| 摘要 |
PURPOSE: To make good use of a navigation system by predicting and displaying traffic congestion even when a driver travels in his or her familiar area. CONSTITUTION: A travel data processing part 20 measures the travel time from one intersection to the next intersection and stores a travel data storage part 21 with time zones of passage between adjacent intersections, the number (n) of passage, and the total travel time for the (n) times corresponding to the combination of the two adjacent intersections. A traffic congestion prediction part 22 finds a mean travel time from the total travel time between the adjacently located intersections and the passage frequency stored in the travel data storage part 21 and also finds the standard travel time between the adjacent intersections from map information. And, the mean travel time is compared with a standard travel time and when the mean travel time is shorter than the standard travel time, no traffic congestion between the adjacently located intersections is predicted, but when not, traffic congestion is predicted and stored in the travel data storage part 21, and a map drawing part 13 displays the traffic congestion states of respective roads distinctively on the basis of the traffic congestion information. |
