Navigation system for vehicles

Claim 2

The system according to claim 1, wherein said route searching means sets a high cost for the route, for which guidance is presently being given, stored in said route memory means and searches for a route having the lowest cost.

Claim 3

The system according to claim 1 or 2, wherein said route searching means has traffic information acquisition means for acquiring traffic information relating to each route, said route searching means setting a high cost for a route which is congested with traffic or under construction on the basis of the traffic information acquired by said traffic information acquisition means, and searching for a route having the lowest cost.

Claim 4

A navigation system for providing an automotive vehicle with route guidance automatically in accordance with a route set in advance, the system comprising: a present-position sensing unit for sensing the present position of the automotive vehicle; an information storage unit in which map information, route information, cost of data representing roads and branch points, and modification coefficients for modifying the cost corresponding to a plurality of search conditions have been stored; an input unit for entering a destination, a transit point and the search conditions and designating execution of a route search from the present position sensed by said present-position sensing unit to the destination or the transit point; notification means for outputting information for the purpose of route guidance; and a central processing unit having: route searching means for performing a route search from the present position to the destination or transit point in response to the designation of route search made by said input unit; route memory means for temporarily storing a route found by said route searching means; route-guidance control means for outputting, to said notification means, a signal for performing route guidance on the basis of the route stored; and route travel determination means for determining whether the present position of the automotive vehicle sensed by said present-position sensing unit is on the route stored in said route memory means; wherein said route searching means selects the modification coefficients in conformity with the search conditions, obtains the cost of data representing the roads and branch points and searches for a route having the lowest cost.

Claim 5

The system according to claim 4, wherein said route searching means sets a high cost for the route, for which guidance is presently being given, stored in said route memory means and searches for a route having the lowest cost.

Claim 6

The system according to claim 4 or 5 wherein said route searching means has traffic information acquisition means for acquiring traffic information relating to each route, said route searching means setting a high cost for a route which is congested with traffic or under construction on the basis of the traffic information acquired by said traffic information acquisition means, and searching for a route having the lowest cost.

Claim 7

A navigation system an automotive vehicle, comprising: en-route location setting means for setting a desired en-route location; a present-position sensing unit for sensing the present position of the automotive vehicle; route searching means for searching for a route to a destination via the set en-route location based upon map information stored beforehand in memory means and present-position information sensed by said present-position sensing means; and en-route location traversal determination means for determining whether the vehicle has passed through the en-route location by comparing position information indicative of the sensed present position of the vehicle and position information indicative of the en-route location; wherein said en-route location traversal determination means has first judging means for judging whether the sensed present position of the vehicle is on a suggested route from the en-route location to the destination, it being judged that the en-route location has been passed through if the present position of the vehicle is on the suggested route.

Claim 8

The system according to claim 7, wherein said en-route location traversal determination means has said first judging means and second judging means for judging whether the sensed present position of the vehicle has approached within a prescribed range distance of the en-route location, it being judged that the en-route location has been passed if either one of said first and second judging means renders an affirmative judgment.

Claim 9

The system according to claim 7 or 8, wherein said en-route location traversal determination means has guidance control means for performing guidance with regard to a suggested route from the en-route location to the destination in a case where judgment has been rendered to the effect that the en-route location has been passed.