| 摘要 |
PROBLEM TO BE SOLVED: To provide a navigation device exactly predicting arrival time to a destination in the case of running a guided path. SOLUTION: The navigation device 1 comprises a date and time layer DB 172 for classifying roads into layers according to the characteristics of the road or date and time and storing the attributes classified based on the characteristics of the layers, running data indicating the distance and the necessary time for a vehicle to run according to the attributes, and a running information file 173 which stores average speed of every attribute calculated from the running data. The device classifies the road included in the guided path according to road class and classifies at every attribute based on the present date and time. Then the distance of the guided path at every classified attribute are calculated and by multiplying the average speed per hour of the corresponding attribute, the necessary time and arrival time to the destination are calculated. |
