Abstract: A commuter route selection system (10) includes a portable device (12) for receiving a travel time for at least one preselected commuter route and disseminating the travel time to a user and a central facility (14) for storing the at least one preselected commuter route and for obtaining current traffic information for the preselected commuter route. The central facility (14) transmits a current travel time for the preselected commuter route to the portable device (12).

Abstract: Vehicle navigation apparatus (10) calculates an initial route to a destination (52) via connected road segments (55, 59) defined in a road map data base. In response to a can't do-reroute signal, indicative of the vehicle user determining unsuitability of following the initial route guidance instructions, a new route (55, 60, 61, 62, 59) to the destination is provided. Automatically excluded from the,new route is a maneuver (ordered road segment pair (55-59)) and/or a road segment of the initial route. This prevents the new route from including an initial guidance instruction which was determined as unsuitable. Also, calculated routes are provided by calculating the route from a predicated position of the vehicle at a subsequent time based on the vehicle's current position, direction and rate of travel. This ensures that when the route is provided at the subsequent time, the vehicle will not have passed the first maneuver to be implemented in the calculated route.

Abstract: A land vehicle navigation apparatus (10) has a vehicle navigation computer (11) which determines a navigation route and provides vehicle maneuver visual displays on a CRT display (13). The displays are preferably provided in the form of graphic arrow representations (26, 28) which are illustrated in perspective form with a tail of the arrow (26B, 28B) shown in the foreground and towards to the bottom of a display screen (20) and the head of the arrow (26A, 28A) shown in the background. A visual display of an effective bar graph, indicating the additional distance to be traveled prior to execution of the visually displayed vehicle maneuver, is visually provided and superimposed on the visually displayed vehicle maneuver graphic arrow. The bar graph comprises a series of stack horizontal bars (27, 29) superimposed on the arrow (26, 28) which is preferably shown in three dimensional form.

Abstract: A route planning system (10) uses a computer (11) and stored road data to calculate a desired route to a destination. Road data is stored in a multiple layer road map data memory (13) in hierarchical multiple layers (17, 18, 19), each layer defining roadways by stored road segments (1S1-3S7) which extend between nodes (135-365)that correspond to roadway intersections. A first or lower layer (17) of road data designates a large number of first layer vehicle roadways while a second or higher level layer (18 or 19) of road data designates only some of the large number of first layer roadways as second layer roadways. Preferably, stored second layer road segments (2S1-2S17 or 3S1-3S7) extend between intersections of the roadways designated in the second layer rather than between intersections of roadways in the second layer with roadways or road segments not designated in the second layer but designated in the first layer.