# Reading speed limit signs



## SR22pilot (Aug 16, 2018)

FRC said:


> Considering the inaccuracy in mapping speed limits over the past three years, I can't imagine that mapping is the solution for traffic signals.


As best I can tell, Tesla isn't reading speed limit signs at all so the car isn't mapping that at all. This is a huge limitation. I wonder if there is a Mobileye patent issue.


----------



## garsh (Apr 4, 2016)

SR22pilot said:


> As best I can tell, Tesla isn't reading speed limit signs at all so the car isn't mapping that at all. This is a huge limitation. I wonder if there is a Mobileye patent issue.


That is *exactly* the problem.
https://patents.google.com/patent/US20080137908A1/en
Looks like we're stuck with this patent until 2031.


----------



## M3OC Rules (Nov 18, 2016)

garsh said:


> That is *exactly* the problem.
> https://patents.google.com/patent/US20080137908A1/en
> Looks like we're stuck with this patent until 2031.


Do you know any more on this? I haven't looked closely at them but I assume the Mobileye one is AI-based vs previous ones. Maybe they could license or get around it somehow? This one just expired: https://patents.google.com/patent/DE19852631C2/en


----------



## garsh (Apr 4, 2016)

M3OC Rules said:


> I haven't looked closely at them but I assume the Mobileye one is AI-based vs previous ones.


Mobileye mentions a classification system, but doesn't appear to actually state if it uses machine learning to create it.
I was just skimming the description though.


----------



## PaulT (Aug 22, 2018)

garsh said:


> That is *exactly* the problem.
> https://patents.google.com/patent/US20080137908A1/en
> Looks like we're stuck with this patent until 2031.


This was such a shortsighted approval by the patent office. I feel like a patent for the ability of AI to detect something is like putting a patent on the way someone thinks.


----------



## GDN (Oct 30, 2017)

PaulT said:


> This was such a shortsighted approval by the patent office. I feel like a patent for the ability of AI to detect something is like putting a patent on the way someone thinks.


I think you've hit the nail on the head with thousands of patents in recent years. There are tons of patents about how someone writes code. If a coding language is there and has constructs, etc - it should be open for all to use. But we have patents issues for how code is written and used. This is just one small example. Way too many patents have been issued to protect general ways of thinking.


----------



## SR22pilot (Aug 16, 2018)

GDN said:


> I think you've hit the nail on the head with thousands of patents in recent years. There are tons of patents about how someone writes code. If a coding language is there and has constructs, etc - it should be open for all to use. But we have patents issues for how code is written and used. This is just one small example. Way too many patents have been issued to protect general ways of thinking.


The patent office has little real insight. I had one patent denied because it was similar to another. However, that other patent was from the same company that I was employed by. It took two years to go from that older patent to mine and there was a very key difference. The patent office just couldn't grasp the difference.


----------



## francoisp (Sep 28, 2018)

garsh said:


> That is *exactly* the problem.
> https://patents.google.com/patent/US20080137908A1/en
> Looks like we're stuck with this patent until 2031.


Interesting. Based on the patent summary, I wonder how Tesla is able to get away with identifying traffic lights, stop signs and any other objects using its camera. I can't imagine Mobileye was shortsighted and forgot to patent the methods for handling those as well. Is it possible that Mobileye's patent be limited to the specific method described in the patent and that as long as Tesla uses a different one it should be fine?


----------



## DocScott (Mar 6, 2019)

FrancoisP said:


> Interesting. Based on the patent summary, I wonder how Tesla is able to get away with identifying traffic lights, stop signs and any other objects using its camera. I can't imagine Mobileye was shortsighted and forgot to patent the methods for handling those as well. Is it possible that Mobileye's patent be limited to the specific method described in the patent and that as long as Tesla uses a different one it should be fine?


Good point.

Thinking that patenting "a method for detecting and identifying a traffic sign in a computerized system mounted on a moving vehicle" is the same as patenting _all_ methods for detecting and identifying a traffic sign in a computerized system mounted on a moving vehicle would be like thinking that patenting _a_ mousetrap is the same as patenting _all_ mousetraps.


----------



## garsh (Apr 4, 2016)

FrancoisP said:


> Interesting. Based on the patent summary, I wonder how Tesla is able to get away with identifying traffic lights, stop signs and any other objects using its camera.


Under *FIELD OF THE INVENTION*, the patent says:
_"The present invention relates to driver assistance systems in motorized vehicles."_

That may be the key difference. If you display the speed limit information to the driver, then it's being used for "driver assistance". If you only use the information to implement full-self-driving and are careful not to display it to a driver, then it's not in the field of "driver assistance", and therefore not covered by this patent.

I am not a patent lawyer. This is just a guess.


