Navigation system with recalculation of return to guidance route

• US 5,652,706 A
• Filed: 06/26/1995
• Issued: 07/29/1997
• Est. Priority Date: 08/19/1992
• Status: Expired due to Term

• Current Assignee: Aisin AW Company Limited (Aisin Corp.)
• Original Assignee: Aisin AW Company Limited (Aisin Corp.)
• Inventors: Ohara, Shigekazu, Nimura, Mitsuhiro, Masuda, Hiroyoshi, Maekawa, Kazuteru, Morimoto, Kyoumi
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US08/494,891
• Time in Patent Office: 764 Days
• Field of Search: 364/449, 364/443, 364/444, 364/450, 364/424.01, 364/424.02, 364/447, 364/424.03, 340/990, 340/995, 340/988, 340/460, 340/996, 340/692
• US Class Current: 701/210
• CPC Class Codes: G01C 21/3415 Dynamic re-routing, e.g. recalculating the route when the user deviates from calculated route or after detecting real-time traffic data or accidents
• CPC Class Codes: G05D 1/0259 using magnetic or electromagnetic means
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30
• CPC Class Codes: G05D 1/0278 using satellite positioning signals, e.g. GPS

Abstract

Geographical, guide or search information and route information are stored in storage sections. An arithmetic section provides a route researching function with preference for the traveling direction of a vehicle. A route-calculating section is provided for re-calculating the route, and a route guide control system is also provided, inclusive of a route deviation-detecting section. The re-calculating section calculates either the shortest route from the point of deviation to the previous route or a new route to the destination. In case of the search of the shortest route to the previous route, the shortest route from the present location to the previous route is searched giving preference to the traveling direction, e.g. avoidance of a U-turn, on the basis of the search information relating to the immediate vicinity of the present location, so that the route to rejoin the previous route can be quickly calculated. In case of search of a new route, the whole route from the present location to the destination is searched, again giving weight to the present traveling direction, on the basis of the search information relating to the area between the present location and the destination, to guide the driver along a new route completely different from the previous one.

Claims

1. A vehicular navigation system for automatically guiding a driver of a vehicle to a destination, comprising:

present-position determining means for determining the present location and present direction of travel of the vehicle;

geographical information storage means for storing geographical data inclusive of navigation information and guide information, which navigation and guide information can be used to calculate routes and to guide a driver along calculated routes;

destination input means for inputting a destination;

initial route calculating means for retrieving geographical data from the geographical information storage means and for using the retrieved first geographical data to calculate a guidance route from the present location to the destination;

route storage means for storing data of the guidance route;

route guide control means for retrieving guidance route data from the route storage means and for using the retrieved guidance route data to guide a driver to the destination;

detecting means for detecting a deviation of the vehicle from the guidance route;

re-calculation command input means responsive to the detecting means detecting a deviation for commanding a route re-calculation;

re-calculating means responsive to a route re-calculation command from the re-calculation command input means for retrieving from the geographical information storage means a subset of said geographical data related to a vicinity of the detected present location, for retrieving guidance route data from the route storage means, for searching said subset of geographical data to select an optimum rejoinder point on the guidance route within said vicinity of the detected present position, for using the retrieved subset of geographical data to calculate a correcting route from the detected present location to the selected rejoinder point on the guidance route in accordance with the detected present direction of travel, for combining route data for the selected correcting route with a portion of the guidance route data retrieved from the route storage means to form a new guidance route consisting of the correcting route and a section of said guidance route extending from said rejoinder point to said destination, and for replacing the stored data in the route storage means with the combined data forming the new guidance route; and

whereby

said route guide control means after re-calculation by said re-calculation means guides the driver in accordance with the combined data forming the new guidance route.

2. The vehicular navigation system of claim 1 wherein said recalculating means calculates the correcting route by determination of the shortest route between the detected present position and the guidance route and setting said shortest route as the correcting route.

3. The vehicular navigation system of claim 1 wherein said re-calculating means calculates the correcting route by linking together prioritized intersections located in the vicinity of the detected present position, said prioritized intersections being those intersections located by said re-calculating means in the vicinity of the detected present position having the lowest total penalty values, said re-calculating means assessing intersections located in the vicinity of the present position penalty values on the basis of distance between the detected present position and the guidance route and traffic signals.

4. The vehicular navigation system of claim 1 wherein said recalculating means selects as said rejoinder point a point on the guidance route ahead of the detected present location.

5. A vehicular navigation system for automatically guiding a driver of a vehicle to a selected destination, comprising:

geographical information storage means for storing geographical data inclusive of navigation information and guide information which navigation and guide information can be used to calculate routes and to guide a driver along calculated routes;

present position determining means for determining the present location and present direction of travel of the vehicle;

destination input means for inputting a destination;

initial route calculating means for retrieving first geographical data from the geographical information storage means and for using the retrieved first geographical data to calculate a guidance route from the present location to the destination;

route storage means for storing data of the guidance route;

route guide control means for retrieving guidance route data from the route storage means and for using the retrieved guidance route data to guide a driver to the destination;

detecting means for detecting a deviation of the vehicle from the guidance route;

re-calculating means, responsive to the detecting means detecting a deviation, for retrieving second geographical data from the geographical information storage means, for retrieving guidance data from the route storage means, for using the retrieved second geographical data to calculate a correcting route from the detected present location to a rejoinder point on the guidance route, for combining route data of the correcting route with a portion of the guidance route data retrieved from the guidance storage means to form a first new route consisting of the correcting route and a section of said guidance route extending from said rejoinder point to said destination, and for using the retrieved second geographical data to calculate a second new route from the detected present location to the selected destination; and

means for selecting said first new route or said second new route according to an input condition or a set condition to replace the guidance route data in said route storage means with data of the selected first or second new route, and whereby the route guide control means guides the driver according to the selected new route.

6. The vehicular navigation system of claim 5 wherein said re-calculating means calculates the correcting route by determination of the shortest route between the detected present position and the guidance route and setting said shortest route as the correcting route.

7. The vehicular navigation system of claim 5 wherein said re-calculating means calculates the correcting route by linking together prioritized intersections located in the vicinity of the detected present position, said prioritized intersections being those intersections located by said re-calculating means in the vicinity of the detected present position having the lowest total penalty values, said re-calculating means assessing intersection located in the vicinity of the present position penalty values on the basis of distance between the detected present position and the guidance route and traffic signals.