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How Satnav Maps Are Made
Barence writes "PC Pro has a feature revealing how the world's biggest satnav firms create their maps. Nokia's Navteq, for example, has a huge database of almost 24 million miles of road across the globe. For each mile of road there are multiple data points, and for each of those positions, more than 280 road attributes. The maps are generated from public data and driver feedback, not to mention its own fleet of cars with 360-degree cameras on the top. There's an IMU (inertial measurement unit) for monitoring the pitch of the road, and the very latest in 3D surface-scanning technology too. This light detection and ranging (LIDAR) detector captures 1.3 million three-dimensional data points every second, mapping the world around Navteq's field vehicles in true 3D. The feature also investigates whether commercial mapping firms will be replaced by open-source maps." That last line makes me think of the difference between conventionally published encyclopedias and Wikipedia; "replaced by" is an odd standard in a big marketplace of ideas.
...let me just warm up my 360 degree camera and my LIDAR gear, like we all have one, and go take mapping data for my neighbourhood...
Operation Guillotine is in effect.
Way back I worked at a DOT they were buying the sat maps from the Russians very good positional accuracy but no data to go with them. We would take the census maps that are useless for positions but have all the road names house numbers etc. The feds had sat maps as well but refused to sell them of give them to the states. We also merged it with data from a fleet of vans primarily with a gps and camera's (going to laser disk no less). A whole crew of people would spend all day matching things by hand and merging the data.
No sir I dont like it.
They have the WORST maps available. Most of it is wrong, very low detail in any town that is smaller than 300,000 people. And they charge anal rape prices for their map updates.
I had one of the first in car nav systems, the Clarion Auto PC and the navteq maps were borderline worthless. the maps were missing most roads, no data about most one way streets, etc..
In fact 10 years later in 2009 I had the unfortunate experience of using Navteq data in a Jeep Grand Cherokee Nav system and once again crap maps, and it even had roads in locations that have not existed for decades, so their data set is still out of whack so bad it's not funny.
No thanks. I avoid all products that say "Navteq map database" on them.
Garmin uses Navteq but then uses teleatlas to correct the mess that is Navteq. Their maps are a hybrid of 4 different map database sources ran through their servers to correct them. So far I have had OK luck with Garmin's source database. I stopped using Megallan as they switched to the Navteq low quality database.
Want good maps in your GPS? teleatlas as the data source.
Do not look at laser with remaining good eye.
Bingo, And that is why I'd like everybody to give Waze a serious try. Similar to OSM it's maps are editable. It requires an active data connection on your device to work fully and properly. As your driving it's continually reporting your location and speed data to their system. This allows it to dynamically route around traffic issues. This used to be the biggest selling point, but it's no longer that unique of a feature. What is unique is that every user is allowed to log into the map and make fixes.
How significant is this? Six months ago I discovered Waze, at the time I was using a TomTom device and was frustrated that finally two years after opening a major new commuter route had finally made it onto the TomTom maps. But another route that cut more time off my commute had just opened and I knew Tomtom wouldn't have it for years to come. When I fired up Waze, less than two months after the second commuter route had opened, it was already in their maps. The second benefit was I'd reported other errors via the TomTom reporting system without ever seeing the fixes getting made. I was able to go into the Maps in Waze and my fixes went active within a couple weeks.
Since then I've spent quite a bit of time cleaning up the roads in my area. I've mapped in a major road re-design and another new commuter route before they were open to traffic. I turned both on a couple weeks before the roads actually opened and both were live on the system the day each road opened. Contrast that to the first road and TomTom taking nearly two years to add it to their maps.
And best of all, Waze is free, those TomTom updates were $12 every quarter, for very slow updates. Waze is as accurate as the users in the area make it, it has helped me avoid several traffic jams and it's free! (as in beer). You don't have to edit or any thing, you just need an iOS or Android device (there are versions that will work on Winmobile, symbian and Blackberry devices but they are not updating those client apps at this time), with an active data connection and you are on your way.
I'm too lazy to compose a creative sig.
Natvteq has actually very good maps, particularly in Europe. The reason why your map looks bad is most likely due to your particular gear vendor. Garmin, Becker, Blaupunkt, Falk, etc. they buy maps from Navteq or Teleatlas, and they compile it for whatever their main goal and budget. In order to reduce the map size and save money, they compress the data using a battery of techniques. One common technique is decimation, where they simply remove geometry points to save space, leaving mostly the ones that represent intersections and a few in the middle. POI suffer as well.
So please don't be too fast in blaming a map vendor, where the fault is almost certainly from your navigation system vendor.