JP2004286524A - Method for changing map information and navigation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform seamless path guidance using up-to-date map information at lost costs. <P>SOLUTION: The map information is constituted of a plurality of levels. A level 0 is made the exclusive level of unguided object roads which are not used for path search, and a level 1 is made the level of guided object roads except for the unguided object roads. When the map information is changed, only the map information not less than the level 1 is changed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a map information changing method and a navigation device, and in particular, sets level 0 (LV0) to a dedicated level for narrow streets (non-guided roads), separates narrow streets and guided roads to form map information, The present invention relates to a map information change method and a navigation device that change map information by updating only a guide target road when changing information.
[0002]
[Prior art]
Recent map data has a hierarchical structure in which at least two layers of road information, a lower layer and an upper layer, are provided for each figure, and a route search is performed using map data having such a structure. Here, the figure leaf is a rectangular map portion obtained by dividing a map of a predetermined scale by a predetermined longitude width and a predetermined latitude width.
FIG. 10 is a schematic explanatory diagram of a route search process using map data having a hierarchical structure, and shows an example of map data having three layers. As shown in the figure, in the map data having a hierarchical structure, a map divided into smaller areas is set in a lower hierarchy, and map data is created for each map. The map data corresponding to each figure in the lower hierarchy (level 1) includes road information of all guidance target roads including expressways, toll roads, national roads, general roads, and prefectural roads. Further, as the upper hierarchy (level 1 and level 2), the map is divided into larger areas, and map data including roads of the corresponding level or higher is created for each map. The map data corresponding to each figure at the highest level (level 2) includes only road information mainly for major roads such as expressways, toll roads, and national roads. In addition to levels 1 to 3, there is a level 0 which includes all road information including a narrow street (non-guide target road) which is not a route guidance target, and a map drawing is performed using the level 0 map data. Is
[0003]
In the route search from the departure point SP on the level 1 road to the destination DP on the level 1 road, first, the departure is performed using the map data of the lowest layer (level 1) including more detailed road information. The route from the destination SP and the destination DP to a national road or the like which is also commonly included in the map data of the middle class (level 2) is searched. Next, using the map data of the intermediate layer, a route from the departure point side and the destination side to the road which is also commonly included in the map data of the uppermost layer (level 3) is searched. Thereafter, using the map data of the uppermost layer, a route search is performed from the starting point side SP 'to the destination point DP' of the uppermost layer with the main road as a search target. When the departure place SP and the destination DP exist on the narrow street, the departure place on the narrow street is used near the departure place SP and the destination DP using the level 0 map information. And a narrow street search from a point on the level 1 road to a destination on the narrow street.
When the route search is completed, the searched route information is converted into the level 0 map information, and the searched route is drawn using the converted level 0 route information.
[0004]
FIG. 11 is a map information explanatory diagram of levels 0 to 3, where level 0 includes road information of all non-guided roads (narrow streets) and guided roads, and level 1 indicates all guidance other than non-guided roads. Level 2 includes roads having a width equal to or greater than the first set length, and level 3 includes roads, expressways, and toll roads having a width equal to or greater than the second set length.
FIG. 12 is an explanatory diagram of a function using the current level 0 data. Using this level 0 data, map drawing, route drawing, narrow street search, route guidance (intersection enlarged view display), and map matching processing are performed. . The map drawing, route drawing, and narrow street search functions have already been described. The intersection enlarged view display is a function of creating and displaying an intersection enlarged view using level 0 map information when approaching an intersection. The map matching is a function of performing a map matching process using level 0 map information.
[0005]
Recent navigation devices read map information at a high speed by recording the map information on a hard disk (HDD), display a search route, display a desired map, and perform various navigation controls at a high speed. . In the case of such an HDD navigation device, if the map information recorded on the HDD becomes obsolete, it can be dealt with by rewriting with new map information.
In a navigation device using a rewritable recording medium such as an HDD, there are the following two methods for rewriting to a new version of map information.
The first method is to prepare several DVD-ROMs of the latest data and copy them to the HDD, and the second method is to use only the map information of the area that has been changed by communication or using a memory card or the like. Is partially updated using difference data (Patent Document 1).
[Patent Document 1] JP-A-11-95657 (Summary and FIG. 1)
[0006]
[Problems to be solved by the invention]
In the first method, the latest disc must be purchased. Therefore, the cost for the user is not different from that of the conventional DVD navigation device. Further, since data of 8 GB or more must be copied to the HDD, there is a problem that it takes time.
In the second method of performing partial update using difference data in Patent Document 1, it is difficult to perform seamless route guidance between an updated area and an unupdated area. In order to perform seamless route guidance, it is necessary to manually rewrite connection information between figures and levels (it is difficult to automate), and the cost is increased due to the labor involved.
