JP3514661B2 - Method and apparatus for determining presence / absence of city map in navigation device and recording medium - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted navigation device, and more particularly to a navigation device which can determine the presence / absence of a city map at the location and accurately display the city map in response to a request from a user.

[0002]

2. Description of the Related Art FIG. 1 schematically shows an example of a city map display determination method in a conventional navigation device. As shown in FIG. 1A, a road map is generally composed of a plurality of sections according to the scale. The shaded area in (a) of FIG. 1 indicates an area where a city map such as a municipality unit exists. Conventionally, as shown in FIG. 1 (b), information indicating the presence or absence of a city map is given to each screen unit of each section, and even if each section includes a part of the city area, there is a city map in the entire section. Information was given. Therefore, the city area actually obtained by surveying or the like shown in FIG. 1A has been transformed in units of sections as shown in FIG. 1B.

[0003]

As a result, when the display position moves from the point A to the point B, the city area is displayed on the display screen b'of the information and the information without the city map in the section of the point B. It was not inconsistent with each other, and there was no problem in operating the navigation device. On the other hand, when the display position moved from the point A to the point C, the information regarding the presence of the city map in the section of the point C was also related. However, there is a problem that there is no city area to be displayed on the display screen c ′ at the point C.

In this case, a "city map display button" or the like is displayed on the navigation screen of the vehicle at the point C, for example, according to the information with the city map shown in FIG. 1B. However, when the user presses the button, the navigation device tries to draw the corresponding city map, and since there is no city map in the display screen, only the background screen (blank map) is displayed. .

Therefore, an object of the present invention is to solve the above problems.
To provide a method and a device for determining presence / absence of a city map in a navigation device capable of accurately determining the presence / absence of a city map at a vehicle position and accurately (or automatically) displaying a city map at the request of a user. .

[0006]

According to the present invention, there is provided a method of determining presence / absence of a city map in a navigation device,
Providing a polygon that encloses the area of the city map, before
Area data of polygon and area data of current display screen
The polygon area in the display screen is cut by the logical product of
Calculate the area of the cut-out polygon area
The calculation of the area of the display screen area
The ratio of the area of the polygon area is calculated.
If it is larger than the specified value, it is determined that there is a city map and the city map
The ratio is smaller than a predetermined value.
If it is determined that there is no city map, it becomes impossible to display the city map.
A method for determining the presence / absence of a city map in a navigation device is provided.

Further, according to the present invention, the area where the city map exists
The polygon surrounding the area, the area data of the polygon and the current
The display image is obtained by the logical product with the area data of the display screen of
A means for cutting out a polygon area in a plane, and the cutting out
A means for calculating the area of the polygon area and the display screen area
The ratio of the calculated polygon area to the area of the area
A means for determining the result and when the ratio is larger than a predetermined value
Is a hand that makes it possible to display the city map by determining that there is a city map.
If there is a staircase and the ratio is less than the specified value, there is no city map
And a means for judging that the city map cannot be displayed, and a navigation device.

Further in accordance with the present invention, navigation
The device displays the city map at the current vehicle position or display position.
Judgment of presence / absence, city map automatically by user's instruction
Map data used to display the
Polygon data surrounding the area where the city map used for judgment exists
The navigation system that stores the map data with
A map data recording medium that can be read by
It

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows an example of the configuration of a navigation device embodying the present invention. In FIG. 2, the current position detection processing unit 16 inside the navigation device body 15 obtains the current vehicle position based on the vehicle position information provided from the GPS receiver 11, the direction sensor 12, and the vehicle speed sensor 13. The map data selection unit of the control unit 17 gives an instruction to read the map data according to the current vehicle position information. In response to the instruction, the map data read processing unit 18 reads the corresponding map data from the map data unit 14 composed of a CD-ROM or a DVD-ROM device, and temporarily stores it in the internal RAM or the like.

The RAM and the like store map data of a plurality of sections as shown in FIG. The map drawing processing unit of the control unit 17 selects a screen for displaying the position of the vehicle and performs necessary drawing processing. Display control unit 20
Displays the selected one screen on the display device 22 such as an LCD panel. On the other hand, the user uses a button, a touch panel, an input device 21 including a voice recognition device, and the like to display the display angle of the display data of the display device 22, a display position,
Various requests such as a display scale are given to the user setting information unit 19, and the control unit 17 changes the display content according to the information from the user setting information unit 19.

