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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.
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.