JPS59164583A - Map display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a map display device that is capable of expanding the range of a displayed map and reducing the capacity of map data while providing flexibility in display form. .

Recently, devices have been developed that display maps for driving guidance on vehicles such as automobiles. Conventionally, this type of map display device usually has individual map data for each map to be displayed, and sets the area of the displayed map to be wide while preserving details, and also adjusts the displayed map as necessary. In order to provide flexibility in the display format by enlarging or reducing the map data, the overall capacity of the map data increases, which leads to an increase in the size of the map data storage medium.On the other hand, if the capacity of the map data is restricted, the display This tends to cause problems such as the overall range of the map becoming narrower and lack of detail.

The present invention is based on the above points, and its main purpose is to expand the range of the displayed map and reduce the size of the map data, while providing flexibility in display format. The purpose is to also make 1=.

Therefore, as shown in FIG. 1, the present invention includes a display 1 on which a map is displayed, a map having a point information string representing each point on the map in spherical coordinates or orthogonal coordinates with respect to a specific point, and level information. a data storage medium 2; a switching means 3 for switching display modes regarding the scale or density of the displayed map; Comprising an extraction means 4 for extracting from a point information string, and a coordinate conversion means 5 for converting the M coordinates of the points extracted by the extraction means 4 into display coordinates, displaying the map according to a specified scale or density. It is characterized by being able to change its shape. Hereinafter, one embodiment of the present invention will be described with reference to the drawings from FIG. 2 onwards.

FIG. 2 shows a block diagram of this embodiment.

In the figure, 7 is an operation unit which has the function of the switching means 3 and is operated by the driver etc. when using the travel guidance system, 8 is an azimuth sensor,
9 is a distance sensor that detects the traveling direction of the vehicle, that is, the geomagnetic direction with respect to the float; 2 is a map data storage medium that detects the traveling distance of the vehicle, and pre-stores predetermined map data. , 10 is a control device;
It is equipped with a microcomputer 10-1 consisting of CPU ROM, RAM, Ilo, etc. and a display controller 10-2, and functionally executes arithmetic processing and display controllers 1 to 1. 1 is a display, on which at least a map is displayed. Each represents something.

The operation unit 7 has an enlargement key for instructing to enlarge the currently displayed map by one rank, a reduction key for reducing the currently displayed map by one rank, and a reduction key for making the currently displayed map sparse by one rank. and a dense key to make the currently displayed map one rank denser.

The orientation sensor 8 includes a ring-shaped permalloy core, an excitation coil, and two coils that are perpendicular to each other, and controls an orientation signal for detecting the direction of travel of the vehicle with respect to the earth's magnetic field based on the output voltages of these two coils. Output to the device 10.

The distance sensor 9 indirectly detects the rotation of the speedometer cable as an electrical signal using a reed switch, a magnetically sensitive element, or a photoelectric conversion element, or detects the rotation of the output shaft of the transmission as an electrical signal using the same means as described above. , outputs a distance signal to the control device 10, which is used in calculating the travel distance of the vehicle.

The map data storage medium 2 is a ROM (Read Only
Memory) consists of packages. The data structure of the map data stored in advance in the map data storage medium 2 includes, for example, as shown in FIG. , an information column 13 for rules 1 regarding routes such as national highways, and an article information column 14 regarding various routes and services.
It consists of The point information string 12 includes a group of point information strings for prefectures belonging to the region, such as the Aichi prefecture point information string 15 for Aichi Prefecture. It has a city point information string group of cities belonging to the prefecture, such as Nagoya cloth point information string 16 for Nagoya City, which belongs to the prefecture, and among the city point information string group, for example, Nagoya cloth point information string 16 is a major place belonging to Nagoya City. It has a point information group consisting of point information 17-1, 17-2, . X component, Y
Consists of component information. The route information string 13 includes #1 route information string 18-1, #2 route information string 18-2, . . . , #
N route information strings 18-N and these route information strings 18-
Consisting of pointers 19-1.19-2, ..., 19-N that correspond one-to-one to 1.18-2, ..., 18-N, each route information string 18-1.18- 2,...,18
~N consists of a route number, a route level, a route type, a group of point numbers for points forming the route, and the end of the route. Article information column 14 is intersection name information column 201
, route name information string 20-2, . . . , landmark name information string 20-M, and these name information strings 20-1, 20-2, .
. . , a pointer 21-1 that corresponds one-to-one to 20-M.
21-2, ..., 21-M, and the intersection name information column 20-1 is intersection information consisting of point number, name level, intersection name intersection information 21-1, 21-2, ... The route name information string 20-2 includes route information 22-1.22 of route number, name level, and route name.
-2, ..., and the landmark name information string 20-M is landmark information consisting of point number, name level, landmark information 23-1, 23-2, ... of the landmark name. have a group.

