Vehicular navigation system

• US 20060009904A1
• Filed: 06/23/2005
• Published: 01/12/2006
• Est. Priority Date: 07/07/2004
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Sakashita, Naohiro, Ohmi, Masanori
• Granted Patent: US 7,499,801 B2
• Time in Patent Office: Days
• US Class Current: 701/200
• CPC Class Codes: G01C 21/3658 Lane guidance

Abstract

In a vehicular navigation system, it is determined that a branching point is present along a guidance route within a given distance from a guidance intersection. It is then determined that approaching the branching point by using a natural exit lane results in entering a road that is not included in the guidance route, wherein the natural exit lane is included in an exit road exiting from the guidance intersection and exits naturally from the guidance intersection along the guidance route. Before entering the guidance intersection, it is suggested that a lane change be required after passing through the guidance intersection. Thus, in a case that a lane change is needed just after passing through the guidance intersection, a driver can respond with a sufficient time period.

Claims

1. A vehicular navigation system comprising:

a branching point determining unit that determines that a branching point is present along a guidance route within a given distance from a guidance intersection;

a deviation determining unit that determines that approaching the branching point, which is determined to be present within the given distance, by using a natural exit lane results in entering a road that is not included in the guidance route, wherein the natural exit lane is included in an exit road exiting from the guidance intersection and exits naturally from the guidance intersection along the guidance route; and

a lane-change guiding unit that suggests before entering the guidance intersection that a lane change be required after passing through the guidance intersection, based on a result determined by the deviation determining unit.

2. The navigation system of claim 1, further comprising:

a lane-number determining unit for determining that an accessible entrance lane of an entrance road to the guidance intersection is only one, wherein the accessible entrance lane enters the guidance intersection and is accessible for turning right along the guidance route under a right-hand traffic regulation,

wherein, when the accessible entrance lane is determined to be only one by the lane-number determining unit and the natural exit lane is a rightmost lane of a plurality of exit lanes of the exit road, the deviation determining unit determines that approaching the branching point by using the natural exit lane results in entering a road that is not included in the guidance route.

3. The navigation system of claim 1, further comprising:

a lane-number determining unit for determining that an accessible entrance lane of an entrance road to the guidance intersection is only one, wherein the accessible entrance lane enters the guidance intersection and is accessible for turning left along the guidance route under a left-hand traffic regulation,

wherein, when the accessible entrance lane is determined to be only one by the lane-number determining unit and the natural exit lane is a leftmost lane of a plurality of exit lanes of the exit road, the deviation determining unit determines that approaching the branching point by using the natural exit lane results in entering a road that is not included in the guidance route.

4. The navigation system of claim 1,

wherein the lane-change guiding unit also suggests, before entering the guidance intersection, guidance relating to the guidance intersection in addition to that a lane change be required after passing through the guidance intersection.

5. A vehicular navigation system comprising:

a branching point determining unit that determines that a branching point is present along a guidance route within a given distance from a converging point;

a deviation determining unit that determines that approaching the branching point, which is determined to be present within the given distance, by using a natural exit lane results in entering a road that is not included in the guidance route, wherein the natural exit lane is included in an exit road exiting from the converging point and exits naturally from the converging point along the guidance route; and

a lane-change guiding unit that suggests before entering the converging point that a lane change be required after passing through the converging point, based on a result determined by the deviation determining unit.

6. A computer program product in a computer-readable medium for use in a vehicular navigation system, the product comprising:

instructions for determining that a branching point is present along a guidance route within a given distance from a guidance intersection;

instructions for determining that approaching the branching point by using a natural exit lane results in entering a road that is not included in the guidance route, wherein the natural exit lane is included in an exit road exiting from the guidance intersection and exits naturally from the guidance intersection along the guidance route; and

instructions for then suggesting, before entering the guidance intersection, that a lane change be required after passing through the converging point.

7. A computer program product in a computer-readable medium for use in a vehicular navigation system, the product comprising:

instructions for determining that a branching point is present along a guidance route within a given distance from a converging point;

instructions for determining that approaching the branching point by using a natural exit lane results in entering a road that is not included in the guidance route, wherein the natural exit lane is included in an exit road exiting from the converging point and exits naturally from the converging point along the guidance route; and

instructions for then suggesting, before entering the converging point, that a lane change be required after passing through the converging point.