JPH07286857A - Map displaying device - Google Patents

Abstract

PURPOSE:To expand or change the displaying extent of a map in the advancing direction of a vehicle without changing the scale of the map by generating displaying data by reading out map information from a map storing means and referring to coordinate information. CONSTITUTION:A location detecting means 2 is provided with an azimuth storing means 22 which is composed of a GPS receiver for detecting the location of its own vehicle, a vehicle speed and azimuth detector or a geomagnetism detector, etc., and calculates the advancing direction of the vehicle from the variation of the current location of the vehicle and stores the data related to the advancing direction as azimuth information. A control means 3 generates displaying data by reading out map data from a map storing means 1 and referring to coordinate information in a location storing means 21 and, at the same time, controls the map storing means 1, an inputting means 4, the location detecting means 2, and a displaying means 5. When the coordinate information does not correspond to the center or its vicinity of the screen of the displaying means 5 at the time of generating the displaying data, the control means 3 expands the displaying extent by moving the displaying coordinates of the coordinate information on the screen in response to the azimuth information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a map display device suitable for displaying the present position of a vehicle on a map.

[0002]

2. Description of the Related Art In recent years, a road map or the like has been stored in a CD-ROM or the like as digital signal information, and this has been disclosed in Japanese Patent Laid-Open No. 63-3.
As disclosed in Japanese Patent No. 05210, a map is displayed on the screen using a display means such as a television receiver. In this case, the position of the own vehicle is arranged at the center of the display screen so that maps on all four sides are displayed, and the display range can be changed by displaying the map at multiple scales.

[0003]

However, since the display means has only a small display screen of about 2 to 6 inches, only the map needs to be reduced when the user wants to know the state slightly ahead of the traveling direction. So it's hard to see.
Therefore, an attempt has been made to arrange the position of the own vehicle at the lower end of the screen to expand the display range in one direction, but this time, because the back side of the own vehicle cannot be confirmed, it may occur when the road is meandering. , It was inconvenient when there was a landmark building on the back side.

[0004]

The present invention has been made in consideration of the above points, and includes a map storage means for storing map information, a position storage means for storing coordinate information of the current position, and a map storage means. It has a control means for reading map information from the device and generating display data by referring to the coordinate information, a display means for displaying by the display data, and an input means for the display position, and the control means is for generating the display data. The display information is generated by making the coordinate information correspond to substantially the center of the screen of the display means, and the display coordinates of the coordinate information on the screen are moved in response to the operation time of the input means.

Further, the present invention has a position detecting means for detecting coordinate information of the current position and azimuth information concerning the traveling direction, and the control means generates the display data, the coordinate information being substantially at the center of the screen of the display means. When it does not correspond to, the display coordinates of the coordinate information on the screen are moved in response to the azimuth information.

[0006]

With this, the display range of the map with respect to the traveling direction can be arbitrarily enlarged without changing the scale, or the display range of the map is changed according to the change of the traveling direction while the display range is enlarged.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a map display device according to an embodiment of the present invention, taking a navigation device for an automobile as an example. In the figure, reference numeral 1 is a map storage means for storing map information, for example, information on a map of Japan is classified into road / region information by scale.
RO for storing and reproducing digitalized data such as character information such as place names and color data attached to these information
It consists of M board, CD-ROM player, ISDN communication terminal, etc.

Reference numeral 2 is a position detecting means for detecting the coordinate information of the current position and the azimuth information concerning the traveling direction, which comprises a GPS receiver for detecting the position of the vehicle, a vehicle speed azimuth detector, a geomagnetic detector, etc. It has a position storage means 21 for storing the coordinate information of the vehicle and a direction storage means 22 for calculating the traveling direction of the vehicle based on the change of the current position and storing the information on the traveling direction as the direction information. .
If necessary, these storage means 21 and 22 and the position / orientation calculation means may be included in the control means described later.

Reference numeral 3 is a control means for reading the map information from the map storage means 1 and referring to the coordinate information of the position storage means 21 to generate display data. The map storage means 1, the input means 4, the position detection means 2, and the display means. 5, etc. are controlled. The control means 3 stacks the CPU 31, the CPU operation program and fixed display data, the data necessary for the operation of the CPU 31, and stores the scale and color data which are the initial information of the map storage means 1 or the current value. Memory 32, VR for storing display dot data for about 10 screens
An AM / display control CPU for display control, an image control means 33 including a DA converter with a color palette, and the like, and an I / I for exchanging data with the map storage means 1, the input means 3, the detection means 4, etc. as necessary. It has an O port, a buffer register, etc. (none of which are shown).
In addition, as will be described later, the control means 3 normally causes the coordinate information to correspond to the approximate center of the screen of the display means to generate the display data, and responds to the operation time of the input means 4. The coordinate displayed on the screen of the coordinate information is moved downward, for example, or when the coordinate information does not correspond to the approximate center of the screen of the display means in generating the display data, the coordinate information is transmitted in response to the azimuth information. The display coordinates on the screen are moved, for example, in the direction opposite to the traveling direction of the own vehicle, so that the display position of the map relatively moves and the display range in the traveling direction is expanded.

