WO2009014326A1

WO2009014326A1 - Navigation system and method for guiding map correcting

Info

Publication number: WO2009014326A1
Application number: PCT/KR2008/003770
Authority: WO
Inventors: Hak Soo Kim
Original assignee: Thinkware Systems Corporation
Priority date: 2007-07-23
Filing date: 2008-06-28
Publication date: 2009-01-29
Also published as: KR100944642B1; KR20090010378A

Abstract

A navigation system and map correction guidance method is provided. The map correction guidance method in a navigation system, the method including: retrieving a route to a destination set by a user, and providing guidance about the retrieved route; and determining a predetermined map correction point on the retrieved route and automatically providing guidance about map correction with respect to a current location of the user.

Description

NAVIGATION SYSTEM AND METHOD FOR GUIDING MAP CORRECTING

Technical Field

The present invention relates to a navigation system, and more particularly, to a navigation system and map correction guidance method to overcome a location error of a Global Positioning System (GPS) using map-matching correction.

Background Art

A navigation system is a system which provides information for driving of a transportation device, such as a vehicle, using an artificial satellite. The navigation system is automatic.

The navigation system receives predetermined data from a Global Positioning System (GPS) satellite above the Earth using a GPS receiver, and calculates its own location based on the received data. A route guidance service map-matches the calculated location with previously stored map data, and retrieves a route to a destination set by a user from a current location of a moving object. Accordingly, a route guidance service may provide guidance about the route.

A location of a moving object may be inaccurately calculated. That is, the location outputted from a GPS module may have an error of about several tens of meters. Accordingly, when the calculated location is outside of a route based on map data, the moving object may be corrected to be on a road which is located closest to the moving object using a map-matching method.

As described above, a general navigation system obtains location information of a moving object using a GPS signal, and a location error of a GPS module is overcome using a map-matching method.

However, when a GPS status is not good, for example, in tunnel or around high- rise buildings, map-matching may be incorrectly performed. Also, a matching error may occur in an environment such as roads located closely and parallel to each other, an overpass and underpass, an underground pass, and the like. The matching error is generated due to a characteristic of a GPS signal, and may prevent a correct route from being provided to a user. A navigation system in a conventional art provides a map correction function to enable a user to perform map-matching correction on his/her own. When a user recognizes that a road matched with respect to a current location of the user is incorrect through a screen of the navigation system, the navigation system may execute the map correction function to perform map-matching correction.

However, in the navigation system in a conventional art, when map-matching is performed in roads located closely and parallel to each other, a user may not recognize a map-matching error through a map screen of the navigation system. Also, the user may not determine when to perform map-matching correction. In the navigation system in a conventional art, determining a map-matching error and when to perform map correction are mainly based on a user's determination. Also, when a user is does not know how to operate a map correction function, the user may not use the map correction function.

Disclosure of Invention

Technical Goals

The present invention provides a navigation system and map correction guidance method which automatically provides a map correction function to lead to accurate map-matching with respect to a road where a user is driving. The present invention also provides a navigation system and map correction guidance method which enables a user to use a map correction function more easily.

Technical solutions

According to an aspect of the present invention, there is provided a map correction guidance method in a navigation system, the method including: retrieving a route to a destination set by a user, and providing guidance about the retrieved route; and determining a predetermined map correction point on the retrieved route and automatically providing guidance about map correction with respect to a current location of the user. According to another aspect of the present invention, there is provided a navigation system, including: a user interface providing a map correction menu to enable a user to correct map-matching with respect to a current location; and a control unit retrieving a route to a destination set by the user, providing guidance about the route, and when a predetermined map correction point is sensed while driving along the retrieved route, automatically executing the map correction menu.

Advantageous Effects

According to an embodiment of the present invention, a navigation system and map correction guidance method automatically recognizes a time for map-matching correction, and thereby may provide an improved map correction function.

Also, according to an embodiment of the present invention, a navigation system and map correction guidance method automatically outputs a user menu for map correction when a time for map-matching correction is sensed, to provide a map correction guidance, and thereby may enable a user to recognize a map-matching error more easily, enable the user to access a map correction menu more conveniently, and guarantee smooth map correction based on an accurate timing for map correction.

