JPH06162393A - Method for drawing map in on-vehicle navigator - Google Patents

Abstract

PURPOSE:To provide the method for drawing map in on-vehicle navigator with the improved utility for road guide. CONSTITUTION:A map picture drawing section 12 draws the map picture pointing the north upward basing on the map data related to the present location stored in a CD-ROM 1 on a 1st video RAM 15. By controlling a readout control section 17, one screen of the picture around the vehicle position and pointing the north upward is read out from the 1st video RAM 15. When VICS data including the data for guide are received by a road traffic information receiver 5, a road guide picture drawing section 13 draws the road guidance picture on a 2nd video RAM 16 so that the north is placed at the upper part on the map. A synthesis section 19 synthesizes the road guidance picture the upper part of the left of the map picture read out by the reading control section 17, displaying it on the screen of a CRT display device 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a map drawing method for an in-vehicle navigator, and more particularly to a map drawing method for an in-vehicle navigator for drawing a road guide image and synthesizing the road guide image when a road guide is received from VICS. Regarding

[0002]

2. Description of the Related Art There is a vehicle-mounted navigator which guides a vehicle so that a driver can easily reach a desired destination. In this vehicle-mounted navigator, while traveling, the position and direction of the vehicle are detected, the map data around the vehicle position is read from the CD-ROM, the map image is drawn in the V-RAM, and the current position on the map image is equivalent. Where you want to
The vehicle position mark is overlaid and drawn in a direction corresponding to the direction of travel of the vehicle, and the image of the V-RAM is converted into a video signal while C is displayed.
Output to RT display device and display on screen. As the current position changes as the vehicle moves, for example, the vehicle position mark is fixed at the center of the screen and the map is scrolled so that the map information around the vehicle position can always be seen at a glance.

The map stored in the CD-ROM is managed as a map leaf, which is divided into regions of a longitude width and a latitude width of an appropriate size according to the scale level, with the north as the top, as in a map book. And each leaf is further divided into four data units (see FIG. 16). The map data includes
From (1) background layer for displaying roads, parks, rivers, etc. (2) character / symbol layer for displaying municipalities, road names, symbols, etc. (3) road layer for performing map matching It is configured. The map image is drawn using the background layer and the character / symbol layer. The map data is expressed so that north faces upward on the screen.

In the background layer, the road is represented by line data (vector data), and the road is divided into sections,
Each section includes position coordinates of the starting point and the ending point, a line width code and a color code according to the type of road. Road drawing
While linearly interpolating between the start point and the end point, the process of drawing a straight line of the thickness specified by the line width code and the color specified by the color code is repeated for each section. The line data includes railways as well as roads.

Parks, rivers, etc. are represented by surface data, and include the coordinates of the vertices of the polygonal contour and the color code to fill the inside. When drawing parks, rivers, etc., the polygonal contours are drawn by connecting straight lines of the color specified by the color code while performing linear interpolation between the vertex coordinates, and the inside of the polygonal contour is specified by the color code. It is done by painting with color.

The character data in the character / symbol layer includes the number of characters, character code, vertical / horizontal identification code, display start position coordinate of character, color code, and size code. Characters are drawn in a pattern according to the character code, vertical / horizontal identification code, and size code.
In addition, it is performed by generating a color pattern corresponding to the color code and writing vertically or horizontally from the display start position coordinates. The data of the symbols in the character / symbol layer are the symbol code,
It contains the display start position coordinates of the symbol, the color code, and the size code. The drawing of the symbol is performed by generating a pattern corresponding to the symbol code and the size code and a color pattern corresponding to the color code and horizontally writing from the display start position coordinates. As shown in FIG. 17, the display start position of the character / symbol is defined by the position coordinates of the P _S point in the upper left corner in the case of vertical writing and the Q _S point in the lower left corner in the case of horizontal writing.

The road layer has a structure shown in FIG. The road list RDLT is classified into roads by road type (highway, national road, other roads), the total number of nodes that make up the road, and the node table NDTB of the nodes that make up the road.
It is composed of data such as the position above and the width to the next node. The intersection constituent node list CRLT is the node table NDTB of the other end node of the link (referred to as the intersection constituent node) that is connected to each intersection on the map.
It is a set of positions above. Neighbor node list NNLT
Indicates the number of units shared by other nodes, excluding its own unit, when the node is an adjacent node defined on a unit boundary for a road that spans multiple units and shared by multiple units (see FIG. 19). Number of adjacent nodes (Fig. 19
Regarding the adjacent node RN defined by the unit AU ₁ (AU ₂ ) in (1), the other shared unit is AU ₂ (A
U ₁ ), the number of adjacent nodes is 1, and FIG.
With respect to the adjacent node RN defined by the unit AU ₁₁ in (2), the other shared units are AU ₁₂ , AU ₂₁ , and AU.
_{Since the} number of adjacent nodes is three, the number of adjacent nodes is 3), the drawing leaf number, the unit code to which the adjacent node belongs in the drawing leaf, and the position of the unit on the node table.

The node table NDTB is a list of all the nodes on the map. For each node, coordinate information (longitude, latitude), an intersection identification flag indicating whether or not the node is an intersection, and if the intersection is an intersection constituent node list. Pointer pointing to the position above, if not an intersection, a pointer pointing to the position of the road to which the node belongs on the road list, the adjacent node identification flag whether the node is an adjacent node, if the adjacent node, It is composed of a pointer or the like indicating a position in the adjacent node list NNLT.

When a map image is displayed on the screen, an inexpensive popular type vehicle-mounted navigator is designed to display the map image in a fixed direction so that the north on the map image always faces the top of the screen while driving. A simple north-up display is made. However, when the vehicle travels in a direction different from the north such as south, southeast, southwest, etc., the upward direction of the map image displayed on the screen and the vehicle traveling direction are different. It is inconvenient because it is difficult to associate it with the target object.

