×

On-board vehicle navigation apparatus

  • US 5,774,071 A
  • Filed: 11/28/1995
  • Issued: 06/30/1998
  • Est. Priority Date: 11/30/1994
  • Status: Expired due to Term
First Claim
Patent Images

1. An on-board vehicle navigation apparatus, comprising:

  • a road network memory device which stores road network data;

    a destination assignment means which assigns a destination for a vehicle;

    a guide intersection assignment means which assigns guide intersections to be passed in reaching said destination by using said road network data;

    an oral instruction means for providing an oral instruction which orally indicates directions to turn when said vehicle nears a first next guide intersection of the assigned said guide intersections from a current position of said vehicle;

    a remaining distance determination means which determines whether or not the distance between a present position of the vehicle and said first next guide intersection is less than a first standard distance and a second standard distance which is shorter than the first standard distance;

    an intersection distance determination means which determines whether or not the distance between said first next guide intersection and a second next guide intersection immediately subsequent to said first next guide intersection among said guide intersections is less than a third standard distance; and

    an oral instruction addition means which, when the remaining distance determination means determines that the distance between the present vehicle position and said first next guide intersection is less than the second standard distance and when the intersection distance determination means determines that the distance between said first next guide intersection and said second next guide intersection is less than said third standard distance, adds a first additional oral instruction relating to said second next guide intersection to an original oral instruction which is given upon approaching said first next guide intersection;

    wherein said oral instruction addition means adds a second additional oral instruction instead of said first additional oral instruction when the distance between said first next guide intersection and said second next guide intersection is less than a fourth standard distance which is less than said third standard distance, and said second additional oral instruction indicating an urgency of a vehicle maneuver required at said second next guide intersection, which urgency is not indicated by said first additional oral instruction.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×