Brief Description of Drawings

FIG. 1 is a block diagram illustrating a configuration of a navigation system according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating an example of a branch road, located parallel to a main road, in a road type where a map-matching error may easily occur;

FIG. 3 is a diagram illustrating an example of an adjacent road, located closely and parallel to a main road, in a road type where a map-matching error may easily occur;

FIG. 4 is a flowchart illustrating a map correction guidance method in a navigation system according to an embodiment of the present invention; and

FIG. 5 is a diagram illustrating an example of a user interface menu with respect to a map correction function according to an embodiment of the present invention.

Best Mode for Carrying Out the Invention Hereinafter, embodiments of the present invention are described in detail by referring to the figures.

FIG. 1 is a block diagram illustrating a configuration of a navigation system according to an embodiment of the present invention.

According to an embodiment of the present invention, the navigation system includes a Global Positioning System (GPS) module 110. The GPS module 110 receives a location signal from at least three GPS satellites, and calculates its own location.

The navigation system is a user terminal which provides guidance about a retrieved route to a destination set by a user. In particular, the navigation system may recognize a time for map-matching correction while driving along the retrieved route, and automatically execute a user interface (UI) to enable the user to perform map correction more easily.

According to an embodiment of the present invention, the navigation system includes a route retrieval unit 120, storage unit 130, UI 140, display unit 150, voice output unit 160, and control unit 170.

The storage unit 130 includes a map database including map data of a national map and route guidance data associated with the map data. Also, the storage unit 130 stores a route guidance control program to control an entire operation of the navigation system including a route guidance function. The route guidance control program includes a UI control program and map correction determination program. The UI control program controls a UI for route retrieval and route setting. The map correction determination program determines a current location of the user or a time for map- matching correction.

The route retrieval unit 120 ascertains a current location of the user using a

GPS signal received from the GPS module 110. Also, the route retrieval unit 120 retrieves a route, hereinafter, referred to as a retrieved route, to the destination set by the user from the current location in the map data stored in a map database of the storage unit 130, and generates route information.

The control unit 170 map-matches the current location of the user with map data corresponding to the retrieved route under the route guidance control program. Also, the control unit 170 determines driving status and whether the user is outside of the retrieved route based on the current location, and provides route guidance information based on the determination. Specifically, the control unit 170 recognizes a point in time for map-matching correction, hereinafter, referred to as a map correction point, with respect to the current location or retrieved route, while providing guidance about the retrieved route under the map correction determination program. Also, when the map correction point is sensed, the control unit 170 automatically executes a map correction menu to enable the user to change a map-matched road under the UI control program.

The control unit 170 determines the map correction point based on the map data stored in the map database. Specifically, the control unit 170 determines a point where a map-matching error may occur or map-matching correction is required in software.

Also, the display unit 150 displays map information for the route guidance and a variety of contents according to each system operation. A Liquid Crystal Display (LCD) or Electro Luminescence (EL) display may be used as the display unit 150.

The UI 140 is for inputting a user command with respect to a route guidance function, for example, inputting a destination, and user command with respect to the map correction function, for example, selecting a matching road. The UI 140 may be a touch pad formed integrally with the display unit 150, and provides a graphical user interface unit. Every menu environment associated with the route guidance function and map correction function of the navigation system may be provided as a graphic screen through the display unit 150. A user command may be inputted by touching a particular location on the graphic screen using a stylus pen, fingers, and the like. The voice output unit 160 provides voice guidance about the retrieved route.

The map correction point is described in greater detail below.

FIG. 2 is a diagram illustrating an example of a branch road, located parallel to a main road, in a road type where a map-matching error may easily occur. FIG. 3 is a diagram illustrating an example of an adjacent road, located closely and parallel to a main road, in a road type where a map-matching error may easily occur.

As illustrated in FIG. 2, when a user enters a road on a right side in an intersection while driving a main road, a road matched with respect to a location of the user on a map, that is, matching road, may be still indicated as the main road after a route is changed. When the main road is located parallel to the right-side road, and a branching angle between the main road and right road is less than a predetermined set angle, the location of the user may be matched with the main road even when the user drives on the right road. Accordingly, an incorrect route may be provided.

