Patent ID: 6876921

Claim:
A car navigation system comprising: a storage unit for storing road data, wherein the road data is constituted by a plurality of nodes and a plurality of links, each of which interconnects between the nodes, and a plurality of road names, each of which corresponds to each of the links; a computation unit for computing a recommended route from a start point to an end point by using link costs that are assigned to the individual links, wherein the recommended route is constituted by recommended links among the plurality of links, so that a total of link costs possessed by the recommended links is a minimum among totals of link costs included in routes from the start point to the end point, wherein routing assistance from the start point to the end point is executed according to the recommended route, a re-computation command unit for commanding re-computation of the recommended route; and a cost change unit for increasing a link cost possessed by each link of a same-road-name group including at least two links, wherein the each link of the same-road-name group has a same road name, when the re-computation command unit commands the re-computation of the recommended route, wherein the computation unit executes re-computation of the recommended route by using the link costs increased by the cost change unit.