In view of the above, it is an object of the present invention to enable seamless route guidance using the latest map information at a low cost without purchasing the latest disc.
[0007]
[Means for Solving the Problems]
In the map information changing method of the present invention, the map information is composed of a plurality of levels, level 0 is a dedicated level for non-guided roads not used for route search, and level 1 is a level of guide-target roads other than non-guided roads. When changing the map information, only the map information of level 1 or higher is changed.
Approximately 90% of the road data updated by the version upgrade of the map information is a non-guided road (narrow street). The non-guided road is data that is rarely used for route guidance. If route guidance can be performed using map information of level 1 or higher, no problem occurs even if only map information of level 1 or higher is updated. Therefore, in the present invention, only the map information of level 1 or higher is changed. In this way, the number of changed portions can be reduced by about 90%, and a seamless route guidance can be performed at a low cost using the latest map information. In addition, the amount of difference data can be reduced to such an extent that a nationwide map update can be performed at once.
[0008]
At the time of actual map display, road images are generated based on the level 0 road information and the level 1 road information, respectively, and the respective road images are superimposed and displayed. As a result, the narrow streets are obsolete, but the roads of level 1 or more that are truly necessary during driving can be correctly displayed.
In addition, a departure point on a level 1 road, a route from a destination to a point on a level 2 road, and a path from a level 2 point to a point on a higher level road are appropriately searched for and a search is performed from the departure point to the destination. A route to the ground is searched, the searched route information of level 1 or higher is converted into level 1 route information, and a searched route is drawn using the level 1 road information. Thus, the route search and the route display at the level 1 can be performed.
Since narrow streets have become obsolete, as in the past, the search for narrow streets from the starting point on the narrow street to the level 1 near the departure point and the destination, and the purpose on the narrow street from the point on the level 1 road. A narrow street search is not performed because a narrow street search to the ground may be erroneous.
An enlarged view of an intersection is displayed when approaching an intersection. Conventionally, an enlarged view of an intersection is created and displayed using map information of level 0. In the present invention, since the map information of level 0 cannot be used, a large number of intersection shape patterns (including the traveling direction arrows) are prepared in advance in a deformed manner, and an intersection enlarged pattern is prepared by using which intersection shape pattern in the intersection information. Enlarged view instruction data indicating whether to display is added. Thereby, the intersection enlarged view indicated by the enlarged view instruction data is drawn.
Conventionally, map matching is performed using level 0 map information, but in the present invention, map matching processing is performed using level 0 and level 1 map information. When the point on the level 1 road is a candidate point for the map matching process, the current position is corrected to the candidate point for the map matching process, and the point on the level 0 road is set as the candidate point for the map matching process. If so, it is determined that the vehicle is off route.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
(A) Level Configuration of Map Information FIG. 1 is an explanatory diagram of levels of map information according to the present invention, in which levels are 0 to 3. Level 0 is a dedicated level for non-guided roads (small streets of 5.5 m or less) that are not used for route search. Level 1 is a level that includes all guidance target roads other than non-guide target roads. Level 2 is a level that includes roads whose width is equal to or greater than the first set length. Level 3 is a road whose width is equal to or greater than the second set length. , Including toll roads.
[0010]
(B) Correspondence between Functions Performed at Conventional Level 0 and Levels of the Present Invention FIG. 2 is a correspondence diagram between functions performed at conventional level 0 and levels according to the present invention.
Map drawing The map drawing is performed by generating road images based on the level 0 road information and the level 1 road information, and displaying the respective road images in a superimposed manner.
Route drawing A route from a starting point on a level 1 road, a destination to a point on a level 2 road, and a route from a level 2 point to a point on a higher level road are appropriately searched from the starting point. Find a route to your destination. Thereafter, the searched route information of level 1 or higher is converted into level 1 route information, and the searched route is drawn using the level 1 road information.
[0011]
・ Narrow street search No narrow street search is performed.
Intersection route guidance A large number of intersection shape patterns (including the traveling direction arrows) are prepared in advance in a deformed manner, and as shown in FIG. 3A, an intersection enlarged pattern using which intersection shape pattern is used for the intersection information CPI. Is displayed, and the enlarged intersection map is drawn as shown in FIG. 9C using the vector data (b) indicated by the enlarged map instruction data ELP of the approaching intersection. .
-Map matching processing The map matching processing is performed using the map information of level 0 and level 1. If the point on the road of level 1 is a candidate point of the map matching processing, the candidate point of the map matching processing is The position is corrected, and if the point on the level 0 road is a candidate point for the map matching processing, it is determined that the vehicle is off-route.