Here, the above route type represents the type of route such as national highway, expressway, general road, railway, coastline, etc., and the above point type refers to general intersection, grade-level intersection of general road, interchange, general road, etc. This indicates the type of point, such as an intersection with an expressway or an intersection between a general road and a railway.

The control device 10 receives instruction signals from the operation unit 7 and the direction sensor 8.
Upon receiving the azimuth signal from the azimuth sensor, the distance signal from the distance sensor 9, and the map data from the terrain data storage medium 2, it executes predetermined processing as described later in FIG. 6, controls the display 1, and outputs the video signal. is output to the display 6.

Display 1 is a CRT (Cathode Ray).
A map and the like are displayed on the display screen using a video signal from the control device 10.

In the above configuration, the relationship between the level information in the map data on the map data storage medium 2 and the size specified by key operation is as shown in the following table (a).

Table (A) Specifically, when the size O corresponding to the scale of 1/1 million is specified by operating the enlargement key or reduction key, only routes and points for which rOJ is given as level information in advance are displayed. When a size 1 corresponding to a scale of 1/500,000 is specified, the relationship between the size and level of routes and points whose level information is ``0'' or ``1'' is specified. is as shown in the table (a) above, but when a sparse key or a dense key is operated, the relationship between the two is changed as shown in the following table (b) and (c) by one operation of each key. Updated.

Table 85 (b) corresponds to the case where the secret key is operated once.

Table (B) Table (C) To be more specific, for example, when a sparse key is operated once when a map corresponding to size 3 is currently being displayed, the level changes to "0", "1" and so on. , "2", "3"
Points or routes that had any of the above were displayed, but now points or routes that have the level rOJ, "1", or "2" are displayed.
Therefore, level 3 points or routes are excluded from display targets, and the displayed map becomes sparse. On the other hand, similarly size 3
When the specified map is displayed, the secret key is 1
When the operation is performed twice, a new level "4" point or route is added to the display target, and the displayed map becomes denser.

Next, an example of the transition of the display format of the display 1 will be described with reference to FIGS. 4a to 4C and FIGS. 5a to 5C.

When it is specified by the operator's key operation or the internal processing of the control device 10 that the displayed map should be enlarged, for example, the fourth
Assuming that a map as shown in FIG. 4A is displayed, the control device 10 executes an enlargement process for the area A surrounded by the broken line in FIG. It should be relatively detailed. After that, when further enlargement is specified, the enlarging process for the broken line enclosing area B in FIG. 4B is executed, and a more detailed map as shown in FIG. 4C is displayed on the display 1 screen. Make it. still,
Points a and b in Figure 4a represent the same points as points a and b in Figure 4b, respectively.
Points a through h represent the same points as points a through 11 in FIG. 4C, respectively.

On the other hand, when it is specified that the displayed map should be reduced, a transition in the display form is performed that is opposite to the transition in the display form caused by the enlargement process as described above. That is, the displayed map shown in FIG. 4C is changed to the displayed map shown in FIG. 4b, and further to the displayed map shown in FIG. 4a.

Further, when it is specified that the displayed map should be made denser by the operator's key operation or by the internal processing of the control device 10, if the map shown in FIG. 5a is currently being displayed, the control device 10 Densification processing is executed so that a relatively detailed map as shown in FIG. 5b, for example, is displayed on one display screen. After that, when further densification is specified, further densification processing is executed, for example, the 5th C
A more detailed map as shown in the figure is displayed. Note that points a' to 9' in Figure $5a represent the same points as points a' to g' in Figure 5b, respectively, and points a' to 0' in Figure 5b represent the same points as points a' to g' in Figure 5b, respectively.
This represents the same point as points a' to θ' in diagram C.

On the other hand, when it is specified that the displayed map should be made sparse, a transition in the display format is made that is opposite to the transition of the display form due to the densification process as described above. That is, the displayed map shown in FIG. 5C is changed to the displayed map shown in FIG. 5b, and further to the displayed map shown in FIG. 5a.

Next, the processing operation of this embodiment will be explained with reference to the schematic flowchart shown in FIG. Note that the following explanation will be given by taking as an example a case where enlargement is specified by an operator's key operation.

When the operator operates the enlargement key of the operation section 7, the control device B1
The microcomputer 1o-1 of No. 0 starts processing as shown in FIG.

First, step 101 is executed and the map data storage medium 2 is
The contents of the first pointer 1 in the rule 1-information string 13 are read.

Next, step 102 is executed to determine whether the contents of all pointers 19-1 to 19-N have been read.

At this point, the contents of the head pointer 19-1 have just been read, so the determination result is "NO" and step 103 is then executed.

In step 103, the #i route information string (#1
The level information is read to route 1 of the route information string 18-1). Here, the root level information can be thought of as the relative importance assigned to each route.