Reference numeral 4 is a cursor key 41, a function key 42, an audio key 43, or a current value key 44.
It is used for inputting information such as mode switching, inputting information corresponding to map information, and using for an operation other than so-called navigation by an input means having such as. 5 is
It is a display means for displaying according to display data, and is composed of a TFT color liquid crystal module or the like, has a built-in liquid crystal panel, an analog liquid crystal driver, etc., and may include an interface for a television received image, etc., if necessary.

In the above-mentioned configuration, the CPU 31 operates according to the program stored in the ROM of the memory 32. However, in the case of a navigation device capable of controlling a television or audio equipment, it is used before the power is turned off when the power is turned on. When the function key assigned to the mode selection is selected and the input means 4 is monitored, a predetermined function such as television, audio equipment, navigation or the like is activated. If there is no mode used before the power is cut off, a predetermined function is selected. In each mode, the meaning of the function keys changes in order to reduce the number of keys of the input means 4, but it is possible to display a menu in which a plurality of different functions can be selected by operating a specific key. To explain the navigation operation as an example, in the normal state where the input means 4 is not operated, the CP
U31 reads the coordinate information from the position storage means 21 of the position detection means 2, or determines the current value based on the output of the position detection means, calculates the coordinate information corresponding to the current value, and stores it in the position storage means. The map information according to the coordinate information, which is the current value, is read from the map storage means 1, display data is generated, and written in the VRAM of the image control means 33. V
Since the RAM can store a plurality of screens for display as described above, the central portion is selected by the built-in output port and displayed on the display means 5 in principle, but the display portion is shifted due to movement of the cursor or movement of the current value. To be done. When a specific key is operated in such a state, a function selection menu such as "Map search", "Destination travel" or "Initial setting" is displayed. When the setting is selected, submenus such as "navigation mode setting", "voice recognition registration", and "map background color setting" are displayed. By selecting this again, each function is selected and executed.

Since the present invention relates to the setting of the display area in the navigation using the map information, the navigation operation for displaying the current value and displaying the map will be described below with reference to FIG.

First, it is assumed that the current position is x degrees east longitude and y degrees north latitude, and the map information includes a map including coordinates (x, y) and a map around the map. Therefore, for example, if one piece of map information includes a range of longitude X and latitude Y,
The map in the range of (3X, 3Y) is stored in the VRAM of the image control means 33. Further, if the display screen of the display means 5 is expressed by coordinates and the display center part changes by (10, 0) vertical and horizontal directions by +10 to -10, the upper left of the screen becomes (-10, +10), which is the bottom of the screen. The central portion of the side is (0, -10). The coordinates of the current position on the display screen (current value display coordinates) are managed by S in the following example.

In these situations, in the navigation mode, in the initial state or in the normal state, the control means 3 generates the display data by making the coordinate information correspond to the approximate center of the screen of the display means when generating the display data. Therefore, S is set to (0, 0) (see FIG. 4). Next, the position detecting means 2 determines the current value and the azimuth, and the position seating table information and the azimuth information are stored in the position storing means 21 and the azimuth storing means 22. As described above, these pieces of information may be directly calculated by the control unit 3 without being judged by the position detection unit 2 as described above. CPU of control means 3
31 reads the map information from the map storage means 1 based on this coordinate information and stores it in the image control means. In the storage, the display data is generated so that the map including the current position is located at the center in consideration of the area boundary information, the color code and the font data, and is expanded in the VRAM in the form of dot information.

Next, the address on the VRAM at which the reading of the display data is started is determined. This is done by associating the current position coordinates (x, y) with the display coordinates S (0, 0) and displaying the coordinates S (-10). , +10), and the display start address is set so that a fixed area corresponding to one display screen is read from the address on the VRAM corresponding to the position coordinate. For example, if the map size is the same as the display screen and the current position coordinates are in the center of the map, the first address of the map is set as the display start address. When the current position moves, the display head address moves, and the display data read area also moves. Therefore, for the observer, the current position is fixed at the center of the screen and the map scrolls.