By the way, the configuration and operation of the above-described navigation device are general. However, according to the present invention, the map data unit 14 further has polygon data surrounding the area where the city map corresponding to each section of the map data exists. In addition, the control unit 17 accurately determines whether or not there is a city map at the current vehicle position or display position by using the polygon data, and thereby an accurate city map is displayed according to a user's instruction or automatically. To do. The detailed operation of the present invention will be described below.

FIG. 3 shows an example of city map display determination in the navigation device according to the present invention. In FIG. 3, the shaded area indicates an area where a city map such as a municipality unit exists, as in FIG. According to the present invention, polygon data composed of vector data indicating a closed area of a city area is given to each screen unit of map data.

For example, one section on the upper left side of FIG. 3 is all included in one polygon data (within a thick solid line frame), and in the one section below that, the upper half is another polygon data (within a thick solid line frame). Will have. The polygon data of the entire city map is further provided by the collection of the plurality of polygon data. In the present invention, as shown in FIG. 3, only the area in which polygon data exists is determined to have "city map".
Therefore, unlike the conventional example shown in FIG. 1 (b), the presence / absence determination of the city map is not changed for each section of the map data, and the accurate presence / absence determination of the city area actually obtained by surveying or the like is performed. Will be possible.

FIG. 4 shows a basic control flow of the method for determining presence / absence of city map according to the present invention. First, in step S101, the current vehicle position is detected. Next, in step S102, it is determined whether or not the vehicle position is within the polygonal area surrounding the area where the city map exists. Although it is considered that the vehicle position is generally set at the center of the display screen (see (a) of FIG. 1), it may be set at a predetermined place on the display screen if necessary. The step of setting the vehicle position is performed before step S101.

Next, at step S102, if the vehicle position is within the polygon area (with city map) (YES), the city map can be displayed as shown at step S104.
In FIG. 3, when the vehicle is at the point A, for example, a "city map display button" is displayed, and when the user presses the button, the city map corresponding to the navigation device is displayed.
The city map may be automatically displayed when the city map can be displayed or when the city map can be displayed by the user setting of the navigation device.

On the contrary, if the vehicle position is outside the polygon area (no city map) in step S103 (NO),
In step S105, the city map cannot be displayed. In FIG. 3, the vehicle is located at point B or C. Therefore, especially at the point C, an erroneous "city map display button" unlike the conventional example in FIG. 1 is not displayed. Further, although not shown in the flow, according to the present invention, when the state where the city map can be displayed is changed to the state where it cannot
A scale map on the wide area side, such as a detailed road map or a road map, is selected and displayed. As described above, according to the present invention, the problems such as the “erroneous display” and the “blank map display” of the conventional example can be solved and an appropriate reduced scale map can be displayed.

FIG. 5 shows another control flow example of the method for determining presence / absence of city map according to the present invention. FIG. 7 shows FIG.
6 is an explanatory diagram of a process of FIG. In FIG. 5, it is determined whether or not the city map can be properly displayed on the screen after scrolling even when the position of the vehicle does not exist on the display screen due to scrolling operation of the navigation screen. It shows a method.

In step S201, the logical product (AND) of the data of the polygon area of the city map and the data of the display screen area at that time is taken, and the polygon area in the display screen is cut out (AND). Shaded area).
Next, in step S202, an area P inside the cut-out polygon area is calculated, and in step S203, a ratio R between the area S of the display screen and the area P of the polygon inside area is obtained (for example, R = P. / S x 100
[%]).

When the ratio R is larger than the predetermined value (α) (YES; R> α), it is determined that the city map is properly displayed, and the city map can be displayed (S20).
4 and 205). On the contrary, if the ratio R is smaller than the predetermined value (α) (NO; R <α), it is determined that the display of the city map is inappropriate and the city map cannot be displayed (S204).
And 206). As an example, in the former case, the "city map display button" or the like is displayed as described above.

