JPH052365A - On-vehicle navigator - Google Patents

Abstract

PURPOSE:To provide the on-vehicle navigator which can reduce the burden on an image process. CONSTITUTION:Before departure, map data stored on a CD-ROM 1 are referred to and a search part 15 finds the best guidance route connecting a starting point to a destination and road data on the surroundings of intersections on the guidance course and stores them in a guidance course memory 16. During traveling, an image of the guidance course at the surroundings of a vehicle and roads nearby the intersection on the guidance course is displayed on a CRT display device 4 under the control of a map drawing control part 13 according to the vehicle position data and the data stored in the guidance course memory.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-vehicle navigator,
In particular, it relates to an in-vehicle navigator that provides route guidance along an optimal guide route from a starting point to a destination.

[0002]

2. Description of the Related Art There is a vehicle-mounted navigator that guides a vehicle so that a driver can easily reach a desired destination. In this in-vehicle navigator, the position of the vehicle is 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 vehicle position mark is superimposed on a predetermined position on the map image. Draw and
The V-RAM image is output to the CRT display device while being converted into a video signal and displayed on the screen. As the current position changes due to the movement of the vehicle, 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 divided into regions of appropriate longitude and latitude according to the scale level, and pictures of roads, buildings, rivers, etc. are displayed on the screen. The data for doing so is stored in the background layer, and the road data for map matching is stored in the road layer. In the road data, the road is represented by a set of vertices (nodes) represented by the coordinates of longitude and latitude. A part that connects two or more nodes is called a link. The road data included in each map is the road link data RL as shown in FIG.
It is composed of DT, node data NDDT, and intersection data CRDT, of which road link data RLDT
Indicates the attribute information of the road link, and is composed of data such as the total number of nodes on the link, the number on the node data NDDT of each node forming the link, the road name, and the road type. Further, the intersection data CRDT is a set of numbers on the node data NDDT of a node (referred to as an intersection composing node) that is the closest to the intersection on a link connecting to the intersection, and the node data NDDT is the map. It is a list of all the nodes above, coordinate information (longitude, latitude) for each node, an intersection identification flag indicating whether the node is an intersection, if it is an intersection, it points to the intersection data, and if it is not an intersection, the node is It is composed of a pointer or the like pointing to the road link to which it belongs.

By the way, some vehicle-mounted navigators have a route guidance function that guides a route from an origin to a destination along an optimum route. In such route guidance,
If the driver sets the starting point and the destination before traveling, the CD-
A simulation calculation is performed by referring to the map data (road layer) in the ROM, for example, an optimum guide route connecting the departure place and the destination with the shortest distance is obtained, and the node sequence forming the guide route and the head departure place The guide route data including the data and the destination data at the end is stored in the guide route memory.

Then, while traveling, a map image of roads, buildings, rivers, etc. around the vehicle position is displayed on the entire screen based on the map data (background layer) around the vehicle position read from the CD-ROM, and at the same time, the guide route. Find out which guide route is in the display area of the screen from the node row in the memory and display the guide route in a different color from other roads to see which road the driver should drive. I am trying.

[0006]

However, the map image of roads, buildings, rivers, etc. on the screen needs to be changed from moment to moment as the position of the vehicle changes during traveling, which imposes a heavy load on image processing. Therefore, the map on the screen is displayed in a head-up manner so that the vehicle traveling direction is always facing upward, or the traveling direction at the intersection in front of the vehicle traveling direction on the guide route is calculated and the intersection guidance is displayed on a part of the screen. There is a problem that it is difficult to display images in real time.

In view of the above, an object of the present invention is to provide an in-vehicle navigator which can reduce the load of image processing.