[0012]
(C) Configuration of the Navigation Device of the Present Invention FIG. 4 is a configuration diagram of the HDD navigation device of the present invention, wherein 1 is a navigation control device, 2 is a remote controller, 3 is a display device (color monitor), 4a is a hard disk (HDD), 4b is an HDD control device, 5 is a communication interface, 6 is a multi-beam antenna, 7 is a GPS receiver, 8 is a self-contained navigation sensor, and 9 is an audio unit. The self-contained navigation sensor 8 includes a relative azimuth sensor (angle sensor) 8a such as a vibrating gyroscope that detects a vehicle rotation angle, and a distance sensor 8b that generates one pulse for each predetermined traveling distance.
[0013]
In the navigation control device 1, reference numeral 11 denotes a map reading control unit. {Circle around (1)} When a map movement operation or a map selection operation is performed using a joystick key, a map reduction / enlargement key, or the like, a focus position (a latitude / longitude position at the center of the screen). ), And (2) reads out predetermined map information from the HDD 4a by controlling the HDD control device 4b based on the vehicle position or the focus position. Reference numeral 12 denotes a map buffer for storing map information read from the HDD. In the map buffer, map information of a plurality of sheets (a plurality of units) around the own vehicle position or the focus position, for example, map information of 3 × 3 units is read so that the map can be scrolled.
Reference numeral 13 denotes a map drawing unit which generates a map image using map information stored in the map buffer 12, 14 denotes a VRAM for storing the map image, and 15 denotes a screen center position (own vehicle position, focus position). This is a reading control unit that changes the position of one screen cut out from the VRAM 14 based on the VRAM 14 and scrolls and displays the map according to the movement of the vehicle position or the focus movement.
[0014]
Reference numeral 16 denotes an intersection guide unit that provides guidance at the approaching intersection by a display image and a voice. When an own vehicle approaches within a predetermined distance from the approaching intersection during actual route guidance, the intersection guide map (intersection enlarged view, A traveling direction arrow) is displayed on the display screen and the traveling direction is guided by voice. Reference numeral 17 denotes a remote control unit that receives signals according to the operation of the remote controller and instructs each unit, 18 denotes a GPS data storage unit that stores GPS data from a GPS receiver, and 19 denotes a position of the vehicle based on an output of a self-contained navigation sensor. (Estimated vehicle position), a vehicle position / azimuth calculation unit for calculating the vehicle azimuth, 20 is a map matching control unit, and a predetermined traveling is performed using the map information read from the map buffer 12, the estimated vehicle position, and the vehicle azimuth. A map matching process by the projection method is performed for each distance (for example, 10 m) to correct the position of the own vehicle on the traveling road. When a candidate point by the map matching process exists on a road on level 0, the map matching control unit 20 outputs an off-route signal on the assumption that the vehicle has deviated from the guidance route.
[0015]
A guidance route control unit 21 performs a calculation process of a guidance route (search route) from the input departure point to the destination, and performs a route search process when a vehicle deviates from the guidance route (off route). 22 is a guidance route memory for storing guidance routes, 23 is a guidance route drawing unit, which reads guidance route information (node sequence) from the guidance route memory 22 and draws it on a map during traveling, and 24 denotes various menu screens An operation screen generating unit for displaying (operation screen) 25 is an image synthesizing unit.
[0016]
(D) Various Processes (a) Map Information Change Process At the time of map information change process, the HDD control device 4b connects to a center (not shown) via the communication interface 5 and requests download of the latest map information. Thus, the map information of levels 1 to 3 (in the case of FIG. 1) is downloaded from the center. The HDD control device 4b rewrites old level 1 to 3 map information with the latest downloaded level 1 to 3 map information. Thus, the map information change process is completed.
In the above example, the latest level 1 to 3 information is downloaded. However, the difference between the latest level 1 to 3 map information and the old level 1 to 3 map information is downloaded. You can also.
[0017]
(B) Map drawing FIG. 5 is a map drawing processing flow. At the time of the map drawing process, the map drawing unit 13 generates a narrow street image using the level 0 map information and stores it in the VRAM 14 (step 101). An image is generated and stored in the VRAM 14 (step 102). As a result, as shown in FIG. 6, the narrow street at level 0 and the other road images at level 1 are superimposed on the VRAM to become a conventional level 0 road image. The read control unit 15 reads a map image around the own vehicle position from the VRAM and displays the map image (step 103).
[0018]
(C) Drawing Route FIG. 7 is a drawing process flow of a search route.
When the route search is instructed, the guide route control unit 21 performs a route search using the map data of level 1 or higher (step 201). When the route search is completed (step 202), the guide routes of levels 1 to 3 are performed. The data is converted into level 1 route data and stored in the guide route memory 22 (step 203). Next, the guide route drawing unit 23 displays the guide route on the map using the level 1 guide route data obtained by the conversion (step 204).
[0019]
(D) Enlarged intersection display FIG. 8 is an intersection enlarged view display processing flow.
