Vehicle navigation system which automatically adjusts to a changed travel route

Claim 1

A navigation system installed in a vehicle comprising: measurement means for measuring a current position of the vehicle and for outputting current position data; road map data storage means for storing road map data; display means for displaying information; display control means for permitting said display means to display the current position of the vehicle on the basis of the current position data and a road map around the current position of the vehicle on the basis of the road map data; transit point storage means for storing transit point data representing positions of a plurality of transit points located on a travel route from a start point to a destination and travel order data representing a travel order according to which the vehicle passes the transit points; guide means for representing guide information relating to the travel route on the basis of the transit point data and the travel order data; distance calculation means for continuously calculating a transit point distance from the current position, moving according to movement of the vehicle, to the transit point for each of the transit points on the basis of the current position data and the transit point data; comparison means for comparing the transit point distances with a predetermined reference distance during driving of the vehicle and for detecting a special transit point which transit point distance is smaller than the reference distance; and target point determination means for determining a target transit point to be passed next according to the travel order on the basis of the travel order data, wherein said target point determination means changes the target transit point to the transit point to be passed subsequently to the special transit point according to the travel order, when said comparison means detects the special transit point during driving of the vehicle.