[0008]

SUMMARY OF THE INVENTION In the present invention, the above problems are solved by referring to map data storage means for storing map data, vehicle position detection means for detecting a vehicle position, and map data before departure. Search means for obtaining the optimum guidance route connecting the ground to the destination and road data around the intersection on the guidance route, and guidance for storing the guidance route data searched by the search means and the road data near the intersection on the guidance route Based on the route memory, the vehicle position data detected by the vehicle position detecting means during traveling, and the data stored in the guide route memory, the image of the guide route around the vehicle position and the road near the intersection on the guide route is displayed. This is achieved by providing road image display control means for displaying on the display means together with the mark.

[0009]

According to the present invention, by referring to the map data before departure, the optimum guidance route connecting the departure point to the destination and the road data around the intersection on the guidance route are obtained and stored in the guidance route memory. During traveling, based on the vehicle position data and the data stored in the guide route memory, an image of the guide route around the vehicle position and the road near the intersection on the guide route is displayed on the display means together with the vehicle position mark. As a result, the driver can be shown the route to the destination only by displaying the road image around the vehicle position using the data of the guide route memory, and the map data around the vehicle position can be read from the CD-ROM to display the screen. Since it is not necessary to display roads, buildings, rivers, etc. on the whole, the burden of image processing is reduced. Therefore, it is easy to execute other high-level image processing such as head-up display or traveling direction display at an intersection existing ahead of the vehicle traveling direction on the guide route.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of an essential part of an in-vehicle navigator according to an embodiment of the present invention.

In the figure, 1 is a CD-ROM that serves as map data storage means, 2 is an operation panel, and cursor keys for left, right, up, and down directions, route guidance mode setting keys, departure point setting keys, and destinations It is equipped with setting keys, map search, enlargement / reduction keys, start key, etc. Reference numeral 3 denotes a vehicle position detector having a heading sensor and a distance sensor, which detects the vehicle position and the vehicle heading by integral navigation every time the vehicle travels a certain distance and outputs the vehicle position data and the vehicle heading data.
It is a display device, which displays a map image of roads, buildings, rivers, etc. and cursor marks on the screen by inputting a video signal, a guide route and a road near an intersection on the guide route,
The vehicle position mark and intersection guidance image are displayed.

Reference numeral 10 denotes a navigation controller, which determines the optimum guide route from the starting point to the destination by simulation calculation, displays a map of roads, buildings, rivers and cursor marks on the CRT display device 4, The guidance route around the vehicle position, the road near the intersection on the guidance route, the vehicle position mark, and the intersection guidance image are displayed on the screen of the CRT display device 4. Of these, 11 is a buffer memory for temporarily storing the map data read from the CD-ROM 1, 12 is a cursor position calculation unit, and the cursor keys on the operation panel 2, the map search keys, the keys for enlarging / reducing the map, etc. When the selection operation or cursor operation is performed, the longitude and latitude corresponding to the center of the map on the screen are calculated and output as the cursor position. 1
Reference numeral 3 is a map drawing control unit which, before starting traveling, prints desired map data (which may include peripheral map data) selected by a key such as map search and enlargement / reduction key of the operation panel 2 on the CD- Reading from the ROM 1 to the buffer memory 11 and drawing a map image on a first V-RAM described later,
As the cursor position input from the cursor position calculation unit 12 changes according to the cursor operation, new map data is transferred from the CD-ROM 1 to the buffer memory 1 as necessary.
1 while rewriting the map image in the first V-RAM so that the cursor position is always in the center,
-Draw a cursor mark in the center of RAM. Further, the map drawing control unit 13 is traveling in the guide route mode (operation panel 2
After the start key is pressed), the vehicle position data and the vehicle direction data are input from the vehicle position detection unit 3, the road data around the vehicle position is read out from the guide route memory described later, and the vehicle position is at the center, and A road image is drawn in the first V-RAM so that the vehicle traveling direction indicated by the vehicle direction is upward, and a vehicle position mark is drawn in the center.

