[Talk-ca] Telenav mapping turn restrictions

Andrew Lester a-lester at shaw.ca
Sun Mar 26 15:40:39 UTC 2017


Thanks for the input. The Motor Vehicle Act is written in legalese and therefore hard to decipher, but I think you've raised enough points that I'm going to look into it further. I had already removed some of the right turn restrictions, but I can add them back in if I determine that such turns are indeed illegal. I don't see people make these turns very often. It's usually only if someone has stopped at the red light waiting to go through or turn left, but then changes their mind and turns right instead. I always had the understanding that it was legal to do so, but I may have been led astray. I'll see if I can consult someone familiar with BC's driving laws and I'll report back here so other mappers will know too. 

There's still the matter of armchair mapping wiping out on-the-ground mapping. This is something that always happens occasionally, and I can live with the occasional instance, but the volume of mapping being undertaken by Telenav means this is now happening too often to be acceptable. Their mappers need to be given more guidance about what to do and what not to do. 

Andrew 


From: "Ian Bruseker" <ian.bruseker at gmail.com> 
To: "a-lester" <a-lester at shaw.ca> 
Cc: "James" <james2432 at gmail.com>, "talk-ca" <talk-ca at openstreetmap.org> 
Sent: Saturday, March 25, 2017 11:05:53 PM 
Subject: Re: [Talk-ca] Telenav mapping turn restrictions 

Andrew, 
I'm sorry to butt in here, I'm normally just a lurker and occasional editor of my local bit of the world in OSM, but your comment on the right hand turn restriction "at least in BC" really jumped out at me. I've seen a number of times in my driving life someone do exactly what you are describing, turning right at the actual intersection of two roads, rather than the turning lane that came a little earlier, and every time they have had BC plates. I live in Alberta, so I just shrugged it off as "they're tourists, they just realized they missed their turn, whatever". :-) But based on your comment, maybe this is a "BC thing" and you all do it. ;-) 

It's always seemed weird to me to see it (but like I said, "tourists, whatever"), and seems like a really unsafe and really should be illegal practice. Imagine this scenario: driver A is traveling down Wilfert, as from your map, and appears to be headed straight through the intersection. Driver B behind them takes the right-turn linking lane to get to Island Highway. Driver A suddenly decides they need to go right, so they turn at the intersection proper. Driver B, having seen the light was green for those going straight on Wilfert, presumes (always a bad idea, but hear me out) that no car could possibly be coming across their path and drives through the right lane and takes the corner. Then BOOM, driver A's car is there out of nowhere because he took the later option to turn right. Surely that must be illegal because it is so unsafe. Not to mention driver C behind both of them also expects driver A to go straight because driver A has already passed the turning lane, so doesn't expect drive A to suddenly decelerate for the turn (this is how I have come to be close enough to a car to see its BC plates, as I slam on the brakes to avoid hitting them). 

So I did a quick google. I am not, really really not, a lawyer, but my amateur reading of 151(e), as found here: http://www.bclaws.ca/civix/document/id/complete/statreg/96318_05#section151 , "when approaching an intersection intending to turn right must drive the vehicle in the lane nearest to the right hand side of the roadway", my take on the wording "must" drive, and lane "nearest" to the right, tells me that the linking lane is the only one that it is legal to make a right turn from. Also, section 165(4) ( http://www.bclaws.ca/civix/document/id/complete/statreg/96318_05#section165 ) says "If at an intersection there is a traffic control device indicating the course to be travelled by vehicles turning at the intersection, a driver must turn a vehicle at the intersection in the manner directed by the traffic control device.", and in the definitions section, it defines a traffic control device as "a sign, signal, line, meter, marking, space, barrier or device". Based on the satellite imagery of that intersection (never actually been there myself), it sure looks like there are "lines" and "spaces" and possibly even a concrete island "barrier" (imagery isn't that detailed, but sure looks like it) on the road that make it clear in where there is a place to turn right. Also again with the word "must" rather than something less imperative like "may" or "could". So based on my reading, it's not that the turn is legal unless otherwise indicated, as you say, but rather that it is illegal unless otherwise indicated to turn at exactly the spot marked, because you "must" follow the traffic control device indications, which is more than just signs, and those devices are indicating that you "must" take the linking lane. 