FIG. 6 shows, as an embodiment of the present invention, a display when a vehicle frequently goes in and out of a polygon area while traveling on a road near a polygon boundary in a city map, or when it crosses a polygon boundary. It is an example of a method of controlling the screen. FIG. 8 is an explanatory diagram of the processing of FIG. In step S301 of FIG. 6A, when the control unit 17 (FIG. 2) of the navigation device body 15 detects that the host vehicle has crossed the polygon boundary, in the next step S302, it is i) “Inside polygon area”. → out of range ”
Or ii) the movement of “outside the polygon area → inside the area”.

In the case of i) (Yes), (a) of FIG.
The polygon boundary line is contracted inward as shown in (S303). On the contrary, in the case of ii) (NO), the polygon boundary line is expanded outward as shown in FIG. 8B (S303). By these two processes, in the case of i), it takes more time to move to the next “outside of polygon area → inside area”, while in the case of ii), it takes more time to move to the next “inside polygon area → area”. Moving out will take more time.

That is, a hysteresis is given to the moving time when traversing inside and outside the polygon area. As a result, it is possible to avoid the inconvenience that the display screen of the navigation device is frequently switched while moving around the polygon boundary. This is particularly effective when the scale of the displayed map is automatically switched.

FIG. 6B shows an example of a flow for performing the control of FIG. 6A more easily. In (a) of FIG. 6, while the enlargement / reduction calculation of the polygon boundary line is involved,
In this example, when the inside and outside of the polygon area is crossed (S401),
A timer for a predetermined time, for example, several seconds to several tens of seconds is simply started, and during that time, processing for prohibiting switching of map selection is performed (S402). Then, when returning to the original area within the timer time, the selection of the display map remains unchanged. On the other hand, when the positions inside and outside the polygon boundary change at the time when the timer ends, after the timer ends, the inside and outside of the polygon boundary can be judged again (if necessary) and the selection can be switched.

[0024]

As described above, according to the present invention, it is possible to accurately determine the presence / absence of the city map at the vehicle position by using the polygon data of the city map, and it is possible to accurately determine whether or not there is a city map at the vehicle position. It becomes possible to display a city map on the.

Further, according to the present invention, even when the position of the vehicle does not exist in the display screen due to the scroll operation of the navigation screen or the like, it is possible to display an appropriate city map on the display screen after scrolling. .

Further, according to the present invention, the display screen of the navigation device is frequently switched while traveling in the vicinity of the polygon boundary by providing a hysteresis for switching the display screen when traversing inside and outside the polygon area. It can be avoided.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of city map display determination in a conventional navigation device.

FIG. 2 is a diagram showing an example of the configuration of a navigation device embodying the present invention.

FIG. 3 is a diagram showing an example of city map display determination in the navigation device according to the present invention.

FIG. 4 is a diagram showing a basic control flow of a city map presence / absence determining method according to the present invention.

FIG. 5 is a diagram showing another control flow example of the city map presence / absence determining method according to the present invention.

FIG. 6 is a diagram showing a control example of a display screen when crossing a polygon boundary.

FIG. 7 is an explanatory diagram of a process of FIG.

FIG. 8 is an explanatory diagram of a process of FIG.

[Explanation of symbols]

11 ... GPS receiver 12 ... Direction sensor 13 ... Vehicle speed sensor 14 ... Map data section 15 ... Navigation device body 16 ... Current position detection processing unit 17 ... Control unit 18 ... Map data reading processing unit 19 ... User setting information section 20 ... Display control unit 21 ... Input device 22 ... Display device

