04984168 is referenced by 147 patents and cites 5 patents.

In a method for determining a route between a starting point and a destination which are located on a digitally memorized road map, the problem is to perform the necessary calculations for determining the route within a short time, even for extensive road systems. Otherwise, the results could arrive too late and could no longer lend the driver any aid in making a decision. The object is attained by dividing the road map into at least two levels of different grid density and regional size and storing it in memory. A plurality of smaller subregions of fine grid density are assigned to the lower level, and one or more larger subregions of coarser grid density are assigned to the higher level. Beginning with the lower level of the road map, a possible route is then studied; if the results are negative, a transition is made to the next-higher level, until a positive result is attained. Then the route is plotted within whatever level a positive result was attained in, for instance in the same level or back and forth between the levels.

Title
Method and apparatus for determining a route between a starting point and a destination
Application Number
7/307088
Publication Number
4984168
Application Date
August 24, 1989
Publication Date
January 8, 1991
Inventor
Dietmar Schlogl
Sibbesse
DE
Ernst Peter Neukrichner
Hildesheim
DE
Agent
Frishauf Holtz Goodman and Woodward
Assignee
Robert Bosch
DE
IPC
G06F 15/50
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