The intersection shape pattern (including the traveling direction arrow) is deformed in advance and included in the map information (step 301), and the intersection shape pointer ELP is included in the intersection information (see FIG. 3, step 302).
The intersection guide unit 16 monitors whether the vehicle approaches the intersection while traveling along the guidance route (step 303), and when approaching, displays the deformed enlarged view of the intersection corresponding to the approaching intersection to provide guidance. (Step 304). Until the vehicle passes the intersection (step 305), an enlarged view of the intersection including the traveling direction is displayed. If the vehicle passes through the intersection, the drawing of the enlarged intersection is finished (step 306).
[0020]
(E) Map Matching Process FIG. 9 is a flowchart of the map matching process.
The map matching control unit 20 performs a map matching process using the level 0 map information and the level 1 map information (step 401).
It is checked whether there is a candidate on the level 1 road by the map matching process (step 402). If there is a candidate, an optimum candidate is obtained from the candidates on the level 1 road (step 403). Position correction and display position correction are performed (step 404).
On the other hand, in step 402, when there is no candidate on the level 1 road and there is a candidate on the level 0 road, it is considered that the vehicle is off-route and the off-route is notified to the guidance route control unit 21. (Step 405).
In step 402, it is checked whether (1) the best candidate exists on the level 1 road or the best candidate exists on the level 0 road, and (2) the best candidate exists on the level 1 road. In this case, the position is corrected, and (3) when the optimal candidate is present on the level 0 road, it is considered that the vehicle is off-route and the off-route is notified to the guidance route control unit 21. it can.
[0021]
【The invention's effect】
As described above, according to the present invention, only the map information of level 1 or higher is changed, so that seamless route guidance can be performed using the latest map information at a low cost without purchasing the latest disc. it can.
Further, according to the present invention, since the level 0 map information is not changed, the amount of change can be reduced, and therefore, the cost of manually creating a new and old connection relationship list when a partial update is performed can be reduced. .
Further, according to the present invention, the same navigation function as that of the related art can be realized without updating a narrow street (non-guide target road) having a high update ratio.
Further, according to the present invention, the difference data amount can be reduced by 90% by not performing the narrow street update.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a level of map information according to the present invention.
FIG. 2 is a diagram showing a correspondence relationship between a function performed at a conventional level 0 and a level according to the present invention.
FIG. 3 is an explanatory diagram in the case where intersection information is included in intersection information.
FIG. 4 is a configuration diagram of an HDD navigation device of the present invention.
FIG. 5 is a flowchart of a map drawing process.
FIG. 6 is an example of overlapping drawing.
FIG. 7 is a drawing processing flow of a search route.
FIG. 8 is an intersection enlarged view display processing flow.
FIG. 9 is a flowchart of a map matching process.
FIG. 10 is a schematic explanatory diagram of a route search process using map data having a hierarchical structure.
FIG. 11 is a conventional map information explanatory diagram of levels 0 to 3.
FIG. 12 is an explanatory diagram of a function using current level 0 data.
[Explanation of symbols]
1 Navigation control device 4a Hard disk (HDD)
4b HDD control device 13 map drawing unit 14 VRAM
16 intersection guidance unit 20 map matching control unit 21 guidance route control unit

Claims (5)

Map information is composed of multiple levels,
Level 0 is a dedicated level for non-guided roads not used for route search, Level 1 is a level for guided roads other than non-guided roads,
When changing map information, change only map information of level 1 or higher,
A map information changing method, characterized in that: A map recording medium having map information in which level 0 is a dedicated level of a non-guided road not used for route search and level 1 is a level of a guided road other than the non-guided road;
A road image generation unit that generates a road image based on the level 0 road information and the level 1 road information when displaying the road;
A display unit that displays each road image superimposed,
A navigation device comprising: From the departure point to the destination, search for the departure point on the level 1 road, the route from the destination to the point on the higher level road, and the route from the higher level point to the point on the higher level road as appropriate. Route search means for searching for a route of
Search route drawing means for converting the searched route information of level 1 or higher into route information of level 1 and drawing a search route using the converted level 1 road information;
The navigation device according to claim 2, further comprising: A large number of intersection shape patterns are deformed and prepared in advance, and enlarged view instruction data indicating which intersection shape pattern is to be used to display the enlarged view of the intersection is added to the intersection information. Intersection enlarged view drawing means for drawing an intersection enlarged view to be instructed,
The navigation device according to claim 2, further comprising: A map matching process is performed using the level 0 and level 1 map information. If a point on the level 1 road is a candidate point for the map matching process, the current position is corrected to the candidate point for the map matching process. If the point on the road 0 is a candidate point for the map matching process, a map matching processing unit that determines that the route is off route;
The navigation device according to claim 2, further comprising:

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