| 摘要 |
PROBLEM TO BE SOLVED: To cause the state of existence of railroad crossings on roads to be appropriately reflected in a route calculation in the case of a navigation device equipped with a route search function. SOLUTION: In searching for a route from a present position to a destination, a control circuit divides roads on a map into a plurality of portions with intersections, etc., used as nodes. From road data with portions between nodes defined as links, the search for roads (links) and the calculation of their cost are successively performed to select a route minimizing the cost. Data expressing the existence of railroad crossings is added to the road data and railroad crossing data is previously stored that is made up of coefficient data set according to the opening/closing time of the railroad crossings classified by time zone. When a route is searched for, reference is made to data expressing the existence of railroad crossings annexed to the road data. If there is a crossing (S2; Y), access is made to the crossing data (S4), the time of passing the crossing is estimated (S5), coefficient data for a time zone within which the time of passing falls is extracted from the crossing data (S6), and the calculated costs of links are multiplied by the coefficient data (S7). |