Therefore, in the high-class type, a high-speed device capable of rotating and drawing an image in real time is mounted, and in addition to the north-up display mode, the traveling direction of the vehicle on the map image is always linked with the change of the vehicle direction during traveling. A head-up display mode is also possible in which the image is displayed while rotating so that it faces the top of the screen. According to this head-up display mode, since the upward direction of the map image displayed on the screen is the same as the vehicle traveling direction, the road or target on the map can be easily associated with the actual road or target.

By the way, in the vehicle-mounted navigator, if not only the map image around the vehicle position is displayed on the screen, but also the road guide, traffic jam / construction information, traffic regulation information, etc. can be displayed, Is convenient because it makes it possible to travel to a desired place on a more accurate route while comprehensively judging various road information. For this reason, a quasi-microwave beacon, FM from the outside of a vehicle equipped with an in-vehicle navigator
It provides various static information such as location information, road guidance information, etc. by wireless communication such as multiplex broadcasting, and various dynamic information such as traffic jam / construction information, traffic regulation information, etc. VIC that displays information on the screen
S (Vehicle Information & Communication System) is being put to practical use.

[0012] The method of road guidance (destination guidance) in VICS is to use a quasi-microwave from a roadside beacon transmitter arranged along the road to obtain roads according to the shape of the intersection and the destination for each of the main intersections in the forward direction of travel. Name, destination name,
Send information such as required distance. On the vehicle side, the beacon is received by the onboard antenna and the road traffic information receiver (VIC) is received.
The S receiver) receives and demodulates the road guidance data and sends it to the vehicle-mounted navigator. The vehicle-mounted navigator draws the road guidance image based on the road guidance data and combines it with the map image to display it on the screen. The road guide image is 1 / of the screen
It is displayed in a size of about 6 to 1/9.

The shape of an intersection during road guidance is generally represented by surface data, and includes coordinates of each vertex of a polygonal contour and a color code (usually white) to fill the inside.
Intersection shape drawing is performed by linear interpolation between vertex coordinates.
This is performed by drawing a connecting polygonal contour with a straight line of a color designated by the color code and filling the inside of the polygonal contour with the color designated by the color code.

Character data in road guidance generally includes the number of characters, a character code, a vertical / horizontal identification code, a display start position coordinate of the character, a color code, and a size code. Characters are drawn in a pattern according to the character code, vertical / horizontal identification code, and size code.
In addition, it is performed by generating a color pattern corresponding to the color code and writing vertically or horizontally from the display start position coordinates.

[0015]

By the way, unlike the map data, the road guidance data is based on the installation position of the on-road beacon transmitter so that the direction in which the vehicle is traveling along the road is the upward direction. Is expressed. Therefore, when the map image on the screen is displayed in the north-up display mode, the orientation of the road guidance target intersection in the road guidance image matches the orientation of the guidance target intersection on the map image, as shown in FIG. Therefore, it is difficult to associate the road guide with the map image, and it is not possible to quickly determine which direction to proceed at the intersection to reach a desired location on the map image. There is.

In view of the above, an object of the present invention is to provide a map drawing method for an in-vehicle navigator which improves the usability of road guidance.

[0017]

SUMMARY OF THE INVENTION In the present invention, the above object is to provide a map information storing means for storing map data, a means for detecting a current position and a vehicle direction of a vehicle, a current position of the vehicle and a vehicle direction during traveling. Using the map data stored in the map information storage means while detecting, a means for drawing a map image in which the vehicle position mark is superimposed on the map around the current position of the vehicle with the north facing upward, and road guidance from VICS are received. And a means for drawing the road guide image with the north facing upward and synthesizing it with the map image.

[0018]

According to the present invention, when the road guidance is received from the VICS and the road guidance image is drawn and is combined with the map image, the road guidance image is drawn with the north facing upward. As a result, when the map image is displayed in the north-up display mode, the road guide image is also displayed with the north facing upward, so that it is possible to easily associate the road guide with the map image. In order to reach a certain desired place above, it is possible to quickly determine in which direction the intersection should go.

Further, the road guide is received from VICS,
When the road guide image is drawn and combined with the map image, the map image is drawn so that the top is the vehicle traveling direction. As a result, when the map image has been displayed in the north-up display mode until then, when the road guidance image is displayed, the map image is automatically displayed so that the top is the vehicle traveling direction. The guidance and the map image can be easily associated with each other, and it is possible to quickly determine in which direction the intersection should be advanced to reach a desired place on the map image.

The optimum guide route connecting the departure place and the destination is obtained in advance by using the map data stored in the map information storage means, and the map information is detected while the current position and the direction of the vehicle are detected during traveling. The map data stored in the storage means is used to draw a map around the vehicle's current position on which the vehicle position mark is superimposed, and a map image including route guidance information to reach the destination, and the road guidance is received from the VICS. In the map drawing method of the vehicle-mounted navigator, which is configured to draw the road guide image and to combine it with the map image when
When the road guidance is received from the VICS and the road guidance image is drawn, the guidance route data is referred to determine the direction in which the road is to be guided, and the route information is synthesized and drawn in the road guidance image. As a result, by looking at the road guidance image, it is possible to easily and accurately grasp in which direction the traveling road can be advanced to reach the desired destination along the guide route, and it is possible to erroneously deviate from the guide route. It can make things less likely to occur.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall configuration diagram of an in-vehicle navigator embodying a map drawing method according to a first embodiment of the present invention. In the figure, 1 is a CD-RO serving as a map data storage means.
M and 2 are operation panels, which are provided with a map search key, an enlargement / reduction key, a display mode switching key, and the like. 3 is a vehicle position detection unit that detects the vehicle direction and the vehicle position by self-contained navigation, and outputs the vehicle direction data and the vehicle position data. 4 is a quasi-microwave beacon from a roadside beacon transmitter arranged along the road. An in-vehicle antenna that wakes up, 5 is a road traffic information receiver (VICS receiver) that receives and demodulates VICS data from a beacon, and 6 is a CRT display device that inputs a video signal and displays a map of vehicle position marks on the screen,
It is displayed together with road information. The vehicle position detector 3
It is assumed that the vehicle azimuth data θ _V measured clockwise is output with the north as the reference azimuth (= 0 °) (see FIG. 2).