A control unit 170 senses a cross point where a branching angle between off- ramps is less than a predetermined set angle, and determines the cross point as a map correction point to overcome a map-matching error. The cross point branches off into a plurality of off-ramps.

That is, the map correction point may be a point where the main road branches off to another road located parallel to the main road. The map correction point may include a cross point where a road to enter an overpass and a road that branches off from the road exist, a point where a branch road branches off from a main road located parallel to the branch road, a point where an off-ramp branches off from an express way, and the like.

Also, as illustrated in FIG. 3, when a GPS signal fails to be generated" while the user drives along any one road, that is, a driving road, of two roads located parallel to each other, a route to a destination may be re-retrieved. Also, map-matching with respect to a current location of the user or retrieved route may be changed to another road, that is, a matching road. In this instance, the matching road is close to the driving road. That is, even though the user drives along the retrieved route, a route may be re-retrieved and map-matching road may be changed due to the failure of the generation of the GPS signal. Accordingly, an incorrect route may be provided. The control unit 170 senses a route re-retrieval point and map-matching change point, and determines the route re-retrieval point and map-matching change point as a map correction point to overcome a map-matching error. The route re-retrieval point is a point where a route is re-retrieved. The map-matching change point is a point where map-matching is changed from a road being driven on to another road. According to an embodiment of the present invention, while providing guidance about the retrieved route, a cross point where a map-matching error may occur, a route re-retrieval point, or a map-matching change point may be determined. Also, when the map correction point such as the cross point, route re-retrieval point, and map- matching change point are sensed, guidance for map correction may be automatically provided to the user.

A control method of the control unit 170 for the automatic guidance for map correction is described in greater detail with reference to FIG. 4. As illustrated, in operation S410, when a user sets a destination using a route guidance function, a route to the set destination is retrieved based on a current location of the user.

In operation S420, a map corresponding to the retrieved route is provided, and map-matching with respect to the current location is performed on the map. A map screen and voice guidance about the retrieved route are provided to enable the user to drive along the retrieved route.

In operation S430, while driving along the retrieved route, it is determined whether a map correction point that is determined as a cross point, route re-retrieval point, or map-matching change point is sensed.

In operation S440, when the map correction point is sensed, a UI corresponding to a map correction function is automatically executed. That is, when the map correction point is sensed, a pop-up of a map correction menu is executed.

The map correction menu includes a road list including roads where map- matching with respect to the current location may be changed. A road corresponding to the retrieved route and a road located close to the road are retrieved based on a current location of the user when the map correction point is sensed. Accordingly, the road list including the retrieved roads is provided on the map correction menu.

FIG. 5 is a diagram illustrating an example of a map correction menu 510 according to an embodiment of the present invention.

As illustrated in FIG. 5, the map correction menu 510 is displayed on a map when the map correction point is sensed.

The map correction menu 510 provides a time for map correction or a time when map correction is available, and a predetermined guidance message. The guidance message indicates the user of map correction, for example, "Map-matching correction is available. Select a road". Also, the map correction menu 510 includes the road list.

The road list may include a main road corresponding to the retrieved route and at least one adjacent road. The at least one adjacent road is close to the main road and located parallel to the main road in a same driving direction. Also, the road list may include a main road corresponding to the retrieved route and at least one branch road.

The at least one branch road branches off from the main road within a branching angle less than a predetermined set angle.

For example, when a cross point illustrated in FIG. 5 is determined as the map correction point, the road list is provided to enable the user to select any one of the main road ((D direction) and branch road (φ direction) for map-matching with respect to the current location. The branch road branches off from the main road.

When the user selects a road where the user is located or a road where the user desires to match from the road list through the map correction menu 510 in operation S450, map-matching with respect to the current location of the user is changed to the selected road and map correction is performed in operation S460. Accordingly, a UI that automatically recognizes a point for map correction and performs map correction when the point is sensed is automatically provided.

