FSD Beta 11.3.6 does not understand rural road speed limits

[philw1776]

As others have said, it will NEVER do this because these are only suggestions. The car will use its vision and map knowledge to judge an appropriate speed for these situations.

Bad tactic as the car suddenly brakes and swerves going around corners way too fast. Jumps out of auto drive if a car suddenly appears incoming. Not good. Why can't it "use its vision" to decide maybe I should consider slowing down?

 

[KArnold]

Bad tactic as the car suddenly brakes and swerves going around corners way too fast.

Under what conditions does your car swerve? Do you mean lane position or lane change or something else?

 

[philw1776]

It swerves to make the sharp blind turn. context is reading yellow "suggested" speed limit reduction signs.

 

[enemji]

I know that New York and Vermont work this way (or variations of it), and I'm sure other states have variations of it. I got my original driver's license in New York, and we were taught that the State Speed Limit was 55mph unless otherwise posted (in Vermont it's 50mph). So if you don't see a speed limit sign instructing otherwise, you can assume the speed limit is 55mph. And like Washington, when you come out of a reduced speed zone, you see a sign that says "END 30 SPEED ZONE". I suppose this gives them the flexibility to change the state speed limit to something else (not that they've ever done that during my lifetime). And it also has the advantage that they don't have to post speed limit signs at intervals along country roads.

Most 55mph zones are indicated with signs that say "STATE SPEED LIMIT 55" (not just SPEED LIMIT 55) so you are reminded quite frequently what the default speed limit is. Maybe it's because I grew up there, but I don't think it's that confusing to know that when you come out of a town with a lower speed limit that the limit reverts to 55. But yeah, it is strange that they don't just post the new speed limit on the sign. I guess it's a throwback.

And yes, Tesla does not handle this at all. It will happily plod along for tens of miles on a back country road at 30 mph because it didn't see a new speed limit sign, and it apparently now exclusively uses signs to change speed as opposed to speed limits in its map data. Just one more reason that universal robotaxis are not coming any time soon.

Tesla uses the navigational data for speed limits, not signs. Signs are secondary.

 

[philw1776]

Not a good philosophy

 

[RTPEV]

Tesla uses the navigational data for speed limits, not signs. Signs are secondary.

Then either it's an FSD vs. non-FSD thing, or this is not true everywhere. I traveled for nearly 20 miles on a rural road in northern New York where the only speed limit marking was one of the "END 30 ZONE" types (meaning the limit reverted to 55) and the entire time the car thought the limit was 30.

 

[jabloomf1230]

Then either it's an FSD vs. non-FSD thing, or this is not true everywhere. I traveled for nearly 20 miles on a rural road in northern New York where the only speed limit marking was one of the "END 30 ZONE" types (meaning the limit reverted to 55) and the entire time the car thought the limit was 30.

Where was this? I'll look it up and let you know what the navigation database has, at least the OSM and Tomtom versions

 

[RTPEV]

Where was this? I'll look it up and let you know what the navigation database has, at least the OSM and Tomtom versions

County Rd 22 and County Rd 25 (which turns into County Rd 10 when you cross into St. Lawrence County) between Theresa & Macomb, NY

 

[jabloomf1230]

County Rd 22 and County Rd 25 (which turns into County Rd 10 when you cross into St. Lawrence County) between Theresa & Macomb, NY

In OSM, none of those roads have nodes with a speed limit tag. It would be a lot of work to add that tag manually to so many nodes. You could send fsdbeta at tesla dot com an email pointing out that where there are no explicit speed limits, county roads have the NY State speed limit of 55 mph.

TomTom, which uses a lot of OSM data, has a speed limit of 55 mph for all those county roads, so Tomtom must have added the default State speed limit for county highways without speed limits.

 

[enemji]

Then either it's an FSD vs. non-FSD thing, or this is not true everywhere. I traveled for nearly 20 miles on a rural road in northern New York where the only speed limit marking was one of the "END 30 ZONE" types (meaning the limit reverted to 55) and the entire time the car thought the limit was 30.

On non FSD cars, driving on non highways the speed does not automatically change. Sadly.

 

[melmalinowski]

As has been stated END 30 ZONE are non-standard signs.
Yep, the car doesn't recognize the stupid variable speed signs. Something that some idiot in DOT came up with. We have them here in Atlanta as well. And they are stupid.
But they aren't a problem for the car. When they change the speed from 65 to 55mph, that car tends to handle it well. Why? That's because they decreased the speed to match the fact that cars couldn't go that fast. Again it's a stupid concept and waste of money.