Reference numeral 10 denotes a navigation controller having a microcomputer configuration, which displays a map image around the vehicle position on the screen of the CRT display device 6 together with a vehicle position mark, road guidance and the like. Of these, 11 is a CD-ROM 1
A buffer memory for temporarily storing the map data read from the device, 12 is a map image drawing unit, and includes one map including the current position detected by the vehicle position detection unit during traveling and eight peripheral images surrounding the map. The map data of the
While reading from the ROM 1 to the buffer memory 11,
Of the map data, background layers (parks, rivers, roads, etc.), character / symbol layers (road names, place names, map symbols, etc.)
Accordingly, one map including the current position is set as the center, and a map image integrated with the eight maps around the map is drawn in the first video RAM described later with the north facing upward.

Reference numeral 13 denotes a road guide image drawing unit, which receives and demodulates VICS data including road guide data by the road traffic information receiver 5, and the road guide data (here, an intersection shape composed of plane data). Based on the data and the character data indicating the road name, the destination name, the distance to the road guidance target intersection, etc.), the road guidance image will be described later while referring to the vehicle direction data input from the vehicle position detection unit 3.
It is drawn in the video RAM so that the north direction is upward (in the north-up display mode) or the vehicle traveling direction is upward (in the head-up display mode).

However, since the road guidance data is originally expressed in such a manner that both the intersection shape data and the character data are drawn in the second video RAM so that the vehicle traveling direction is upward, the road guidance image is drawn. In the head-up display mode, the unit 13 draws the road guidance image using the received intersection shape data and character data as it is, but in the north-up display mode, as shown in FIG. Is the second video RAM when the vehicle traveling direction is drawn upward in the second video RAM.
With the position corresponding to the center of the origin as the origin C, the intersection shape data and the coordinate data in the character data are rotationally converted around the origin C by the current direction θ _{V of the} vehicle in the counterclockwise direction, and the intersection shape data after the conversion is obtained. Second video R using character data
A road guide image is drawn on the AM (see FIG. 3 (2)).

Numeral 14 is an intersection passage judging section which internally registers the beacon position coordinate data in the VICS data at the time of receiving the beacon including the data for road guidance, and the vehicle position data detected by the vehicle position detecting section 3. Of the map data stored in the buffer memory 11 based on the vehicle direction data, particularly with reference to the road layer (see FIG. 18), the road guidance target existing ahead of the traveling road and the vehicle traveling direction at the time of beacon reception. The intersection is specified and internally registered, and when the vehicle comes to a position ahead of the road guidance target intersection from the beacon position, it is determined that the vehicle has passed the road guidance target intersection.

Here, since the method of specifying the road on which the vehicle is traveling and the intersection to be guided by the road is generally carried out on the main roads such as highways and national roads, the vehicle in the road list RDLT of the road layer is selected. It is located at the closest point in front of the vehicle in the traveling direction at the intersection of the road where the position is on, the road that is running is identified, and the road intersects with the road whose type data is highway or national road. The specified intersection is specified as the target intersection for road guidance, or the road guidance data contains "○○ m ahead" or "○○○
When the data indicating the distance from the beacon position to the road guidance target intersection is included as in “m”, the road that is running is a road that is distant by a distance corresponding to the forward direction of the vehicle. It is specified as a guidance target intersection. Further, it is also possible to specify the road on which the vehicle is running and the intersection targeted for road guidance by using the VICS link information included in the VICS data. Further, a special flag indicating a road guidance target intersection is set for a node corresponding to the road guidance target intersection in the road list RDLT of the road layer or the node table NDTB, and by referring to the flag, the road guidance target intersection May be specified.

It should be noted that the intersection passage determination unit 14 does not specify the road on which the vehicle is running or the road guidance target intersection, but may determine that the vehicle has passed the road guidance target intersection after a certain time has elapsed since the beacon was received. Good.

Reference numeral 15 denotes a first video RAM having a storage capacity for 9 screens of the CRT display device 6 and storing a map image drawn by the map image drawing unit 12, and 16 a C
A second video RAM 17 having a storage capacity of about 1/9 screen of the RT display device 6 and storing the road guide image drawn by the road guide image drawing unit 13 is a read control unit and draws a map image. In response to the read control of the unit 12, from the first video RAM 15, centering on the vehicle position,
A one-screen map image with the top facing north (in the north-up display mode) or a one-screen map image with the top facing the vehicle traveling direction (in the head-up display mode) is read.

Reference numeral 18 denotes a vehicle position mark generator, which has a predetermined size and an arrow pointing upward (in the head-up display mode).
Alternatively, the arrow generates a vehicle position mark in the vehicle traveling direction (in the north-up display mode). Reference numeral 19 denotes a synthesizing unit for synthesizing and outputting a vehicle position mark at the center of the map image read by the read control unit 17 (when the road guide is not displayed), or a map read by the read control unit 17. The vehicle position mark is combined at the center of the image, and the road guide image is combined and output at the upper left (when the road guide image is displayed). The composition of the road guide image is
It is performed after the beacon is received until the vehicle passes the road guidance target intersection. Reference numeral 20 denotes a video conversion unit that converts the image combined by the combining unit into a video signal and outputs the video signal to the CRT display device 6.

FIGS. 4 and 5 are flow charts showing the navigation processing of the navigation controller 10, and FIGS. 6 to 8 are explanatory diagrams showing examples of screen display on the CRT display device 6, which will be described below with reference to these figures.

When the power supply of the set is turned on, the vehicle position detection unit 3 thereafter detects the vehicle position and the vehicle direction, and outputs the vehicle position data and the vehicle direction data. Further, when the road traffic information receiver (VICS receiver) 5 receives a beacon from the road beacon transmitter, it demodulates and outputs VICS data.