─────────────────────────────────────────────────── ─── Continued Front Page (73) Patent Holder 000005821 Matsushita Electric Industrial Co., Ltd. 1006 Kadoma, Kadoma City, Osaka Prefecture (72) Inventor Hiroshi Takeuchi 1-22 Goshodori, Hyogo-ku, Hyogo Prefecture FUJITSU TEN Incorporated (72) Inventor Masatsugu Uemura 1-22 Gosho-dori, Hyogo-ku, Kobe-shi, Hyogo Fujitsu Ten Ltd. (72) Inventor Atsushi Ichimura 1-2-2 Gosho-dori, Hyogo-ku, Kobe No. Fujitsu Ten Limited (72) Inventor Hidenobu Suzuki 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Automobile Co., Ltd. (72) Inventor Hironobu Sugimoto 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Automobile Co., Ltd. (72 ) Inventor Yasuhiro Toyama 18 Harayama, Okamachi, Okazaki-shi, Aichi 18 Aisin AW Co., Ltd. (72) Inventor Hidetoshi Fujimoto Kariya Aichi 1-chome, Showa-cho, Yokohama (72) Inventor Isao Ogawa 4-3-1 Amishimahigashi, Kohoku-ku, Yokohama-shi, Kanagawa Matsushita Communication Industrial Co., Ltd. (56) Reference JP-A-9-134123 (JP, A) JP-A-9-159481 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01C 21/00-21/36 G08G 1/0969 G09B 29/00-29 /Ten

Claims (6)

(57) [Claims] 1. A method of determining the presence / absence of a city map in a navigation device comprises providing a polygon surrounding an area in which the city map exists, and displaying the display based on a logical product of the area data of the polygon and the area data of the current display screen. Cutting out a polygon area in the screen, calculating the area of the cut-out polygon area, obtaining a ratio of the calculated area of the polygon area to the area of the display screen area, and when the ratio is larger than a predetermined value, , It is possible to display the city map when it is determined that there is a city map, and when the ratio is smaller than a predetermined value, it is determined that there is no city map and the city map cannot be displayed. A method for determining the presence or absence of a city map in a characteristic navigation device. 2. When the display of the city map is disabled, a reduced scale map of a wider area than the city map is displayed.
The method described. 3. A method of determining presence / absence of a city map in a navigation device includes: providing a polygon surrounding an area where the city map exists; determining a vehicle position; and determining whether the vehicle position is within the polygon area. Comparing and determining, when the vehicle position is located in the polygon area,
When it is determined that there is a city map and it is possible to display the city map, when the vehicle position is located outside the polygon area,
Determining that there is no city map and disabling the display of the city map; detecting that the vehicle position has moved across a polygon boundary; detecting the movement from within the polygon area to outside the area If the detected movement is from outside the polygon area to within the area, the polygon boundary is expanded to the outside. A method for determining presence / absence of city map in a navigation device, characterized in that the presence / absence of city map determination in (1) is provided with a hysteresis. 4. A method of determining presence / absence of a city map in a navigation device includes: providing a polygon surrounding an area where a city map exists; determining a vehicle position; and determining whether the vehicle position is within the polygon area. Comparing and determining, when the vehicle position is located in the polygon area,
When it is determined that there is a city map and it is possible to display the city map, when the vehicle position is located outside the polygon area,
Determining that there is no city map and making it impossible to display the city map; detecting that the vehicle position has moved across a polygon boundary; and starting a timer for a predetermined time by detecting the movement. The method for determining the presence / absence of a city map in a navigation device, comprising: enabling a screen display according to each destination within or outside the polygon area at the end of the timer. 5. A means for cutting out a polygon area in the display screen by a logical product of a polygon surrounding an area where a city map exists and area data of the polygon and area data of the current display screen, and the cutting out. Means for calculating the area of the polygon area, means for obtaining the ratio of the calculated area of the polygon area to the area of the display screen area, and if the ratio is greater than a predetermined value, it is determined that there is a city map And a means for displaying the city map when the ratio is smaller than a predetermined value and determining that the city map is not displayed. 6. The navigation device displays the current vehicle position.
Or, determine whether there is a city map at the display position and ask if the user
For displaying the city map automatically or according to the instructions from
AreStore map data, The navigation device
ReadableIn the recording medium, A polygon surrounding the area where the city map exists, The area data of the polygon and the area data of the current display screen
Data and the polygon area in the display screen
A function to cut out, A function to calculate the area of the cut polygon area, The calculated polygon for the area of the display screen area
A function to calculate the area ratio of the area, If the ratio is greater than the specified value, it is determined that there is a city map.
And the function that enables the display of city maps, If the ratio is less than the specified value, it is determined that there is no city map.
And the function that makes it impossible to display the city map
Data and programs for storing
A recording medium readable by the navigation device.