How do SatNav (TomTom) traffic updates work?

[BanburyBlue]

I used to have a TomTom Go 720. I bought a traffic dongle where one end plugged into the SatNav and the other end, that was an aerial, was stuck to the inside of the windscreen. I think it was supposed to work by scanning local radio stations for local traffic news. Frankly it was pretty hit and miss and never really gave any useful information.

When that SatNav failed, I bought a TomTom Go Essential, which has inbuilt traffic alerts. The traffic alerts are far superior, and do mostly seem up to date. The traffic alerts show traffic jams on local/unclassified roads, as well as Motorways and Trunk Roads. I'm just wondering how it all works? Where does the data come from? How do TomTom know the road past my local Tesco has a traffic jam?

Thanks

 

[Doctor Fegg]

Devices feed back their current speed and location to the satnav companies. You'll find that your mobile phone regularly phones home to Google/Apple, for example, to say "I'm at lat 51.12387, lon -1.234876, and I'm going at 17mph". With enough reports like that, the company can find out the current traffic speed on that road.

And yes, it can be broken entertainingly - https://www.simonweckert.com/googlemapshacks.html

 

[BanburyBlue]

Devices feed back their current speed and location to the satnav companies. You'll find that your mobile phone regularly phones home to Google/Apple, for example, to say "I'm at lat 51.12387, lon -1.234876, and I'm going at 17mph". With enough reports like that, the company can find out the current traffic speed on that road.

And yes, it can be broken entertainingly - https://www.simonweckert.com/googlemapshacks.html

Thanks - I was wondering if the SatNav device was sending traffic data.

 

[Cross City]

Without wanting to Doxx myself. The company I work for, amongst other things, provides real time traffic updates for almost every built in car Sat Nav in the UK as well as to broadcast media. It works in a similar way to Google Maps traffic maps with the added input of human sourced traffic problems on top. It's very accurate and very fast.

There are teams of people who verify that the data theyre getting from satnavs regarding traffic flow is correct, as well as souring 1000s of local sources for traffic incidents as they happen, 99% of the time we're quicker than everybody to the news because we have actual people lookign for the incident.

Same goes for public transport. And travel news for trains, planes, ferries etc you hear on the TV, Radio, and from news outlets online will come from us.

I'm not sure if we supply data to Tom Tom or not but it's very likely.

 

[BanburyBlue]

Without wanting to Doxx myself. The company I work for, amongst other things, provides real time traffic updates for almost every built in car Sat Nav in the UK as well as to broadcast media. It works in a similar way to Google Maps traffic maps with the added input of human sourced traffic problems on top. It's very accurate and very fast.

There are teams of people who verify that the data theyre getting from satnavs regarding traffic flow is correct, as well as souring 1000s of local sources for traffic incidents as they happen, 99% of the time we're quicker than everybody to the news because we have actual people lookign for the incident.

Same goes for public transport. And travel news for trains, planes, ferries etc you hear on the TV, Radio, and from news outlets online will come from us.

I'm not sure if we supply data to Tom Tom or not but it's very likely.

So I'm guessing the busier the road the more accurate the traffic data is?

 

[Cross City]

So I'm guessing the busier the road the more accurate the traffic data is?

I would guess so but news on smaller roads often comes from local facebook groups or twitter pages, who are often very fast and accurate. There is some software that be use to confirm what they're saying is true but thats not my area of expertise at all, what what I do know though it's very accurate. Smaller roads tend to have the advantage of having easy street that run parallel so traffic build up is disipated more easily and jams don't hang around as long as they do on larger roads.

 

[stuu]

So I'm guessing the busier the road the more accurate the traffic data is?

Broadly yes. There is a limit below which traffic data isn't shown for minor roads - if you look at Google Maps traffic when there has been an incident closing a major road, it will often show busy traffic on the minor roads as drivers try to avoid an area. The amount of data they receive must be absolutely vast

Incidentally, what are the benefits of using a paid-for sat nav versus Google Maps?

 

[dgl]

There are essentially two systems for live traffic updates, newer units and ones with an internet connection of some sort will use that, connected to a server somewhere.
Older units and ones with no internet connection use a data feed sent via Classic FM (RDS-Traffic Message Channel), a service that is free in the UK. Classic FM is used in preference to the use of a BBC station as it's a commercial service and Classic FM was the only nationwide commercial FM radio station. The stick on antenna on some sat nav units will be a band II antenna for VHF/FM radio reception for the RDS-TMC signal.

 

[Ediswan]

There are essentially two systems for live traffic updates, newer units and ones with an internet connection of some sort will use that, connected to a server somewhere.
Older units and ones with no internet connection use a data feed sent via Classic FM (RDS-Traffic Message Channel), a service that is free in the UK. Classic FM is used in preference to the use of a BBC station as it's a commercial service and Classic FM was the only nationwide commercial FM radio station. The stick on antenna on some sat nav units will be a band II antenna for VHF/FM radio reception for the RDS-TMC signal.

Last time I checked, the UK is the one place where TMC is not free. UK maps with TMC codes include a licence fee. There is no further susbscription to pay.

 

[BanburyBlue]

Broadly yes. There is a limit below which traffic data isn't shown for minor roads - if you look at Google Maps traffic when there has been an incident closing a major road, it will often show busy traffic on the minor roads as drivers try to avoid an area. The amount of data they receive must be absolutely vast

Incidentally, what are the benefits of using a paid-for sat nav versus Google Maps?

In my case, the new SatNav came with free traffic updates for life, as part of the purchase price. I probably wouldn't have subscribed if it was a monthly/annual subscription.

How does Google Maps work? Do you have to have to have it set up on your smart phone/tablet, and visible as you drive?

 

[stuu]

How does Google Maps work? Do you have to have to have it set up on your smart phone/tablet, and visible as you drive?

Google Maps navigation works the same as any satnav I have ever used. You just set the route via the app on your phone, and it gives you audio and visual directions, but you don't need the screen on. For cars with Android Auto installed you just connect your phone via Bluetooth and it displays on the screen like any other system

 

[BanburyBlue]

Google Maps navigation works the same as any satnav I have ever used. You just set the route via the app on your phone, and it gives you audio and visual directions, but you don't need the screen on. For cars with Android Auto installed you just connect your phone via Bluetooth and it displays on the screen like any other system

I was told once that Google Maps is not as responsive as a traditional SatNav because updates need to traverse the mobile network. Is this true, or an urban myth?

 

[stuu]

I was told once that Google Maps is not as responsive as a traditional SatNav because updates need to traverse the mobile network. Is this true, or an urban myth?

An urban myth I would have thought, if there is any speed difference it's unlikely to be noticeable to the average user. Possibly one spread by sellers of sat navy!

 

[33109]

I used to have a tomtom go 50 but that got its feed from my phone.

I used to tether it via bluetooth & setup my phone as a hotspot so it got the feed via my data.

 

[JamesT]

I've got the slightly shinier Go 5000 model. It contains a sim card in order to get the live traffic updates. (Though map updates are still done by connecting to a PC to download a large file over USB). I assume TomTom have a very good bulk data deal with providers around Europe that they can absorb the cost of that into the price of their devices.