After the power is turned on, the navigation controller 10 first sets the north-up display mode as desired (step 101 in FIG. 4). Next, the map image drawing unit 12 inputs the vehicle position data and the vehicle azimuth data from the vehicle position detecting unit 3 and refers to the map leaf management information in the map data to refer to the first video RAM 15 and the current position is the center one. It is checked whether the map images included in the map No. 1 and the eight maps surrounding the map have been drawn (step 102). Since no image is drawn in the first video RAM 15 at first, it is determined as NO. In this case, one map including the current location and the data of the map around the map are all read from the CD-ROM 1 and stored in the buffer memory 11 (step 1
03). Then, using the background layer and the character / symbol layer around the current location of the read map data, a map image in which one central map including the current location and eight maps surrounding the current map are integrated, One video RAM 15 is drawn with the north facing upward (step 104).

Next, since it is currently in the north-up display mode, the map image drawing unit 12 outputs the read center position data corresponding to the vehicle position in the map image drawn in the first video RAM 15 and the read direction data indicating the upper north. It is given to the read control unit 17 to perform read control, and the read control unit 17 is made to read one screen from the first video RAM 15 with the vehicle position at the center and the upper direction facing north (steps 105 and 106). . In addition, the vehicle position mark generation unit 18 generates a vehicle position mark having a predetermined size and oriented in the vehicle azimuth direction based on the vehicle azimuth data input from the vehicle position detection unit 3 (step 107).

Next, the navigation controller 10
Checks whether the road guide image is being displayed (step 10
8), because it is NO, the road traffic information receiver 5 continues to VI
Check if CS data is received (step 10
9), if NO, the synthesizing unit 19 reads the read control unit 17
The vehicle position mark generated by the vehicle position mark generation unit 18 is combined with the center of the map image for one screen output from (the road guide image is not combined). The image combined by the combining unit 19 is converted into a predetermined video signal by the video converting unit 20 and output to the CRT display device 6. As a result, a map image including a vehicle position mark in the center is displayed on the screen with the top facing north (step 110, FIG. 6).
(See (1)).

After step 110, the navigation controller 10 checks whether or not the display mode switching key has been pressed on the operation unit 2 (step 111), and if NO, returns to step 102 and repeats the same processing as described above. However, when the vehicle is traveling, the vehicle position and the vehicle direction change, but if the vehicle position is not currently within the range of one map in the center drawn in the first video RAM 15, After the processing of steps 103 and 104 is not performed, the process proceeds to step 105 and thereafter, and one screen is read from the first video RAM 15 with the vehicle position as the center and the north as the upward direction, and is combined with the vehicle position mark in the vehicle azimuth direction. , Are displayed on the screen (steps 106 to 110).

If the vehicle position has been drawn in the first video RAM 15 by the check in step 102,
If it exceeds the range of one map in the center, the map image drawing unit 12 refers to the map leaf management information and refers to the CD-ROM 1
Read all the necessary map data from the buffer memory 1
After storing in 1 (step 103), a map image in which one central map including the current location and eight maps surrounding the map are integrated is drawn in the first video RAM 15 with the north facing upward. Repair (step 104).

In this manner, as the vehicle travels, the map image on the screen scrolls while the vehicle position is fixed at the center, so that the driver can always see the map around the vehicle position.

Thereafter, when the vehicle passes directly under the road beam transmitter and VICS data is received by the road traffic information receiver 5 while traveling in the north-up display mode, the navigation controller 10 performs YE in step 109.
Judge as S. At this time, moving to the flow of FIG. 5, first,
The navigation controller 10 checks whether the VICS data includes road guidance data (step 201), and if YES, the intersection passage determination unit 14 later determines whether the vehicle has passed the road guidance target intersection. In preparation for, the beacon position coordinate data in the VICS data is internally registered (step 202), and from the VICS data, the current position data of the vehicle, the vehicle direction data, the road layer in the map data stored in the buffer memory 11, and the like. A road on which the vehicle is running and a road guidance target intersection are specified and internally registered (step 203).

Next, since the road guide image drawing unit 13 is currently in the north-up display mode, the road guide image drawing unit 13 uses the road guide data (intersection shape data and character data) for the second
A road guide image is drawn in the video RAM 16 so that the upper side faces north (steps 204 and 205). On this occasion,
As shown in FIG. 3 (1), the road guide image is temporarily displayed on the second video RA.
The origin shape C is the position corresponding to the center of the second video RAM 16 when the vehicle traveling direction is drawn upward in M16, and the intersection shape data and the coordinate data in the character data are
The vehicle is rotated in the counterclockwise direction around the origin by the current direction θ _V of the vehicle, and a road guidance image is drawn in the second video RAM using the converted intersection shape data and character data (FIG. 3).
(See (2)).

After that, the synthesizing unit 19 reads the read control unit 17.
The vehicle position mark generated by the vehicle position mark generating unit 18 is combined with the center of the map image for one screen output from, and the road guide image drawn in the second video RAM 16 is combined at the upper left. The image combined by the combining unit 19 is converted into a predetermined video signal by the video converting unit 20 and output to the CRT display device 6. As a result, a map image including a vehicle position mark is displayed in the center of the screen with the top facing north, and a road guide image is displayed in the upper left of the screen (step 206, see FIG. 6 (2)).

After step 206, the navigation controller 10 checks whether the display mode switching key has been pressed on the operation unit 2 (step 111 in FIG. 4).
If NO, the process returns to step 102 and the same processing as described above is repeated. In the subsequent processing of step 108, the navigation controller 10 determines YES because the road guidance image is currently being displayed on the screen, but in this case, the intersection passage determination unit 14 determines that the vehicle position input from the vehicle position detection unit 3 has occurred. The vehicle passed through the road guidance target intersection from the data, the beacon position coordinate data internally registered previously, the data identifying the traveling road and the data identifying the road guidance target intersection, the road layer stored in the buffer memory 11, and the like. (Step 112), and if NO,
An image obtained by combining the vehicle position mark and the road guide image on the map image is displayed on the screen by the combining unit 19 (step 206 in FIG. 5).

After that, by repeating the same processing, when the map image is displayed in the north-up display mode, the road guide image is also displayed with the north facing upward.
Correspondence between the road guide and the map image can be easily performed, and it is possible to quickly determine in which direction the intersection should be advanced to reach a desired place on the map image.