Denoted at 14 is a departure point / destination setting section, which is set to a route guidance mode by the operation panel 2 before the start of traveling, and after the cursor on the center of the screen is made coincident with the departure point by the operation of the operation panel 2, When the departure point setting key is pressed, the output of the cursor position calculation unit 12 at that time is set as the departure point data, and after the cursor on the center of the screen is matched with the destination by the operation of the operation panel 2, the destination is set. When the setting key is pressed, the output of the cursor position calculation unit 12 at that time is set as the destination data.

Reference numeral 15 is a search unit, which is used to set a departure place and a destination in the route guidance mode.
Departure data and destination data are input from the destination setting unit 14, various map data (road layers) from the origin to the destination are read from the CD-ROM 1 to the buffer memory 11, and the simulation on various routes is performed. Calculation is performed, and in this embodiment, the shortest distance is used as an index (otherwise, the shortest time may be used as an index) to find an optimum guide route connecting the departure place to the destination, and the map data is present on the guide route. While finding the intersection node, all the other nodes (intersection composing nodes) at the other end linked to the intersection node are searched for road data near the intersection on the guide route.

Reference numeral 16 is a guide route memory for storing guide route data and road data in the vicinity of an intersection on the guide route.
As shown in FIG. 2, the guide route memory 16 stores a node sequence forming the guide route together with the start point data and the final destination data. Each node data forming the node sequence includes the coordinates of longitude and latitude and the intersection identification flag R. Then, corresponding to the node having the intersection identification flag R of 1, the intersection constituent nodes forming the intersection are stored. The intersection constituent node data is composed of coordinates of longitude and latitude. In FIG. 2, the departure point data, the node N ₁ , the node N ₂ , the node N ₃ , ..., The destination data are the guide route data. Further, the node N ₃₁ , the node N ₃₂ , the node N ₃₃ , and the node N ₃₄ together with the node N ₃ form road data in the vicinity of the intersection N ₃ on the guide route.

An intersection guidance control unit 17 inputs vehicle position data from the vehicle position detection unit 3 and refers to the guidance route data stored in the guidance route memory 16 to refer to the forward direction of the vehicle on the guidance route. The two intersections whose traveling directions are to be changed are searched for from the one close to the vehicle, and a predetermined intersection guidance image is drawn in the second V-RAM.

The traveling direction at the intersection is the guidance route memory 1
For the intersection node in the guide route data of 6, the node before (entry node) and the node after (exit node)
And calculate the direction (straight turn, left turn, right turn) to run at the intersection from these positional relationships. Specifically, as shown in FIG. 3, the angle θ of the exit node is determined in the clockwise direction with the half line extending from the intersection node toward the approach node as the reference direction, and 0 ° ≦ θ ≦ When 135 °, turn left. When 135 ° <θ <225 °, go straight. When 225 ° ≦ θ <360 °, turn right. Of the intersections calculated as left turn or right turn, two are closest to the vehicle position as guidance candidates.

Then, the intersection guidance control unit 17 calculates the intersection number of the guidance candidate intersection from the vehicle position, for example, "turn left at the first intersection, turn right at the third intersection". Then, an intersection guidance image in which the position and direction of the intersection for changing the traveling direction is expressed by characters is drawn on the second V-RAM described later.

Reference numeral 18 denotes a first V-RAM, which is an image drawn by the map drawing control unit 13 (when a cursor is operated before the start of running, a map image of a road, a building, a river, etc. and a cursor mark, and running under a route guidance mode. The inside stores the guide route and roads and vehicle position marks near intersections on the guide route. Reference numeral 19 denotes a second V-RAM, which is an intersection guidance control unit 2
The intersection guidance image drawn in 1 is stored. A synthesizing unit 20 outputs the map image read from the first V-RAM 18, and synthesizes the map image read from the first V-RAM 18 with the intersection guidance image read from the second V-RAM 19 and outputs the image.

The intersection guidance image drawn in the second V-RAM 19 has a size of, for example, 1/24 of the screen, and is synthesized by the synthesis unit 20 at a position corresponding to the right corner of the screen. ..

