Model S

Can the Tesla Autopilot be Set to Obey Speed Limits?

edited November -1 in Model S
A few years ago we put down a deposit on a Tesla Model S (Pre-autopilot).

I've seen now systems in Europe that can actually read the speed limit signs and react.
Is that on the Autopilot? Or is there some sort of GPS based system?

(We put down a deposit years ago but when my mother drove it the big screen sort of overwhelmed her.)
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Comments

  • edited November -1
    Yes - you can set the Traffic Aware Cruise Control to x miles per hour over the speed limit. The does both - it uses GPS data and the camera to read the speed limit signs. You know it has a lock on the speed limit when the little speed limit sign appears to the left of the speedometer.
  • edited November -1
    What is the process for setting that? I've never managed to do that.

    On smaller roads, Autopilot is limited to 5mph over the limit (in the USA, at least), but if you take over steering, it suddenly jumps the speed back to whatever you had it set to, which isn't quite safe.
  • edited November -1
    Note: The GPS data is often wrong, or outdated. having it self adjust the idea of the speed limit could be dangerous. (PA Turnpike is 70MPH now, GPS data in Tesla still has it as 65).

    Depending on camera read signs is also dangerous. I've been in many areas where mis reads the sign and says the limit is 15MPH while I am on a superhighway. I've also made turns off a 55MPH road to a road that is 25MPH and it doesn't see a sign and just leaves up the 55MPH on the dash. Depending on the driver is better, even if they want to speed, at least it was their decision and they can't blame the car.
  • edited July 2016
    Why would you want to do that?
  • edited November -1
    @exchaoordo

    Tesla's autopilot is CAPABLE of reading+adhering to speed limit signs, however, the current implementation does NOT have that feature turned on. The initial Autopilot live demo did have this feature turned on and they demonstrated how the car would slow or speed up based on the speed limit sign.

    Currently the car will absolutely read the signs and if you have yet to engage Autopilot it will prep your speed to the speed limit or your determined offset from the speed limit (Speed limit + [X]mph) so when you do engage AP it starts there, but it does NOT automatically conform to the signs right now.
  • edited November -1
    Camera can't read the yellow speed limit signs as well
  • edited November -1
    I have seen signs misread as 5 mph and 95 mph in a 35 mph zone. No way do I want that implemented automatically.
  • JADJAD
    edited November -1
    It already does sometimes. Highway 395 is mostly a double lane divided highway, you set your speed whatever you want, but as you approach towns it becomes an undivided road and Tesla limits to +5 on the speed limit. Thus the car automatically allows to 25 mph for the towns, then back to speed as you leave. It is not fully autonomous, so of course i monitor it in case it is wrong, or too much is happening in the town but very nice how it follows the signs. Not sure why only on undivided roads though.
  • edited July 2016
    @JAD

    Thats actually not accurate, the car slows down on roads deemed "Autosteer Restricted" which is GPS-based not based on the speed limit sign. Also not all town locations/roads are actively marked as "Autosteer Restricted" so there are plenty of places where this isnt applicable its still a work in progress.
  • JADJAD
    edited July 2016
    @jlewisthe3rd, we are both correct, by definition, undivided highways are autosteer restricted, which is why it follows the speed limit signs and goes a maximum of 5 mph over the posted speed limit through the town.

    On the 395, the general speed limit is 65 mph, so I usually set AP at 75. As I approach the town, the speed limit drops to 55 mph, so the car slows to 60 mph, then there are signs for 45, 35, 25 mph. At each sign, the speed drops to +5 over that and then resumes at the other end of town.

    It would be nice for this to work on ALL roads, not just undivided/restricted roads.
  • edited November -1
    @JAD - Agreed with Autosteer restriction (AR) following speed signs AFTER AR is engaged (dropping in speed based on signs) but again AR is triggered by GPS and not speed limit signs, and again not all undivided streets, or highways are AR-mapped so its an incomplete implementation IMO.

    Definitely wish it was a setting that could be turned on and off to allow for seamless driving on the highway. Got a speeding ticket in the DC area because the limit changed and AP did not adjust.
  • edited November -1
    The specification when for the AP decides to auto-limit speed to 5 over is not divided versus non divided - that is one criteria, but the system will allow unlimited speeds (up to 90) even on non-limited access highways where the speed limit is 55 or higher. However, when the limit drops to below 55 on such a highway, the system begins to limit speed to 5 over the new limit.

    Unfortunately the system does not work well enough because it is often quite slow in processing the new lower limit. For example, when I drive on Rt. 50 or 13 in Maryland and Virginia, both divided but not limited access highways (they have at-grade crossovers and traffic signals, but are predominately 55 mph roads with sections reduced to 45) and the limit drops from 55 to 45. it can take several hundred yards for the new lower limit to kick in, and the car begins to slow. I have to over-ride in this situation, as I keep the system set at 10 over, so it is running along on AP at 65, hits the new 45 limit, and then a few hundred yards later, automatically lowers the car's speed to 50 miles per hour. That leaves my car temporarily running at 15 over the actual limit. As these areas are police speed traps, AP would expose me to being cited. Instead, I press the AP stalk fully down two times, and the car goes to 55 mph, 10 over the new limit (police allow 10 mph over the limit in this area before citing).

    AP generally does a good job reading signs in my experience, but cannot handle exceptions. For example, it reads the 15 mph limit on my mile-long farm road, a sign that I personally installed, so clearly not from a GPS database. On the other hand, most of our rural roads in the eastern shore area of Virginia have signs that say "End of 35 limit" at the town line, and the speed limit, by state law, goes automatically to 55. However, there are no 55 speed limit signs on those roads, and the car simply stays at 35, even though the lower limit has ended. This is the kind of localized anomaly that makes AP implementation exceedingly difficult.
  • edited November -1
    @jlewisthe3rd "Thats actually not accurate, the car slows down on roads deemed "Autosteer Restricted" which is GPS-based not based on the speed limit sign. Also not all town locations/roads are actively marked as "Autosteer Restricted" so there are plenty of places where this isnt applicable its still a work in progress."