When the driver looks at the road guidance image and the map image to check the route at the road guidance target intersection and drives the vehicle to pass through the road guidance target intersection in the desired direction, the intersection passage determination unit 14 It is determined to be YES in step 112 of 4. At this time, the process proceeds to step 110, and the combining unit 1
Reference numeral 9 synthesizes only the vehicle position mark generated by the vehicle position mark generation unit 18 at the center of the map image for one screen output from the read control unit 17 (does not synthesize the road guide image). The image combined by the combining unit 19 is converted into the image conversion unit 20.
Is converted into a predetermined video signal and output to the CRT display device 6. As a result, the road guide image disappears from the screen, and the screen returns to the normal map screen (see FIG. 7 (1)).

In the same manner, every time the vehicle passes directly under the road beacon transmitter, the road guide image is combined with the upper left corner of the screen, and if it passes through the road guide target intersection, the original map image is restored. Repeat the operation.

The above is the operation in the head-up display mode, but unlike this, when the driver is traveling in the head-up display mode and the road guidance image is not displayed, the operation unit 2 is operated. When the display mode switching key is pressed, the navigation controller 10 switches the display mode to the head-up display mode (step 111).
YES, 113, 114).

In the head-up display mode, the map image drawing unit 12 reads the read center position data corresponding to the vehicle position in the map image drawn in the first video RAM 15,
Read-out direction data indicating the vehicle azimuth direction is given to the read-out control unit 17 to perform read-out control, and the read-out control unit 17 causes the first video RAM 15 to center the vehicle position and the upper direction as the vehicle azimuth direction. The screen portion is read (steps 105 and 115). Further, the vehicle position mark generating unit 18 generates a vehicle position mark having a predetermined size and facing upward based on the vehicle direction data input from the vehicle position detecting unit 3 (step 116). Therefore, on the screen, a map image with the vehicle traveling direction at the top is displayed together with the vehicle position mark, the map scrolls according to the change of the vehicle position, and the map changes according to the change of the vehicle direction. It will rotate (see FIG. 7 (2)).

In this state, when the vehicle passes directly under the road beam transmitter and the VICS data including the road guidance data is received by the road traffic information receiver 5, the navigation controller 10 proceeds to step 109, as shown in FIG. It is determined to be YES in step 201. At this time, as described above,
First, as a preparation for the intersection passage determination unit 14 to determine whether the vehicle has passed the road guidance target intersection later, the VIC
The beacon position coordinate data in the S data is internally registered (step 202), and the VICS data, the current vehicle position data, the vehicle heading data, and the buffer memory 11 are also registered.
From the road layer and the like in the map data stored in, the running road and the road guidance target intersection are specified and internally registered (step 203).

Next, since the road guide image drawing unit 13 is currently in the head-up display mode, the road guide image drawing unit 13 uses the road guide data (intersection shape data and character data) to generate the second data.
A road guide image is drawn in the video RAM 16 so that the upper direction is the traveling direction of the vehicle (steps 204 and 205). In this case, since the road guidance data is defined from the beginning so that the vehicle traveling direction is upward, the road guidance image may be drawn using the data as it is.

Thereafter, the synthesizing unit 19 causes the read control unit 17 to operate.
The vehicle position mark generated by the vehicle position mark generating unit 18 is combined with the center of the map image for one screen output from, and the road guide image drawn in the second video RAM 16 is combined at the upper left. The image combined by the combining unit 19 is converted into a predetermined video signal by the video converting unit 20 and output to the CRT display device 6. As a result, a map image including a vehicle position mark is displayed in the center of the screen with the top facing north, and a road guide image is displayed in the upper left of the screen (step 206, see FIG. 8 (1)).

After step 206, the navigation controller 10 checks whether the display mode switching key has been pressed on the operation unit 2 (step 111 in FIG. 4),
If NO, the process returns to step 102 and the same processing as described above is repeated. The navigation controller 10 determines YES in the subsequent processing of step 108, but in this case, the intersection passage determination unit 14 determines the vehicle position data input from the vehicle position detection unit 3, the beacon position coordinate data previously internally registered, and the traveling position. Data for specifying an inside road and data for specifying a road guidance target intersection, buffer memory 11
It is checked whether the vehicle has passed the road guidance target intersection from the road layer or the like stored in (step 112), and if NO, the synthesizing section 19 is executed and the one-screen map image output from the read control section 17 is output. The vehicle position mark and the road guide image are combined and displayed on the screen (step 2 in FIG. 5).
06).

After that, by repeating the same processing, when the map image is displayed in the head-up display mode, the road guidance image is also displayed with the vehicle traveling direction facing upward. Correlation can be done easily, and to reach a desired place on the map image,
It is possible to quickly determine in which direction to proceed at the intersection.

When the driver drives the vehicle while checking the route at the road guidance target intersection by looking at the road guidance image and the map image and passing the road guidance target intersection in the desired direction, the intersection passage determination unit 14 It is determined to be YES in step 112 of 4. At this time, the process proceeds to step 110, and the combining unit 1
Reference numeral 9 synthesizes the vehicle position mark generated by the vehicle position mark generation unit 18 at the center of the map image for one screen output from the read control unit 17 (the road guidance image is not synthesized). The image combined by the combining unit 19 is converted into the image conversion unit 20.
Is converted into a predetermined video signal and output to the CRT display device 6. As a result, the road guide image disappears from the screen, and the screen returns to the normal map screen (see FIG. 8 (2)).

According to this embodiment, when the beacon is received in the state where the map image is displayed in the head-up display mode, the road guide image is drawn so that the north is facing upward, and the map image is combined with the map image. Therefore, it is possible to easily associate the road guide with the map image, and quickly determine which direction to proceed at the intersection to reach a certain desired place on the map image. can do.

In the first embodiment described above, the in-vehicle navigator capable of switching the display mode between the north-up display mode and the head-up display mode is targeted, but the same applies to the in-vehicle navigator capable of only the north-up display mode. Can be applied.

