The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 01, 1994
Filed:
Apr. 14, 1992
Haruhisa Tamai, Sunnyvale, CA (US);
Tatsuhiko Abe, Saitama, JP;
Zexel Corporation Daihatsu-Nissan Ikebukuro, Tokyo, JP;
Abstract
A navigation system prevents a vehicle from deviating from a new optimal route immediately after the new optimal route has been computed following the first deviation of the vehicle from an original optimal route. The system does this by determining the present location of the vehicle and searching road network data in a map database for a plurality of locations that are farther away from the present location than a distance travelled by the vehicle during recomputation of a new optimal route. These locations are selected as candidate new starting points. Then the system recomputes an optimal route from each of the candidate starting points to the destination. After the recomputation, the present location of the vehicle is read into the system, and an optimal route from the present location to each candidate starting point is computed. From the plurality of optimal routes from the present location of the vehicle to the destination via respective candidate starting points, the route that satisfies such conditions as, for example, to reach the destination by the shortest distance, in the shortest time, is selected as the new optimal route.