I totally accept that I'm being a major buttinsky here and probably coming off like a huge know-it-all, and I am SO sorry about that, but, given that whatever decision is made about whether this is right or not will live on in the map, I totally agree with what I think the spirit of what you're saying, which is "it needs to be correct". I just think that the "correct" thing is that you can't actually legally turn at that spot, just as that turn restriction edit indicates. If you got that far, go straight and find another way to your destination, or turn right and expect a ticket or an accident to happen. Any lawyers or police officers on this list? Their opinions are worth WAY more than mine. :-) Again, I am really really sorry to butt in. I just like "correctness" in the map, as you clearly do. I totally agree with the other half of your email, that having on-the-ground work killed by bad imagery traces is terrible. That's why I only edit places where I have actually put my own two feet on the ground. :-) 

Ian 


On 25 March 2017 at 21:52, Andrew Lester < a-lester at shaw.ca > wrote: 



I just discovered that user georges_telenav has been mapping turn restrictions in the Victoria, BC area. While some of them seem valid, there are hundreds of right-turn restrictions that can't possibly be based on either Mapillary or OpenStreetView as stated below, because these restrictions simply don't exist in reality. Here's an example: http://www.openstreetmap.org/relation/7014602 

I don't know about the rest of Canada, but at least in BC, this type of turn is perfectly legal unless otherwise indicated. Most drivers would use the link road and I'd expect routers should always prefer that, but there's nothing wrong if a driver gets past the link road and then changes their mind and wants to turn right. I can think of a handful of locations around town where there may be a sign explicitly forbidding this or at least implying it (e.g. "only left turn"), but the vast majority of the instances that this user has mapped do not have such signage. I'm in the process of cleaning all these up, but I'm worried there may be thousands more of these all over the place outside my immediate region. 

However, what I discovered while cleaning these up is even more disturbing. This is a region with significant growth, and there are frequent changes and additions to the road network. So far, I've discovered several cases where a reconfigured intersection or new road I had carefully mapped by GPS has been obliterated and replaced with an old configuration, apparently based on out-of-date aerial imagery. I take pride in mapping these changes as soon as possible after they're completed so end-users have the most reliable data (and I often mention this to people as one of the benefits of using OSM data in applications), so it's disappointing to see a distant armchair mapper destroy this careful on-the-ground work based on faulty assumptions and out-of-date imagery. I've also seen Telenav mappers adding residential roads that are clearly driveways and making edits without properly aligning aerial imagery, so I'm not exactly filled with confidence that they should be making widespread changes like they are. 

Martijn, I think Telenav needs to stop what they're doing and have a careful discussion with us about their plans and editing procedures before making any more edits. At least in my area, their edits have not only failed to improve the dataset, but in a number of cases has actually degraded it. Something needs to be done about this before things go too far. I already have a lot of cleanup work ahead of me, and I'd like to avoid this happening again in the future (at least by Telenav). 

Andrew 
Victoria, BC, Canada 


From: "James" < james2432 at gmail.com > 
To: "John Marshall" < rps333 at gmail.com > 
Cc: "talk-ca" < talk-ca at openstreetmap.org > 
Sent: Wednesday, October 19, 2016 11:44:53 AM 
Subject: Re: [Talk-ca] Telenav mapping turn restrictions 



Yeah no one really wants to do that, except maybe mapbox's india contractors 

On Oct 19, 2016 2:43 PM, "John Marshall" < rps333 at gmail.com > wrote: 

BQ_BEGIN

Make sense to me. A dding turn restrictions is something I don't want to add. 
Happy to see all my Mapillary and OpenStreetView imagery being used to help improve the map. 

John 

On Tue, Oct 18, 2016 at 9:24 AM, Begin Daniel < jfd553 at hotmail.com > wrote: 

BQ_BEGIN



Go with the recommended scheme as described on the wiki. 

Daniel 



From: Martijn van Exel [mailto: m at rtijn.org ] 
Sent: Monday, 17 October, 2016 23:53 
To: Talk-CA OpenStreetMap 
Subject: [Talk-ca] Telenav mapping turn restrictions 





Hi all, 





I wanted to give you a heads up that my colleagues on the Telenav map team are starting work on adding turn restrictions in Toronto, Montréal, and later on also Vancouver, Ottawa and Calgary. We are using OpenStreetView and Mapillary as sources. If you have any questions or concerns, please reach out to me and we will address it right away. 





For conditional (time-restricted) turn restrictions, we intend to use the schema described in http://wiki.openstreetmap.org/wiki/Conditional_restrictions . We encounter a more complex mapping of conditional turn restrictions sometimes, where mappers have used day_on / day_off and hour_on / hour_off. This is uncommon and as far as I know not recommended for mapping time-restricted turn restrictions. If we encounter these, our proposal would be to remove these tags and if necessary replace them with the preferred scheme as described on the wiki. Opinions? 





Best, 


Martijn 




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