When a beacon including road guidance data is received while traveling in the north-up display mode,
The road guide image is drawn with the north facing upward, and the map image is combined and displayed on the screen. However, unlike this, the steps 108, 109 and 112 of FIG. 4 and the flow of FIG. V to include the data for road guidance
When the ICS data is received (NO in step 301 of FIG. 9, YES in 302, 303), first, the navigation controller 10 temporarily sets the heads-up display mode automatically (steps 304, 305) and displays the road guide image. The second video RAM 16 so that is in the vehicle traveling direction.
(Steps 306 to 308).

Then, the map image drawing unit 12 performs read control to the read control unit 17 in the head-up display mode until the vehicle passes the road guidance target intersection, and the vehicle position mark generation unit 18 also operates in the head-up display mode. A position mark is generated (upward vehicle position mark is generated),
The synthesizing unit 19 synthesizes the vehicle position mark in the center of the map image whose vehicle traveling direction is the upper direction output from the reading control unit 17, and synthesizes the road guide image in the upper left and displays it on the screen (step 309, step 111 in FIG. 4). , 102-105, 1
15, 116, steps 301, 310, 30 of FIG.
9, FIG. 8 (1)).

As described above, when the beacon is received in the state that the map image is displayed in the north-up display mode, the road guide image and the map image are drawn and combined in the head-up display mode to obtain the road guide. It is possible to easily associate the map images with each other, and it is possible to quickly determine in which direction the intersection should be advanced in order to reach a desired place on the map image.

After the vehicle passes through the road guidance target intersection, the navigation controller 10 returns to the north-up display mode (YE at step 310 in FIG. 9).
(S311, 312), the map image drawing unit 12 performs read control to the read control unit 17 in the north-up display mode, and the vehicle position mark generation unit 18 also generates the vehicle position mark in the north-up display mode (vehicle direction). The vehicle position mark in the direction direction is generated), and the synthesizing unit 19 synthesizes the vehicle position mark at the center of the map image output from the read control unit 17 with the vehicle traveling direction above and displays it on the screen (FIG. Steps 110, 111, 102-10
7, steps 301 and 302 in FIG. 9, step 1 in FIG.
10).

FIG. 10 is a block diagram of the essential parts of an in-vehicle navigator embodying the map drawing method according to the second embodiment of the present invention. The same components as those in FIG. 1 are designated by the same reference numerals. The second embodiment shows a case where a route is guided from a starting point to a destination.

When the starting point data and the destination point data are input, reference numeral 21 refers to the map leaf management information, and the map data of a range including a rectangular area whose diagonal line is a straight line connecting the starting point and the destination point from the CD-ROM 1. While reading out to the buffer memory 11, by using the road layer of the read map data, the shortest optimum route connecting the starting point to the destination is searched by the Dijkstra method, horizontal search method, etc., and the searched route is constructed. An optimum route searching unit that stores the selected node sequence as guide route data in a guide route storage unit, which will be described later, and 22 is a guide route storage unit that stores the guide route data.

Reference numeral 23 denotes a route determining unit for obtaining a route at the road guidance target intersection, which is specified by the intersection passage determining unit 14 on the guide route with reference to the guide route data stored in the guide route recording unit 22. The route is obtained from the positional relationship between the node corresponding to the road guidance target intersection and the preceding and following nodes (see FIG. 11). Reference numeral 24 is a route character generation unit for outputting character data (“straight ahead”, “left turn”, “right turn”, etc.) representing the route obtained by the route determination unit 23.

The map image drawing section 12A uses the first video RA.
When drawing an image on M15, after drawing a map image based on the map data, the guide route data stored in the guide route storage unit 22 is normally used by using the data in the drawing area of the map image. The emphasized guidance route that is thickly emphasized in a color that can be distinguished from the road is drawn in a superimposed manner. On the other hand, the road guidance image drawing unit 13A draws a road guidance image with the vehicle traveling direction facing upward in the second video RAM 16 using the road guidance data as it is, and then based on the character data input from the route character generation unit 24. , The character indicating the route is drawn on the upper right of the road guide image. The other components are configured similarly to FIG.

12 and 13 are flow charts showing the operation of the navigation controller 10A according to the second embodiment, FIG.
Reference numeral 4 is an explanatory view of screen display examples, which will be described below with reference to these drawings. It is assumed here that the display mode of the navigation controller 10A is fixed to the head-up display mode in advance.

When the starting point and the destination are input, the optimum route searching section 21 obtains from the CD-ROM 1 one or a plurality of map data in a range including a rectangular area having a straight line connecting the starting point and the destination as a diagonal line. Of the map data read out to the buffer memory 11, the road layer in particular (see FIG. 18)
Is used to search for the optimum route connecting the starting point to the destination by the Dijkstra method, horizontal search method, etc. (steps 401 and 402 in FIG. 12). Then, the node sequence forming the searched optimum route is stored in the guide route storage unit 22 as guide route data (step 403).

Next, the map image drawing section 12A inputs the vehicle position data and the vehicle direction data from the vehicle position detecting section 3 and refers to the map leaf management information in the map data to refer to the first video RAM 15 so that the current position is already in the center. It is checked whether or not the map images included in one of the maps and integrated with the eight maps surrounding the map have been drawn (step 404). At first, nothing is drawn in the first video RAM 15, so N
If it is judged as O, in this case, one map including the current location and the data of the map around the map are all read from the CD-ROM 1 and stored in the buffer memory 11 (step 40).
5). Then, using the background layer and the character / symbol layer around the current location of the read map data, a map image in which one central map including the current location and eight maps surrounding the current map are integrated, One video RAM 15 is drawn with the north facing upward (step 406). Next, of the guide route data stored in the guide route storage unit 22, using the data in the drawing area of the map image, the emphasized guide route that is thickly emphasized in a color distinguishable from a normal road is displayed. Drawing is overlaid (step 407).

Next, the map image drawing unit 12A causes the read control unit 17 to read the read center position data corresponding to the vehicle position in the map image drawn in the first video RAM 15 and the read direction data indicating the upper direction of the vehicle. Then, the read control is performed and the read control unit 17 is caused to read one screen from the first video RAM 15 with the vehicle position as the center and the upper direction as the vehicle traveling direction (step 40).
8). Further, the vehicle position mark generation unit 18 generates an upward vehicle position mark having a predetermined size (step 4).
09).