    @JAD "@jlewisthe3rd, we are both correct, by definition, undivided highways are autosteer restricted, which is why it follows the speed limit signs and goes a maximum of 5 mph over the posted speed limit through the town."

    You are both incorrect. Autosteer can produce restricted speeds on a single divided highway and no restrictions at other places on the same divided highway. It is speed-limit-dependent. When the speed limit is 55 or higher, it will never limit the speed, even on divided highways that are not limited access. When the limit drops below 55, the autosteer 5-over limit kicks in, although usually delayed as I described above. Clearly a work in process.
  • edited July 2016
    @Pungoteague_Dave - I was hoping that by you saying we were both incorrect you'd bring a POV that contradicts the both of us, but you're simply restating what I already said.

    It doesnt matter whether the road is divided or undivided, single lane or multiple lane. The Autosteer Restriction (AR) is based on a mapping system that Tesla uses to determine which Geolocated roads are deemed as "Restricted" and what their restricted speeds are. It is NOT dependent on the speed limit sign but Geo location and not all roads or portions of roads are mapped so can often have a situation where you are on the same road and part of it is restricted and others are not, and it also doesnt matter if you are 55mph+ or not it just so happens that MOST of the restricted roads are what are considered "Residential" with speed limits at 45mph. We will see more of these roads come into play over time.

    Also to note I've had the pleasure of driving/riding AP all over the country and tested just about every type of road with it, so my perspective and knowledge is not limited to just one geographic region.
  • JADJAD
    edited November -1
    How do you know that it is GPS based, and not reading the signs? Tesla claims it can use both methods?

    I was trying to answer the OP's question, currently, the car does adjust speed based on speed limit, but only under certain conditions. I would guess it will be updated to work under more conditions 'soon', as the required hardware is present and partially functioning.
  • edited July 2016
    @JAD- I've seen the AR kick in on many roads where speed limit signs were nowhere to be found. Additionally, GPS is the only way the car knows where it is, to know that a road or section of a road is "Restricted" those restricted roads are stored as geolocation areas on the map that is then relayed to the car when it hits those coordinates.

    The car camera does read speed limit signs but they do not register until the car passes a sign, try it out and see for yourself.
  • edited November -1
    Essentially we weren't quite given what we were promised, what was promised wouldn't necessarily be suitable if there are areas where the car can't tell speed limits correctly, and the car does implement this under some circumstances, as others have pointed out. In general, when the speed limit changes, it means that pulling the lever toward you for about two seconds will readjust it to the new speed limit. You can set the car so it annoys you with a beep if you exceed the speed limit or your threshold above it, so it would be hard to do it by accident in any situation where the car knows your speed limit.

    That being said, I'd like to see a user configurable option that lets a driver decide that the logic used on divided roads should stay in effect even when autosteer is off and that leaves it in effect on all roads. After all, it's what Tesla promised us in the first place, and making it configurable won't hurt anybody who doesn't want that or who lives in an area without accurate/relevant/frequent enough speed limit signs.
  • edited July 2016
    @JAD, PD is the self-professed expert on Tesla's corporate operations, finance, and product safety.
  • edited November -1
    PD is sometimes (always?) strongly opinionated but he is knowledgeable and intelligent. He's not making this stuff up. I don't always agree with him, and he probably doesn't agree with everything I say, but I bet he has more business experience than 95% of the people here. I don't think I'd give him a job as a diplomat though.

    By the way, "end [of] 35 [MPH/speed] limit" isn't a local anomaly. All states have prima facie speed limits that apply based on the type of road. I can't say how many of them have "end" signs without explicit signs stating the effective speed limit, but certainly the majority of Tesla's cars in the US are in states that do things that way. There are all sorts of things like this that Tesla doesn't account for.
  • edited July 2016
    MY Car reads the sign and reduce the speeds in highways allows upto 20km/h over the limit and in local highways where below 100km/h speed limit allow 10km/h over the posted limits, and below 40km/h it allow 5km/h over the posted limits.
    But I could not find a way to set up to follow the exact speed of the sign.
  • edited November -1
    @Haggy, I don't disagree that PD is knowledgeable and intelligent. I also don't disagree he's opinionated.

    But he can still be wrong. And he is.
  • edited July 2016
    It's a complex system and a lot of things are used in different places. I know it reads most speed limit signs very well and adjusts instantly. I've seen situations with roads where the car didn't necessarily impose the rules I expected. I know of places where the car will not only slow down for curves but will also actively change the speed limit displayed for the particular curve even though there's no sign, and then bump the limit back up, even though there's no sign. That part might not be done as a rule and might be only because it's an undivided highway that's commonly used on a trip from the Bay Area to SoCal. For those who drive on routes that Elon doesn't take, there might be different rules.
  • edited November -1
    The algorithms need a bit of refinement before letting it set the speed automatically will be really safe to use. On PA route 100, it had a problem with the signage twice, resulting in this within a 50 MPH zone:
    <img src="https://flic.kr/p/JTSrnb&quot; width="600">
  • edited November -1
    Bother. Trying again.
    <img src="https://www.flickr.com/photos/[email protected]/28153966480/&quot; width="600">
  • edited November -1
    <img src="http://i.imgur.com/zb91smU.jpg&quot; width="600">
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