05262775 is referenced by 67 patents and cites 6 patents.

Where a vehicle deviates from a calculated optimal route, the system displays a message indicating the vehicle's deviation. The driver of the vehicle commands computation of a new optimum route. The system selects a new starting point from a point substantially ahead of the vehicle, recomputes the optimal route, and determines the route from the new starting point to the destination. The new starting point is far enough ahead of the vehicle to ensure that the route computation is completed before the vehicle reaches it. This prevents overrunning the new starting point before the calculation of a new optimum route is completed. Navigation guidance, computed for the new optimal route, is then displayed.

Title
Navigation system with off-route detection and route recalculation
Application Number
7/864515
Publication Number
5262775
Application Date
April 7, 1992
Publication Date
November 16, 1993
Inventor
Tatsuhiko Abe
Saitama
JP
Haruhisa Tamai
Sunnyvale
CA, US
Agent
Thomas R Morrison
Assignee
Zexel Corporation
JP
IPC
G08G 1/123
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