Next, the navigation controller 10A
Checks whether the road guide image is being displayed (step 41
0), NO, so the road traffic information receiver 5 will continue to VI
Check if CS data is received (step 41
1) If NO, the synthesizing unit 19 reads the read control unit 17
The vehicle position mark generated by the vehicle position mark generation unit 18 is combined with the center of the map image for one screen output from (the road guide image is not combined). The image combined by the combining unit 19 is converted into a predetermined video signal by the video converting unit 20 and output to the CRT display device 6. As a result, a map image including the vehicle position mark in the center is displayed on the screen along with the emphasized guidance route in the vehicle traveling direction upward (step 412, see FIG. 14 (1)).

After step 412, the navigation controller 10A returns to step 404 and repeats the same processing as described above. However, when the vehicle is running,
Although the vehicle position and the vehicle azimuth change, if the vehicle position does not exceed the range of the central map currently drawn in the first video RAM 15, steps 405 to 40
The processing of step 7 is not performed, and the process proceeds to step 408, where the first video RA
One screen is read from M15 with the vehicle position as the center and the vehicle traveling direction is upward, and after being combined with the upward-looking vehicle position mark, the screen is displayed (steps 409 to 4).
12).

If it is checked in step 404 that the vehicle position has been rendered in the first video RAM 15 until then,
If it exceeds the range of one central map, the map image drawing unit 12A refers to the map leaf management information and
After all the necessary map data from 1 is read and stored in the buffer memory 11 (step 405), a map image in which one central map including the current location and eight maps surrounding the map are integrated is displayed. One video RAM 15 is redrawn with the north facing upward (step 406). Then, in the guide route data stored in the guide route storage unit 22,
Using the data contained in the drawing area of the map image, the emphasized guidance route, which is thickly emphasized in a color distinguishable from a normal road, is drawn in a superimposed manner (step 407).

In this way, according to the change of the vehicle position,
While the vehicle position is fixed at the center, the map image on the screen scrolls and rotates so that the vehicle traveling direction is upward according to the change in the vehicle direction, so that the driver can always see the map around the vehicle position.

After that, when the vehicle passes directly under the road beam transmitter during traveling and the VICS data is received by the road traffic information receiver 5, the navigation controller 1
0A determines YES in step 411. At this time, moving to the flow of FIG. 13, first, it is checked whether or not the VICS data includes road guidance data (step 5
01), if YES, the intersection passing determination unit 14 internally registers the beacon position coordinate data in the VICS data as a preparation for determining whether the vehicle has passed the road guidance target intersection later (step 502). , The V
ICS data, current vehicle data, vehicle direction data,
From the road layer and the like in the map data stored in the buffer memory 11, the running road and the road guidance target intersection are specified and internally registered (step 503).

Then, the route determination unit 23 refers to the guide route data stored in the guide route storage unit 22, and refers to the guide route data, the node corresponding to the road guidance target intersection specified by the intersection passage determination unit 14 on the guide route and the front and rear. (Step 504, refer to FIG. 11), the route character generation unit 24 character data representing the route determined by the route determination unit 23 (“straight ahead”, “left turn”, “right turn”, etc.). Is output to the road guide image drawing unit 13A (step 505).

On the other hand, the road guide image drawing unit 13A draws the road guide image with the vehicle traveling direction facing upward in the second video RAM 16 by using the road guide data as it is (step 506), and then the route character generation unit 24. Based on the character data input from, the character indicating the route is drawn on the upper right of the road guide image drawn in the second video RAM 16 (step 507).

After that, the synthesizing unit 19 reads the read control unit 17.
The vehicle position mark generated by the vehicle position mark generating unit 18 is combined with the center of the map image for one screen output from, and the road guide image drawn in the second video RAM 16 is combined at the upper left. The image combined by the combining unit 19 is converted into a predetermined video signal by the video converting unit 20 and output to the CRT display device 6. As a result, on the screen, a map image including a vehicle position mark is displayed in the center with the top facing north, and a road guide image is displayed in the upper left of the screen together with characters indicating the route (step 508, FIG. 14).
(See (2)).

After step 508, the navigation controller 10A returns to step 404 in FIG. 12 and repeats the same processing as described above. After this, step 410
Although the navigation controller 10A determines YES in the processing of step 1, in this case, the intersection passage determination unit 14 determines the vehicle position data input from the vehicle position detection unit 3, the beacon position coordinate data previously internally registered, and the traveling road. It is checked whether the vehicle has passed the road guidance target intersection from the data to be specified, the data specifying the road guidance target intersection, the road layer stored in the buffer memory 11 and the like (step 413). If NO, the process proceeds to step 508. .

After that, by repeating the same processing, when the map image is displayed in the head-up display mode, the road guidance image is also displayed with the vehicle traveling direction facing upward, and the route guidance image is displayed to reach the destination. Since the route information is also shown, the driver can easily and accurately determine in which direction the intersection should go to reach the destination.

When the driver drives the vehicle while checking the route at the road guidance target intersection by looking at the road guidance image and the map image, and passes through the road guidance target intersection according to the route information, the intersection passage determination unit 14 Determines YES in step 413. At this time, the process proceeds to step 412, and the combining unit 1
Reference numeral 9 synthesizes the vehicle position mark generated by the vehicle position mark generation unit 18 at the center of the map image for one screen output from the read control unit 17 (the road guidance image is not synthesized). The image combined by the combining unit 19 is converted into the image conversion unit 20.
Is converted into a predetermined video signal and output to the CRT display device 6. As a result, the road guide image disappears from the screen and the normal map screen is restored.

Similarly, each time the vehicle passes directly under the road beacon transmitter, the road guide image including the route information is synthesized on the upper left of the screen. If the vehicle passes the road guide target intersection, the original map is displayed. The operation of returning to the image (including the emphasis guidance route) is repeated until the destination is reached.