Next, step 104 is executed to determine whether the root level is a displayable level or not, in other words, the importance of #i root (#1 root) to be displayed for the specified size as described above is determined. Determine whether the route has the following information.

If the #i route (#1 route) is a route 1~ that does not need to be displayed, execute step 105 to update the pointer, that is, read the contents of the next pointer (#2 pointer 19-2>). Return to step 102.

On the other hand, if the #1 route (#1 route) is the route to be displayed, then step 106 is executed and the route type information of the #1 route information string (#1 route information string 18-1) is read.

Next, execute step 107 and #1 route information string (#1
The point number information (at this point, the first point number information) of the route information string 18-1) is read out.

Next, step 108 is executed and #i route information string (#1
It is determined whether the route end information of the route information string 18-1> has been read out.゛At this point, the first point number information has just been read, so the determination result is rNOJ. Next, step 109 is executed and the point in the point information sequence 12 that matches the point number (first point number) is The IC point level information given to the number is read out, and it is determined whether the point in question is a point with the highest degree of importance to be displayed for the specified size as described above.

Even if this point is not displayed, if it is a good point, the process returns to step 107 and reads out the next point number in the #i route information column #1 route information column 18-1).

On the other hand, if this point is the point to be displayed, then step 110 is executed to determine whether it is the point number extracted first in the #1 route information string (#1 route information string 18-'1). to judge.

At this point, since it is the first point number, the determination result is rYEsJ, and then steps 111 to 11
4, and calculate the earth coordinate X component and earth coordinate Y of this point.
Read out the components, convert this earth coordinate point (X, Y) to a display coordinate point (x1, Yl), and then convert it to a display coordinate point (Xl, Yl).
Find the area A to which l) belongs.

As shown in Figure 7a representing the earth coordinate system and Figure 7b representing the display coordinate system, the above coordinate conversion process begins with (1)
The shaded area that falls in the display coordinate system (Display 1
Corresponds to the map display area. )'s origin (Olo) and 1
Find (MPO3, BPO3) that corresponds to the earth coordinates (X, Y) of the earth coordinate system corresponding to pair 1, and then (2) move to the current target point from the found point (MPO8, BPO3). coordinates are converted from the earth coordinates (LP01.APO3) to a point (Xl, Yl) in the display coordinate system.

Here, the above points (MPO8, BPO8,) are obtained as follows. First, set the current location or the center point of the administrative district points (Figure 9a) in the case of administrative district designation to the display map center coordinates (MAPCENX, MA) in the earth coordinate system.
PCENY), and then this coordinate information MAPC
ENX, MAPCENY, the number of dots a and b on the map display screen of display 1 (Figure 9b), and the number of dots per unit light determined according to the specified size and size.
The points (MPO8, BPO3) are obtained from the following formula, which uses the number of dots per unit latitude, ADOT, as a parameter. and the point (X
, Y) can be found from the following formula.

The coordinates of the center point of the administrative district designation map shown in Figure 9a are:
Four points (α, β,
From the earth coordinates of γ, δ), the following formula MAPCENX= (
It is determined by: (Longitude of the east end - Longitude of the west end)/2 MAPCENY = (Latitude of the north end - Latitude of the south end)/2.

On the other hand, in the area determination process, the display coordinate point (x1, Yl) obtained by the coordinate conversion process as described above is divided as shown in FIG. − This is done by determining whether In addition, in this FIG. 8a, area IV corresponds to the diagonally shaded area shown in FIG. 7b, that is, the map display area.

Once the area A to which the display coordinate point (Xl, Yl) belongs is determined in step 114 described above, the process returns to step 107.
Read out the next point number in #i route information string (#1 route information string 18-1 >).

Next, step 108 is executed to determine whether or not the route has ended. If the route has not been completed, step 109 is then executed to determine whether or not the point level of this point number is a displayable level, and the displayable level is If not, step 107
, and if the level is displayable, then step 110 is executed, and this point number is extracted first in the #i mile-1 to route information string (#1 route information string 18-1>) and becomes the IC point. Determine whether it is a number.

At this point, since the first point number has already been extracted, the judgment result is "NO", and then steps 115 to 118 are executed sequentially, and the same processing as steps 111 to 114 is performed. Processing takes place. In other words, the earth coordinates (X
, Y) to display coordinates (X2, Y2), and find the region B to which the display coordinates (X2, Y2> belong).

Next, step 119 is executed, and the point (Xl, Yl) and the point (
It is determined whether or not to perform a connected display with X2, Y2>, that is, whether or not the area A and the area B have a specific relationship. Here, as shown in FIGS. 8a and 8b, this judgment process is performed, for example, when the display coordinates (Xl, Yl) are
belongs to the area and other display coordinates (X2, Y2) are 0th,
If it belongs to any of the engineering, ■, ■, and Vl regions, there is no specific relationship (indicated by an X in FIG. 8b).