The above-described embodiment of the present invention may be recorded in computer-readable media including program instructions to implement various operations embodied by a computer. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. The media and program instructions may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD ROM disks and DVD; magneto-optical media such as floptical disks; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher level code that may be executed by the computer using an interpreter. The described hardware devices may be configured to act as one or more software modules in order to perform the operations of the above-described embodiments of the present invention.

Although a few embodiments of the present invention have been shown and described, the present invention is not limited to the described embodiments. Instead, it would be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A map correction guidance method in a navigation system, the method comprising: retrieving a route to a destination set by a user, and providing guidance about the retrieved route; and determining a predetermined map correction point on the retrieved route and automatically providing guidance about map correction with respect to a current location of the user.

2. The map correction guidance method of claim 1, wherein the automatically providing guidance about the map correction comprises: determining the map correction point while driving along the retrieved route; and automatically executing a user interface providing the user with the map correction guidance when the map correction point is sensed.

3. The map correction guidance method of claim 2, wherein the determining comprises: sensing a cross point that branches off into a plurality of off-ramps while driving along the retrieved route; and determining, when the cross point is sensed, the sensed cross point as the map correction point.

4. The map correction guidance method of claim 2, wherein the determining comprises: sensing a cross point where a branching angle between the off-ramps is less than a predetermined set angle, the cross point branching off into a plurality of off- ramps while driving along the retrieved route; and determining, when the cross point is sensed, the sensed cross point as the map correction point.

5. The map correction guidance method of claim 4, wherein the cross point where the branching angle between the off-ramps is less than the predetermined set angle includes an off-ramp, extended from a main road, and an off-ramp corresponding to at least one branch road that branches off from the main road within the predetermined set angle.

6. The map correction guidance method of claim 2, wherein the determining comprises: sensing a route re-retrieval point where a route to the destination is re-retrieved while driving along the retrieved route; and determining the sensed route re-retrieval point as the map correction point.

7. The map correction guidance method of claim 2, wherein the determining comprises: sensing a map-matching change point where map-matching with respect to the current location of the user is changed to another road while driving along the retrieved route; and determining the sensed map-matching change point as the map correction point.

8. The map correction guidance method of claim 2, wherein the automatically executing the user interface comprises: retrieving a road corresponding to the retrieved route and a road around the retrieved route based on the current location of the user when the map correction point is sensed; and executing a map correction menu including a road list including the retrieved road.

9. The map correction guidance method of claim 8, wherein the automatically executing the user interface comprises: selecting, by the user, any one road from the road list through the executed map correction menu; and changing map-matching with respect to the current location of the user to the selected road.

10. The map correction guidance method of claim 9, wherein the road list includes a main road corresponding to the retrieved route and at least one adjacent road which is apart from the main road by a predetermined distance and located parallel to the main road in a same driving direction.

11. The map correction guidance method of claim 9, wherein the road list includes a main road corresponding to the retrieved route and at least one branch road that branches off from the main road within a branching angle less than a predetermined set angle.

12. A computer-readable recording medium storing a program for implementing the method according to any one of claims 1 through 11.

13. A navigation system, comprising: a user interface providing a map correction menu to enable a user to correct map-matching with respect to a current location; and a control unit retrieving a route to a destination set by the user, providing guidance about the route, and, when a predetermined map correction point is sensed while driving along the retrieved route, automatically executing the map correction menu.

14. The navigation system of claim 13, wherein, when a cross point, route re- retrieval point, or map-matching change point is sensed, the control unit determines the sensed cross point, route re-retrieval point, or map-matching change point as the map correction point, the cross point branching off into a plurality of off-ramps and being a point where a branching angle between the off-ramps is less than a predetermined set angle, the route re-retrieval point being a point where a route to the destination is re- retrieved, and the map-matching change point being a point where map-matching with respect to the current location of the user is changed to another road.

15. The navigation system of claim 13, wherein the control unit provides a road list through the map correction menu when the map correction point is sensed, and changes map-matching with respect to the current location of the user to a selected road when the user selects a road from the road list through the map correction menu, the road list including a main road corresponding to the retrieved route, and at least one branch road that branches off from the main road or at least one adjacent road close to the main road.