According to the second embodiment, when the beacon is received during the route guidance and the road guidance image is displayed, the information indicating the route at the road guidance target intersection is also displayed. It is possible to drive along the guide route easily and accurately. In the second embodiment described above,
Although the route to be taken at the road guidance target intersection is displayed by characters, it may be displayed by an arrow as shown in FIG. Also, when guiding the route in the north-up display mode, when the road guidance image is displayed, the map image remains in the north-up display mode, and the road guidance image with the north facing upward (route information at the road guidance target intersection). May be drawn, or the top of the road guide image may be displayed as the vehicle traveling direction and the map image may be temporarily displayed in a head-up manner.

In each of the above-described embodiments, the vehicle position and the vehicle direction are detected by the self-contained navigation.
It is also possible to use a satellite orbiting an earth-orbiting satellite to perform satellite navigation in which measurement is performed based on the principle of triangulation.

[0081]

As described above, according to the present invention, when the road guidance is received from VICS and the road guidance image is combined with the map image and drawn, the road guidance image is drawn with the north facing upward. Since it is configured, when the map image is displayed in the north-up display mode, the road guide image is also displayed with the north facing upward, so it is possible to easily associate the road guide with the map image. In order to reach a desired place on the map image, it is possible to quickly determine in which direction the intersection should be advanced.

In addition, the road guide is received from VICS,
When the road guide image is combined with the map image and drawn, the map image is drawn so that the upper direction is the traveling direction of the vehicle. Therefore, when the map image has been displayed in the north-up display mode until then. When the road guidance image is displayed, the map image is automatically displayed so that the top is the vehicle traveling direction, so that the road guidance and the map image can be easily associated with each other. It is possible to quickly determine in which direction to proceed at the intersection in order to reach a certain desired location.

Further, in advance, by using the map data stored in the map information storage means, an optimum guide route connecting the departure place and the destination is obtained, and while the vehicle is traveling, the current position of the vehicle and the vehicle direction are detected. Using the map data stored in the map information storage means, a map around the current position of the vehicle on which the vehicle position mark is superimposed and a map image including route guidance information for traveling to the destination are drawn, and the VICS guides the road. In the map drawing method of the vehicle-mounted navigator, the road guide image is drawn when the
When the road guidance is received from the CS and the road guidance image is drawn, the guidance route data is referred to determine the direction in which to travel on the guidance road, and the route information is synthesized and drawn in the road guidance image. Because of the configuration, it is possible to easily and accurately grasp the direction of the traveling road to reach the desired destination along the guide route by looking at the road guidance image.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an in-vehicle navigator embodying a map drawing method according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing how to measure a vehicle direction.

FIG. 3 is an explanatory diagram of a method of drawing a road guide image.

FIG. 4 is a first flowchart showing the operation of the navigation controller according to the first embodiment.

FIG. 5 is a second flowchart showing the operation of the navigation controller according to the first embodiment.

FIG. 6 is an explanatory diagram showing a screen display example.

FIG. 7 is an explanatory diagram showing a screen display example.

FIG. 8 is an explanatory diagram showing a screen display example.

FIG. 9 is a flowchart according to a modification of the first embodiment.

FIG. 10 is an overall configuration diagram of an in-vehicle navigator embodying a map drawing method according to a second embodiment of the present invention.

FIG. 11 is an explanatory diagram of an operation of a route determining unit.

FIG. 12 is a first flowchart showing the operation of the navigation controller according to the second embodiment.

FIG. 13 is a second flowchart showing the operation of the navigation controller in the second example.

FIG. 14 is an explanatory diagram illustrating a screen display example.

FIG. 15 is an explanatory diagram showing a modified example of the second embodiment.

FIG. 16 is an explanatory diagram of how to hold map data on a CD-ROM.

FIG. 17 is an explanatory diagram of a display start position of character data.

FIG. 18 is an explanatory diagram of a road layer.

FIG. 19 is an explanatory diagram of an adjacent node.

FIG. 20 is an explanatory diagram showing a problem of conventional road guidance.

[Explanation of symbols]

 1 CD-ROM 2 Operation panel 3 Vehicle position detection unit 4 Vehicle-mounted antenna 5 Road traffic information receiver 6 CRT display device 10, 10A Navigation controller 12, 12A Map image drawing unit 13, 13A Road guide image drawing unit 15 First video RAM 16 Second Video RAM 17 Read Control Section 19 Compositing Section

Claims (3)

[Claims] 1. A map image in which a vehicle position mark is superimposed on a map around the current position of a vehicle by using map data stored in a map information storage means while detecting the current position and vehicle direction of the vehicle while traveling In the map drawing method of the vehicle-mounted navigator, in which the road guidance image is drawn upward, and when the road guidance is received from the VICS, the road guidance image is drawn upward and is combined with the map image. A map drawing method for an in-vehicle navigator characterized by being drawn in this way. 2. A map image in which a vehicle position mark is superimposed on a map around the current position of the vehicle by using the map data stored in the map information storage means while traveling while detecting the current position of the vehicle and the vehicle direction. When the road guidance is received from VICS, when the road guidance is received from VICS, when the road guidance image is drawn and the road guidance image is combined with the map image in the map drawing method of the vehicle-mounted navigator. Map image,
A map drawing method for an in-vehicle navigator is characterized in that the drawing is performed so that the upper direction is the traveling direction of the vehicle. 3. The map data stored in the map information storage means in advance is used to find an optimum guidance route connecting the departure place and the destination, and while the vehicle is traveling, the current position and the vehicle direction of the vehicle are detected. Using the map data stored in the map information storage means, a map around the current position of the vehicle on which the vehicle position mark is superimposed and a map image including route guidance information for traveling to the destination are drawn, and the VICS guides the road. In the map drawing method of the vehicle-mounted navigator that draws the road guidance image and synthesizes it with the map image when is received, refer to the guide route data when receiving the road guidance from VICS and drawing the road guidance image. Then, the direction to go on the road to be guided is obtained, and the route information is synthesized and drawn in the road guidance image. Method.