A hybrid navigation system [1] that performs route calculations and highly flexible natural speech location searches in the cloud using dynamic databases that combine probe data collected from the vehicle and external data, and transmits to on-board devices has been developed. The system automatically switches to the on-board device when the vehicle is out of mobile network communication range or when faster processing is required for tasks such as re-routing.
The transition between the on-board devices and the cloud provide a seamless user experience adapted to use conditions and other factors. In addition, representing the route downloaded from the cloud by the on-board device requires synchronizing the map with the cloud, and a map caching function has been used to reduce the volume of data that needs to be synchronized.
The cloud-based route calculation is based not only on average travel time, but on dispersion as well. Moreover, integrating entry and exit link direction data (straight line, left turn, or right turn) enables the system to present routes involving less driving time and more precise estimates of arrival time.
This paper describes the technological attributes of the above hybrid navigation system.