Orlando (FL) - Most people have used GPS devices, but have you ever wondered where all the data comes from? At the CTIA Wireless convention in Orlando Florida, Tele Atlas company officials showed us their “Mobile Mapping Van” which collects data through several cameras, laser units and differential GPS unit. The data is then organized and sold to the big GPS makers like TomTom and Mapquest.
A first glance the van looks like something you would see at the DARPA Grand Challenge with a multitude of cameras, antennas and other gadgetry strewn along the top of the orange colored car. But unlike the robotically controlled cars of DARPA, this van requires a driver. The cameras record still images which contain lane information, traffic density and address numbers. Every few seconds all the cameras take a snapshot and send the data to an on-board server in the back of the van. Engineers told us that vans with more cameras are used in denser urban areas.
The van also has two laser range-finding units (LIDAR) from SICK. These provide a stream of data with height of overpasses, textures of walls and distance to objects.
A laptop is mounted in the front of the van and images are streamed to the screen through an Ethernet cable connected to the server. The driver has to monitor the quality of the images, making sure they aren’t too dark or overexposed.
Company engineers told us the van is just one way that Tele Atlas receives data. The company also uses thousands of other sources of data like public tax records and insurance data.