Toyota unveils map technology for navigation systems

RP news wires, Noria Corporation
Toyota Motor Corporation announced February 8 that it has developed the world's first* technology for automatically delivering differential map data to car navigation systems. This technology — which TMC has named "Map on Demand" — will be made available to drivers as a new feature of TMC's Japanese-market G-BOOK telematics service from the spring of 2007.

Map on Demand, which was jointly developed with Aisin AW Company Ltd., Zenrin Company Ltd., Denso Corporation and Toyota Mapmaster Incorporated, delivers updated data on all Japanese expressways and toll roads, as well as on roads near the registered home of the subscriber and on roads in the vicinity of user-specified destinations.  Data is delivered via cell phone networks, Internet downloads, etc.

Although conventional data updating and editing for car navigation maps is conducted on a nationwide basis — involving a large volume of data and requiring considerable data transfer time and cost — Map on Demand focuses only on updates for areas specified by users, in addition to data for expressways and toll roads. (See Figure 1.)

In cases in which a modified road extends beyond the area specified by users for updating, the update area is extended to include connection to another road. This allows the car navigation system to provide route-connection information, with such connection information covering all roads throughout Japan. (See Figure 2.)

And while conventional data renewal is done only twice a year — often resulting in a delay in the availability of up-to-date information — Map on Demand greatly shortens the renewal cycle by delivering data soon after roads have been changed. In the case of expressways and toll roads, updated data is sent out about seven days after a new thoroughfare is open to traffic; maps for other roads are updated as soon as relevant information becomes available.

* As of the end of January 2007, according to TMC survey


Figure 1: Differential map data delivery
Only the data showing that Road A has changed to Road B within the specified area is delivered.   Figure 1: Differential map data delivery


Figure 2: Mechanism for ensuring road connections
For new or altered Road C, which lies completely within the specified area, only the data on it is delivered.

For new or altered Road D, which continues outside the specified area, the update area is expanded and data including the connection to another road is delivered.  This ensures that the car navigation system provides route-connection.
  Figure 2: Mechanism for ensuring road connections


Technology of differential map data delivery technology
Technology of differential map data delivery technology