Different states do different things. Some states do stupid things. For example, a number of times I've gone to Seattle from Sea-Tac. I get in the HOV lane, but want to exit it. I drive for miles and there is NEVER a change from solid white to dotted white line to my right. That's when I figured out that in Washington, it's okay to cross a solid white line. That's not the case in most every other state.
Here in Georgia, it's very specifically illegal to cross the white line to get out of the HOV lane.

USDOT has standards. Most of them are just obvious conventions. But some states decide to buck a simple convention. USDOT tends to use federal funding as their only carrot to keep the states inline. But too much politics has entered the USDOT these days and things are just getting messed up,

/off soapbox

The joke among engineers: "The great thing about standards is that there are so many to choose among!" If we hope to have FSD, a set of federal road marking and signage standards would be a very good idea, and both greatly reduce the complexity that programmers have to cope with, and also improve safety for visitors driving around the country.

 

[melmalinowski]

So yes Tesla doesn't understand an End of 35mph sign, just like I don't understand it. It's definitely not a standard marking unless a construction zone.
Yes, Tesla understands rural road speeds, but it doesn't know the State Speed limit law. That's because the map has the speeds marked and that's it's primary source of speed limit information. So yes, it seems as if the map info may be wrong, it is in many locations.

You are probably right on a 90 degree turn, that's an extreme that I haven't seen the car do extremely well at.
BUT, the car does see most curves and does slow down for them, often a little too slow for my preference. (It didn't do this years ago, car would just freak)
And no, it does not recognize the yellow speed limit signs. If you watch the display, they will not appear, whereas the white ones will. In my years of experience, the caution speeds are close to being a joke in most locations, as in "25 mph" for a turn that is safely navigated at 45.

While some (maybe most) have statewide "if not marked" speed limits, they aren't a great idea. How am I as a visitor supposed to know it. Especially when they ARE DIFFERENT in different states.

Perhaps your area is different than ours. If the default speed is 50, and you approach a corner with a 25mph suggested speed and take it at 45, you'll run off the road into a fir tree, especially if there is any loose gravel or the pavement is wet. 25mph is usually a 90° curve. We even have some 15 mph switchbacks. Usually, you can exceed the recommended speed by 5-10 mph if you have a car that corners very well, as Teslas do. However, I feel very uncomfortable relying on FSD Beta to steer these corners at high speeds on a two lane rural road with F250s and log trucks coming at you head on. Not a good time to hope there is not a surprise sudden FSD suspension!

 

[legendsk]

Where was this? I'll look it up and let you know what the navigation database has, at least the OSM and Tomtom versions

Texas, Hidalgo county. Highway 2812 (E/W), between highway 493 (N/S) and highway 281 (N/S).
There are signs that the speed limit is sometimes 60 mph and sometimes 65 mph. Out in the middle of nowhere the car will suddenly slow down rapidly and indicate the speed limit is 25 mph, not a big deal, just hit the accelerator and keep it up at 65. But in a few minutes it will suddenly change the speed limit to 75, then perhaps 55, back to 25 for 1/2 mile. It's rather like the nav data believes there are school zones, etc., but there are not. I would love to know what the actual nav data shows.

I believe in a related way, the dash display shows exactly where the car is parked - correctly, I might add. However there is no possible way I have found to make that the 'Home' or 'Work' location. Those are both defined with a "mailing street address" which the car believes are somewhere else up to a mile away. Somehow the Charge Stats seems to deal with this, kind of, because it accurately records my charging at home, but has never recorded a "work" charging session?????

 

[philw1776]

I've tried for years to get my Tesla app to show my correct home street, town and house number to no avail. Puzzling because it shows the correct house on the map.

 

[jabloomf1230]

Texas, Hidalgo county. Highway 2812 (E/W), between highway 493 (N/S) and highway 281 (N/S).
There are signs that the speed limit is sometimes 60 mph and sometimes 65 mph. Out in the middle of nowhere the car will suddenly slow down rapidly and indicate the speed limit is 25 mph, not a big deal, just hit the accelerator and keep it up at 65. But in a few minutes it will suddenly change the speed limit to 75, then perhaps 55, back to 25 for 1/2 mile. It's rather like the nav data believes there are school zones, etc., but there are not. I would love to know what the actual nav data shows.

