55mph. And the signs alternate along the entire length of the highway.

Autopilot properly ignores the truck speed limit signs.

 

[Debo]

Autopilot properly ignores the truck speed limit signs.

So at least I got that going for me, which is nice.

 

[FlasherZ]

I have experienced this twice. So I know it wasn't just a "once in a lifetime" glitch. While driving along Florida Highway 20 between Panama City Beach and the Defuniak Springs Supercharger, I'm tooling along fat, dumb and happy on AP at about 60 mph. Suddenly, the speed drops to 20 mph. I glance at the Traffic Aware Cruise Control indication on the dash and it shows it is set to 20 mph! I'm scratching my head when I look at the speed limit indicator just to the left of the speed indication. It shows the speed limit is 20. It took a second for this to set in but apparently the camera caught the road sign indicating that I was on Route 20 and interpreted it as a speed limit 20 sign. I ran the exact same route a few days later and the experiment is repeatable!! Clearly, there is a need for some sort of software adjustment here. Makes me wonder what would happen in California while travelling down Route 1. Or how 'bout the Washington DC beltway, Highway 495? Does the Tesla interpret that as 1 mph or 495 mph speed limit? This could lead to some interesting situations . . .

This happens on US Highway 50 for me occasionally. Once a week or so when I'm on US 50.

I also have a problem where, in the town near me, the highway (45 mph) curves to the right and a side street exits off to the left in a "Y" configuration. The camera can see the 25 mph speed limit sign about 250 feet ahead on that side street and suddenly slows the car down to 30 mph even if you're staying on the highway.

 

[RogerHScott]

So does someone know for a fact that it is "reading" the physical signs and not using your GPS position
to get the speed limit from a database based on your location? I thought I'd heard somewhere that the idea
that it could "read" signs was a myth. But that, too, could be a myth

 

[FlasherZ]

So does someone know for a fact that it is "reading" the physical signs and not using your GPS position
to get the speed limit from a database based on your location? I thought I'd heard somewhere that the idea
that it could "read" signs was a myth. But that, too, could be a myth

Yes, it reads signs. A temporary speed limit was put up locally, guaranteed not to be in any database, and that day the car reacted.

That's also why occasionally, it will read a US Route 50 marker as a speed limit 50 sign on a 55 mph highway.

 

[RogerHScott]

That's also why occasionally, it will read a US Route 50 marker as a speed limit 50 sign on a 55 mph highway.

Given how many highways/routes/etc. have identifiers indistinguishable from plausible speed limits, it seems like this would
frequently cause problems. I imagine they must be preferring signs that contain the word "speed" and avoiding signs containing
words like "road", "route", "highway", and perhaps the names of states. Tough problem.

 

[Tree95]

Oregon uses a curly sort of font that can confuse the software. I've had 65 been read as 85 more than once on I-5.

 

[FlasherZ]

Given how many highways/routes/etc. have identifiers indistinguishable from plausible speed limits, it seems like this would
frequently cause problems. I imagine they must be preferring signs that contain the word "speed" and avoiding signs containing
words like "road", "route", "highway", and perhaps the names of states. Tough problem.

Indeed this sign might be a fun one for autopilot:

I don't know what triggers it. Most of the time it doesn't respond, but there is one specific US Highway 50 sign that triggers the car *every* *time*. I need to perhaps look at it more broadly to see if there's another sign or something in the periphery...

I'm guessing there's at least a minimum sanity filter that prevents strange results, but perhaps "50" is just one of those that won't be easily dealt with. Time to get out my paint again and turn some 35's into 85's.

 

[Brian J.]

I was driving north on I-295 in Rhode Island just before getting on I-95 north and was surprised to see that the little speed limit sign on the dash read 85. Haven't been back through there since to see if the problem replicates itself.