----------



## M3OC Rules (Nov 18, 2016)

DocScott said:


> Good point.
> 
> Thinking that patenting "a method for detecting and identifying a traffic sign in a computerized system mounted on a moving vehicle" is the same as patenting _all_ methods for detecting and identifying a traffic sign in a computerized system mounted on a moving vehicle would be like thinking that patenting _a_ mousetrap is the same as patenting _all_ mousetraps.


Yes. Mobileye didn't invent detecting traffic signs with cameras on cars and that patent has expired. Looking at the claims here it looks like this is the main part as described in the abstract "The image frames are partitioned into the image processor into a first portion of the image frames for the detection of the traffic sign and into a second portion of the image frames for the other driver assistance function. Upon detecting an image suspected to be of the traffic sign in at least one of said image frames of the first portion, the image is tracked in at least one of the image frames of the second portion."

Without knowing too much about this, it doesn't seem like something fundamental that can't be worked around.


----------



## garsh (Apr 4, 2016)

Apparently, this is either not patent-encumbered, or Tesla created a new method of reading signs that circumvents the patent.


__ https://twitter.com/i/web/status/1258669984483430400


----------



## bwilson4web (Mar 4, 2019)

I had to do my quarterly BMW i3-REx run-about and reading speed signs is the only trick I wish my Model 3 could do. Just curious, did the 'Magiceye', early Teslas read speed signs?

Bob Wilson


----------



## garsh (Apr 4, 2016)

bwilson4web said:


> I had to do my quarterly BMW i3-REx run-about and reading speed signs is the only trick I wish my Model 3 could do. Just curious, did the 'Magiceye', early Teslas read speed signs?


Yes, the first Tesla AP cars with Mobileye hardware would read speed limit signs.


----------



## Garlan Garner (May 24, 2016)

How would anyone know if Tesla is reading signs or not. 

In other words....If Tesla's cameras are reading the signs and displaying the speed on the screen....then autopilot follows the display on the screen...then how would anyone know? 

IMHO....Tesla does not have to display the actual shape and design of the Sign for autopilot to work....or for its customers to be happy.


----------



## iChris93 (Feb 3, 2017)

Garlan Garner said:


> How would anyone know if Tesla is reading signs or not.
> 
> In other words....If Tesla's cameras are reading the signs and displaying the speed on the screen....then autopilot follows the display on the screen...then how would anyone know?
> 
> IMHO....Tesla does not have to display the actual shape and design of the Sign for autopilot to work....or for its customers to be happy.


We know that it is not reacting to the signs, at least, because often the displayed value is not the correct signed limit. That means the displayed value is coming from incorrect map data.


----------



## garsh (Apr 4, 2016)

Garlan Garner said:


> How would anyone know if Tesla is reading signs or not.


Hold up a sign with a different speed limit in front of a real speed limit sign.

See which limit the car reports when it drives by.


----------



## Garlan Garner (May 24, 2016)

iChris93 said:


> We know that it is not reacting to the signs, at least, because often the displayed value is not the correct signed limit. That means the displayed value is coming from incorrect map data.


I was hoping that Tesla was smushing in some incorrect numbers from time to time....in order to throw everyone off the scent of violating a patent.

Just kidding. LOL.


----------



## michigantesla (Mar 9, 2019)

There are a lot of edge cases even when reading signs. The speed limit sign pictured is right outside my office. In Michigan this signs means that the specified limit is ending and the new limit is the state default - 55. Sure enough my M3 thinks this section is 45 MPH which is useless for auto steer. I imagine there are many cases like this. The best option to get correct data may be like what Waze uses - user reports with map editor oversight.


----------



## Garlan Garner (May 24, 2016)

michigantesla said:


> There are a lot of edge cases even when reading signs. The speed limit sign pictured is right outside my office. In Michigan this signs means that the specified limit is ending and the new limit is the state default - 55. Sure enough my M3 thinks this section is 45 MPH which is useless for auto steer. I imagine there are many cases like this. The best option to get correct data may be like what Waze uses - user reports with map editor oversight.
> View attachment 33951


That's an illegal US highway sign.

States/Municipalities are ONLY supposed to display signs that display positives. That sign is supposed to display what the actual speed is....not what its not. <------hmmmm does that make sense?

In other words.....all that sign says is that there was a previous speed limit of 45....and now its not. Thats illegal.

NOW....that said....there is a pending project that Tesla received in Illinois under Gov. Pritsker. He wants Illinois to pay Tesla to provide the state of Illinois with illegal signs and road markings and pothole information instead of hiring a crew of xxx to do it.

I would have to say that his 9 figure per year offer is something Tesla might want to look at in every state. Especially since Tesla has the data. It would only have to be parsed with programming at this point. I mean.....how would us owners know? Might be a comfortable extra 50 billion billion a year....


----------



## iChris93 (Feb 3, 2017)

michigantesla said:


> In Michigan this signs means that the specified limit is ending and the new limit is the state default - 55.


I've seen these around and never knew what the speed limit past the sign was. Thanks for the info!


