Navigation system performing route guidance for vehicle

• US 20050256638A1
• Filed: 04/19/2005
• Published: 11/17/2005
• Est. Priority Date: 05/14/2004
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Takahashi, Toshiaki, Inoue, Hirofumi
• Granted Patent: US 7,353,111 B2
• Time in Patent Office: Days
• US Class Current: 701/209
• CPC Class Codes: G01C 21/3461 Preferred or disfavoured areas, e.g. dangerous zones, toll or emission zones, intersections, manoeuvre types, segments such as motorways, toll roads, ferries
• CPC Class Codes: G01C 21/3484 Personalized, e.g. from learned user behaviour or user-defined profiles

Abstract

A preprocessing unit calculates a square sum SJ(t_n) of jerk J, and a driving characteristic calculation unit determines whether the jerk square sum SJ(t_n) is equal to or above a predetermined threshold value. The position/traveling direction determination unit determines the position and traveling direction of the vehicle. A troublesome driving place determination unit records an intersection at which the jerk square sum SJ(t_n) is calculated to be equal to or above the predetermined threshold value and the traveling direction of the vehicle at that time in association with each other in a troublesome driving place database. With reference to the troublesome driving place database, the troublesome driving place determination unit then calculates the risk cost at each intersection around the vehicle for each traveling direction. It is therefore possible to perform route guidance taking the driver'"'"'s personal feeling into an account.

Claims

1. A navigation system performing route guidance for a vehicle in which the navigation system is mounted, comprising:

a preprocessing unit calculating a second-order differential value of speed of the vehicle as a jerk and calculating an value obtained by accumulating any one of an absolute value and a square value of the jerk in a certain period of time;

a driving characteristic calculation unit determining whether the accumulated value is equal to or above a predetermined threshold value;

a position/traveling direction determination unit determining a position and a traveling direction of the vehicle;

a troublesome driving place database storing information of an intersection at which the accumulated value is calculated to be equal to or above the predetermined threshold value and information of the traveling direction of the vehicle at the intersection in association with each other; and

a troublesome driving place determination unit calculating a risk cost of a driver at each of intersections around the vehicle for each traveling direction of the vehicle with reference to the troublesome driving place database.

2. The navigation system according to claim 1, wherein

the troublesome driving place database includes a plurality of intersection shape patterns, determines an intersection shape pattern similar to a shape of the intersection at which the accumulated value is calculated to be equal to or above the predetermined threshold value from the plurality of intersection shape patterns, and stores information of the determined intersection shape pattern and the information of the traveling direction of the vehicle in association with each other.

3. The navigation system according to claim 1, further comprising:

a display map creation unit displaying map information around the vehicle on a display unit, wherein

the display map creation unit superimposes the risk cost calculated by the troublesome driving place determination unit at a position corresponding to the intersection on a map.

4. The navigation system according to claim 1, further comprising:

an interrupt message creation unit indicating information promoting safe driving in response to the traveling direction of the vehicle changing into a traveling direction with a higher risk cost at an intersection.

5. The navigation system according to claim 1, further comprising:

a route search computation unit searching for a route to a destination set, wherein

the route search computation unit searches for a route to the destination under the condition that the risk cost is minimized with reference to the troublesome driving place database.

6. The navigation system according to claim 1, further comprising:

a neighborhood search computation unit retrieving facilities around the vehicle, wherein

the neighborhood search computation unit retrieves the facilities around the vehicle under the condition that the risk cost to each facility is minimized with reference to the troublesome driving place database.

7. A navigation system performing route guidance for a vehicle in which the navigation system is mounted, comprising:

a preprocessing unit calculating a second-order differential value of speed of the vehicle as a jerk and calculating a value obtained by accumulating any one of an absolute value and a square value of the jerk in a certain period of time;

a driving characteristic calculation unit determining whether the accumulated value is equal to or above a predetermined threshold value;

a traveling situation determination unit determining a traveling situation of the vehicle;

an environmental change factor determination unit determining an environmental change factor outside the vehicle;

an environmental change risk database storing information of the traveling situation of the vehicle and information of the environmental change factor when the accumulated value is equal to or above the predetermined threshold value in association with each other; and

an environmental change risk determination unit calculating a risk cost of a driver to the environmental change factor outside the vehicle for each traveling situation.

8. The navigation system according to claim 7, further comprising:

a display map creation unit displaying map information around the vehicle on a display unit, wherein

the display map creation unit superimposes and displays the traveling situation with a high risk cost for the driver in the current environmental change factor on the map information.

9. The navigation system according to claim 7, further comprising:

an interrupt message creation unit indicating information promoting safe driving in response to the traveling situation of the vehicle changing into the traveling situation with a higher risk cost for the driver.

10. The navigation system according to claim 7, further comprising:

a route search computation unit searching for a route to a set destination, wherein

the route search computation unit searches for a route to the destination under the condition that the risk cost is minimized with reference to the environmental change risk database.

11. The navigation system according to claim 7, further comprising:

a neighborhood search computation unit retrieving facilities around the vehicle, wherein

the neighborhood search computation unit retrieves the facilities around the vehicle under the condition that the risk cost to each facility is minimized with reference to the environmental change risk database.