At this time, frame determination is performed. This frame determination is to confirm that the display data covers the display area. For example, when the current position is located in the approximate center of the read map and the size of the display screen is substantially equal to or smaller than the size of the map, the display data can cover the entire display area, and there is no problem. On the other hand, as the current position moves, the current position coordinates move closer to the edge of the map located at the edge, and the display data that fits in the display area is lost. In such a case, the map information is read again from the map storage means 1 and the display data is regenerated so that the moved current position coordinates are contained in the map located at the center of the read map. is there.

When the display data is generated, the display start address is determined, and the frame is determined in this manner, the display means 5 displays the data. If S is (0,0), the current position is located at the center of the display. Input means 4 at this time
When the present value key 44 is operated for a certain time (one second or more in FIG. 4), the control means 3 moves the display coordinates of the coordinate information on the screen in response to the operation time of the input means. Specifically, t is counted up every 0.5 seconds, and the elapsed time is used as it is as the downward display coordinate from the center. Therefore, for example, if the button is pressed for 3 seconds, the current position display coordinate S becomes (0, -6), and the current position is slightly lowered and displayed as shown in FIG. 2a. If t is counted up to 10 when the operation is continued for 5 seconds or more, S =
Since it is (0, -10), the current position is the lowest, and
The whole screen is a one-way map display like. In the flowchart of FIG. 4, when the current position key 44 is pressed for a short time, S = (0,0) is restored. Note that instead of using the value of the clock counter t as it is,
The display coordinates may be used as a predetermined function value of the time counter.

When the coordinate information of the current location does not correspond to the approximate center of the screen of the display means, the control means moves the display coordinate of the coordinate information on the screen in response to the direction information in generating the display data. Let This is to round the azimuth information of the position detecting means 2 by 45 degrees and compare it with the position coordinates of the display. Apply.
That is, the upper side of the map is expressed as +1, the right side is expressed as +3, and the lower side is expressed as -1. As a result, the display orientation is displayed coordinate (0,-
5), (1, -10), etc. become -1, and the azimuth rounding value becomes +3 when heading to the right and -3 when heading to the left. Therefore, if the host vehicle is heading to the right of the screen when S = (0, −10) as shown in FIG.
3, S1 is -1, so they do not match, and S1 is G
The result of substituting the value of
S = (-10,0). As a result, as shown in FIG. 3, the current value is at the left end of the screen and the traveling direction is displayed broadly. The reason why the conversion of the current value is 45 degrees is because it is difficult to see if the direction of the map or the current value changes frequently.
If the current position is changed when traveling toward the same azimuth for more than a minute, or if the azimuth is sampled with time dispersion, 5
If the azimuth is the same in four or more times of the samples of the times, the current value may be converted.

[0019]

As described above, according to the present invention, the user can expand the display range of the map in the traveling direction without changing the scale according to his or her own preference, or proceed with the display range expanded. Since the display range of the map is changed according to the change in direction, even if there is a mark behind the vehicle, it is possible to display the traveling direction widely while checking it, which is extremely useful as navigation.

[Brief description of drawings]

FIG. 1 is a block diagram of a map display device according to an embodiment of the present invention.

FIG. 2 is a diagram and a diagram showing an example of map display in the embodiment of the present invention.

FIG. 3 is a diagram showing an example of a map display in the embodiment of the present invention.

FIG. 4 is a flowchart of a main part in the embodiment of the present invention.

[Explanation of symbols]

 1 Map Storage Means 2 Position Detection Means 3 Control Means 4 Input Means 5 Display Means

Claims (2)

[Claims] 1. A map storage unit for storing map information, a position storage unit for storing coordinate information of a current position, map information read from the map storage unit, and display data is generated by referring to the coordinate information of the position storage unit. Control means, a display means for displaying with display data, and an input means relating to a display position, the control means, when generating the display data, the coordinate information in the approximate center of the screen of the display means. A map display device characterized in that display data is generated correspondingly and the display coordinates of the coordinate information on the screen are moved in response to the operation time of the input means. 2. A map storage means for storing map information, a position detection means for detecting coordinate information of a current position and direction information about a traveling direction, and the map information read out from the map storage means. The display device has a control means for generating display data by referring to the coordinate information and a display means for performing display by the display data, and the control means displays the coordinate information on the screen of the display means in generating the display data. A map display device which moves the display coordinates of the coordinate information on the screen in response to the azimuth information when it does not correspond to substantially the center of the map display device.