----------



## MelindaV (Apr 2, 2016)

Garlan Garner said:


> How would anyone know if Tesla is reading signs or not.
> 
> In other words....If Tesla's cameras are reading the signs and displaying the speed on the screen....then autopilot follows the display on the screen...then how would anyone know?
> 
> IMHO....Tesla does not have to display the actual shape and design of the Sign for autopilot to work....or for its customers to be happy.


my work commute (when I was working in the office), included passing a 50MPH sign. For the last 18 months it has registered this 1 mile section of freeway at 70MPH (which there is is not an area within 30+ miles with the 70 mph limit)


----------



## FRC (Aug 4, 2018)

michigantesla said:


> There are a lot of edge cases even when reading signs. The speed limit sign pictured is right outside my office. In Michigan this signs means that the specified limit is ending and the new limit is the state default - 55. Sure enough my M3 thinks this section is 45 MPH which is useless for auto steer. I imagine there are many cases like this. The best option to get correct data may be like what Waze uses - user reports with map editor oversight.
> View attachment 33951


OK Michigan, I gotta ask. Legal or illegal, what's the point of this road sign? As @iChris93 says, he never knew what it meant. Why not just post the 55 sign? Is it somehow cheaper/easier/ more informative to post the 45 ends sign? Makes absolutely no sense to me.


----------



## NickJonesS71 (May 11, 2020)

FRC said:


> Is it somehow cheaper/easier/ more informative to post the 45 ends sign? Makes absolutely no sense to me.


For the sake of cost. You'd think they might just change the first digit? And save the use of the second sign below all together?


----------



## garsh (Apr 4, 2016)

FRC said:


> OK Michigan, I gotta ask. Legal or illegal, what's the point of this road sign? As @iChris93 says, he never knew what it meant. Why not just post the 55 sign? Is it somehow cheaper/easier/ more informative to post the 45 ends sign? Makes absolutely no sense to me.


We have the same signs in PA.

Roads that don't have signs default to the... well, "default" state speed limit, 55mph. That way the majority of two-lane highways don't need any speed limit signs at all, saving money. Then when you get close to a town, you'll start seeing speed limit signs. When you leave a town, you'll see a final sign that says "end" speed limit, and you're back at the default speed limit again.


----------



## FRC (Aug 4, 2018)

garsh said:


> We have the same signs in PA.
> 
> Roads that don't have signs default to the... well, "default" state speed limit, 55mph. That way the majority of two-lane highways don't need any speed limit signs at all, saving money. Then when you get close to a town, you'll start seeing speed limit signs. When you leave a town, you'll see a final sign that says "end" speed limit, and you're back at the default speed limit again.


But at the end of the reduced speed limit zone, doesn't a normal speed limit 55 sign serve the same purpose for less cost? That, BTW, is how most of America does it.


----------



## garsh (Apr 4, 2016)

FRC said:


> But at the end of the reduced speed limit zone, doesn't a normal speed limit 55 sign serve the same purpose for less cost? That, BTW, is how most of America does it.


It does, until the state decides to change their default speed limit, then it doesn't. But that doesn't happen often.

I don't know how any state expects out-of-state drivers to know what the defaults are. I'm guessing that this is all hold-over from MUCH earlier times before everybody put money into maintaining good roads.


----------



## iChris93 (Feb 3, 2017)

garsh said:


> MUCH earlier times before everybody put money into maintaining good roads.


Michigan must still be in earlier times.


----------



## mrau (Nov 22, 2018)

I believe the "Speed Limit Ends" signs are used in local city/villages only. Usually on roads that pass through their jurisdiction where they have lowered the county speed limit on. Since the local jurisdiction can not set the speed limit on the road (or place a sign setting the Speed Limit) once the road leaves their jurisdiction, they can only place a sign that ENDS their reduce speed area. The "Speed Limit Ends" placement may be at the city/village border or anywhere else inside their border where they wanted the reduced speed to end.

With more self driving and AI cars, maybe they will change their ways and only show what the Speed Limit is, not what it was.


----------



## michigantesla (Mar 9, 2019)

FRC said:


> OK Michigan, I gotta ask. Legal or illegal, what's the point of this road sign? As @iChris93 says, he never knew what it meant. Why not just post the 55 sign? Is it somehow cheaper/easier/ more informative to post the 45 ends sign? Makes absolutely no sense to me.


I have no idea why they do this in Michigan. But around me there are several instances of this. There are also unposted roads in Michigan (especially in the Upper Peninsula) where the speed limit is also the default of 55. Another fun fact: unposted gravel roads (which are all over) are generally unposted outside of Wayne and Oakland county. These are also 55MPH. Funny even though these gravel roads are unposted, most drivers will drive slower because that is the safe speed to drive. Before anyone goes racing around the gravel roads  it should be pointed out that you can receive a ticket for driving too fast for conditions - regardless of the speed limit.


----------