), the display coordinates (×1, Yl) belong to the Oth area, and the other display coordinates (X2, Y2) belong to the rv, v,
If it belongs to either the vn or ■ area, it is determined that there is a specific relationship (indicated by a circle in FIG. 8b). Other combinations are as shown in FIG. 8b.

If region A and region B do not have a specific relationship, then steps 120 to 121 are executed, and flJ region update processing and coordinates (Xl, Yl) are performed to set region A as region B.
A coordinate update process is performed to set (X2, Y, 2), and the process returns to step 107.

On the other hand, if there is a specific relationship, then step 122
is executed, and a connecting line between the point (x1, Yl) and the point (x2, Y2) is displayed on the display screen according to the route type. That is, for example, if #I route (#1 route) is a national highway, the route is displayed with higher brightness than other routes. Then, steps 120 and 121 are executed to perform area update processing and coordinate update processing, and the process returns to step 107.

Thereafter, until the end of route #i route (#1 route) is read, the route consisting of steps 107, 108, 109, or steps 107.1O8, 109t/',
7. One of the routes consisting of 110.

Then, when the end of route #i route (#1 route) is read out, the determination result in step 108 is reversed to rYEsJ, so step 1.5 is executed to update the pointer, and the next route ( The processing for route #2) is performed in the same way as the processing for route #1.

Thereafter, the same processing as described above is sequentially executed for each route information string, and when the processing for #N route information string 18-N is completed, it is determined in step 102 that the contents of all pointers have been read, and the sixth The illustrated process is completed.

As is clear from the above explanation, when the control device 1o receives an enlargement designation from the switching means, for example, the operation unit 7, the control device 1o selects a route having a level corresponding to the designation from among each route information string in the map data storage medium 2. Extract points from the route that have a level corresponding to the designation, perform coordinate transformation on the extracted points, determine whether two adjacent points have a specific relationship, and If there is a relationship, the two points are connected and displayed with brightness according to the route type.

Therefore, when the display mode is an enlargement or reduction scale mode, display patterns as shown in FIGS. 4a to 4c are displayed, whereas when the display mode is a sparse or dense mode, Display patterns such as those shown in Figures 5C to 5C can be obtained.

As explained above, in the present invention, the earth coordinates are given to the point information of the map data, and at least the level is given to the point number. Therefore, when the desired display mode is specified by the operator, the display mode is adjusted accordingly. It is possible to display a map of a high level on the display, and the data capacity is relatively small (although it is possible to have a sufficient degree of freedom in the display form).

Note that the display is not limited to a CRT, and may be a display device such as a liquid crystal EL. Furthermore, although a ROM is shown as a map data storage medium, a magnetic tape, a magnetic disk, a magnetic valve, etc. may also be used. Needless to say, in this case, a reading device is required to read the map data. Furthermore, although a direction sensor that detects earth's magnetic field is shown, a gyro type sensor that detects the relative direction of movement of the vehicle may be used.

Furthermore, in the above embodiment, the earth coordinates are given as absolute longitude and absolute latitude, but the present invention also includes cases in which the coordinates of a point are expressed as spherical coordinates for a specific point (for example, Tokyo) or orthogonal coordinates for a specific point. .

[Brief explanation of the drawing]

Figure 1 is a diagram showing the overall configuration of the present invention, Figures 2 to 8b are embodiments of the present invention, Figure 2 is a block diagram, Figure 3 is a configuration diagram of map data, and Figure 4a is a diagram showing the configuration of map data. ~Figure 4C is a diagram showing the display format when the display mode is scale mode, Figures 5a to 5C are diagrams showing the display format when the display mode is density mode, and Figure 6 is a diagram showing the processing operation. Figures 7a and 7b are flowcharts for explaining the coordinate transformation from the earth coordinate system to the display coordinate system, and Figures 8a and 8b are the connections between two points in the display coordinate system. Figures 9a and 9b, which are diagrams for explaining the distance, are the earth coordinates (MPO8,
Explanatory diagrams for explaining the method for determining BPO8) are shown. 1...Display 2...Map data storage medium 3...Switching means 4...Extracting means 5...Coordinate conversion means Agent Patent attorney Tsutomu Sateri and 1 other person Figure 7o "Figure 7b Figure 80 figure

Claims (1)

[Claims] A display on which a map is displayed, a map data storage medium having a point information string representing each point on the map in spherical coordinates or orthogonal coordinates with respect to a specific point, and also having level information; a switching means for switching the display mode regarding the scale or density of the map; and an extraction means for extracting point information corresponding to the level corresponding to the display mode designated by the switching means from the point information string as displayable points. and coordinate conversion means for converting the Sutahashi coordinates of the point extracted by the extraction means into display coordinates, and the display form of the map is changed according to the specified scale or density. map display device.