I believe in a related way, the dash display shows exactly where the car is parked - correctly, I might add. However there is no possible way I have found to make that the 'Home' or 'Work' location. Those are both defined with a "mailing street address" which the car believes are somewhere else up to a mile away. Somehow the Charge Stats seems to deal with this, kind of, because it accurately records my charging at home, but has never recorded a "work" charging session?????

FM 2812 has no speed limit tags on OSM. Tomtom has the speed limit for almost all nodes at 60 mph. The exception is the curved node west of Brushline Rd. This node of FM2812 does not have a speed limit tag.

 

[ewoodrick]

Perhaps your area is different than ours. If the default speed is 50, and you approach a corner with a 25mph suggested speed and take it at 45, you'll run off the road into a fir tree, especially if there is any loose gravel or the pavement is wet. 25mph is usually a 90° curve. We even have some 15 mph switchbacks. Usually, you can exceed the recommended speed by 5-10 mph if you have a car that corners very well, as Teslas do. However, I feel very uncomfortable relying on FSD Beta to steer these corners at high speeds on a two lane rural road with F250s and log trucks coming at you head on. Not a good time to hope there is not a surprise sudden FSD suspension!

I'll agree that our areas can be different. I know that in the Seattle area, the HOV lines are solid white it is expected that people cross a solid white line to get out of the HOV lane. In most of the rest of the country, you should never normally cross a solid white line. That's why they make dotted white entrances and exists.
But I have driven rural roads in many parts of the country and most all of the warning signs that I have seen are way too slow.

I'll also tell you that I worked an SCCA road rally years ago on dirt/rock forestry roads that were normally limited to 25 mph. That's because they had 180 degree turns that were effectively hairpins. The rally cars drove it at an AVERAGE of 60+ mph.


So many turns are in the eyes of the beholder. I know that you feel safe and you should only take the curve at the speed you feel safe at.
But your safe and mine, may not be the same.

BUT, most importantly, the yellow warning signs are warning signs. If the speed limit did indeed need to be decreased to save lives, they could easily make them a white sign.

 

[RTPEV]

I'll also tell you that I worked an SCCA road rally years ago on dirt/rock forestry roads that were normally limited to 25 mph. That's because they had 180 degree turns that were effectively hairpins. The rally cars drove it at an AVERAGE of 60+ mph.

I did John Buffum's Vermont Winter Rally for two years (won our class the first year). He took advantage of the fact that unmarked roads in Vermont were 50mph limits. So he would route us on those back roads with a CAS in the high 40's (this was an overnight rally, so really no traffic expected), and as you can imagine, actual speeds were quite a bit higher to make up for the occasional slowdown.

After the second year I decided that my stomach couldn't take it any more (possibly would have been different if I was driving instead of navigating).

 

[sleepydoc]

What speed limits shows up in your apple & google maps?

With either 11.4.2 or 11.3.6 FSDb changed the way it handled speed limits and map data. Prior to this it seemed to read the signs but then default to the limit from the map data at the next node on the map. Now it seems to rely almost exclusively on signs. This may be the source of the OP’s problem - if there’s no sign it won’t change.

I have to agree with @Supcom - If you’re putting up a sign anyway, why not just post the speed limit instead of something much less clear?

 

[BitJam]

With either 11.4.2 or 11.3.6 FSDb changed the way it handled speed limits and map data. Prior to this it seemed to read the signs but then default to the limit from the map data at the next node on the map. Now it seems to rely almost exclusively on signs. This may be the source of the OP’s problem - if there’s no sign it won’t change.

That is not my experience. My car will change what it thinks is the speed limit with no signs. This started happening (or happening more) when I upgraded from AP to FSD 11.3.6.

I have to agree with @Supcom - If you’re putting up a sign anyway, why not just post the speed limit instead of something much less clear?

One reason would be to give them the flexibility to change the default speed limit without having to change a bunch of signs.

 

[philw1776]

Latest Beta is a great improvement...
However it still misses several suburban regular white with black letter speed limit signs. Dunno why.
Also if a STOP sign on a perpendicular road is not fully 90+ degrees angled an it can "see" it, the car stops, seems to realize its error and continues. On a 35 or 40 MPH thru road this is a bad thing. Obviously I don't let it have its way if someone is behind me.