Reference numeral 21 is a video conversion unit that converts the image data output from the synthesis unit 20 into a video signal and outputs the video signal to the CRT display device 4.

4 and 5 are flow charts showing the operation of the navigation controller 10, FIG. 6 is a road map of a range including a starting point to a destination, and FIG. 7 is an explanatory view showing a display example of a screen of the CRT display device 4. Therefore, description will be given below with reference to these figures.

First, when a map search operation of the operation panel 2 and a selection operation of a map of a desired area at a desired scale are performed by operating keys for enlarging / reducing, the map drawing control unit 13 causes the desired map from the CD-ROM 1. The data is read to the buffer memory 11 and the map image is drawn on the first V-RAM 18. The map image data drawn in the first V-RAM 18 is output to the video converter 21 via the synthesizer 20, converted into a video signal by the video converter 21, and then the CRT display device 4 is displayed.
Is output to. The CRT display device 4 displays a map on the screen based on the input video signal (steps 101 and 102 in FIG. 4). Then, when the cursor key of the operation panel 2 is operated after the route guidance mode setting operation is performed on the operation panel 2, the cursor position calculation unit 12 calculates the cursor position (coordinates of longitude and latitude) (step 103-10
6), the map drawing control unit 13 draws a map image on the first V-RAM 18 while reading the predetermined map data from the CD-ROM 1 into the buffer memory 11 in accordance with the change in the cursor position so that the center is always at the cursor position. At the same time, a cursor mark is drawn in the center of the first V-RAM 18. As a result, the map on the screen moves in accordance with the cursor operation while the cursor mark is displayed in the center of the screen (steps 107 and 108).

When the cursor mark on the screen reaches the destination, the cursor operation is temporarily stopped and the destination setting key of the operation panel 2 is pressed. The cursor position data output from is set and registered as destination data (steps 109 and 110). Next, perform the cursor operation again to move the map on the screen. When the cursor mark comes to the departure point, stop the cursor operation once and press the departure point setting key on the operation panel 2 to set the departure point / destination Part 1
4 sets / registers the cursor position data output from the cursor position calculation unit 12 at that time as departure point data (steps 111 and 112).

In this way, when the setting / registration of the departure point data and the destination data is completed (YES in step 113).
(Determination in S), the departure place data is output to the vehicle position detection unit 3, the map drawing control unit 13, and the intersection guidance control unit 17, and the vehicle position detection unit 3 uses the departure place data as the starting point of the integral navigation.
Based on the departure point data and the destination data, the search unit 15 selects C
While reading the map data (road layer) from the starting point to the destination from the D-ROM 1 to the buffer memory 11, referring to the map data, the simulation calculation is repeated, and the optimum is the shortest distance from the starting point to the destination as an index. 5 to find an appropriate guide route (step 201 in FIG. 5), find an intersection node on the guide route from the map data, and read out the intersection constituent nodes (all the nodes at the other end of the link forming the intersection) to determine the vicinity of the intersection. Road data is obtained (step 202). Then, the searched guidance route data (node sequence including the starting point data at the tip and the final destination data) and the road data near the intersection on the guidance route are stored in the guidance route memory 16 as shown in FIG. 2 ( Step 203).

When the start key is pressed on the operation panel 2 to start traveling, the map drawing control section 13 detects the departure point data set by the departure point / destination setting section 14 and the vehicle position detection section 3. Based on the obtained vehicle direction data, the guidance route memory 16 reads the guidance route data around the departure point and the road data near the intersection on the guidance route, and the departure point is at the center and the vehicle traveling direction indicated by the vehicle direction is upward. Then, the road image is drawn on the first V-RAM 18 (steps 204 and 205). And the first V-RAM
A vehicle position mark is drawn in the center of 18 (step 20)
6). The image drawn in the first V-RAM 18 is the combining unit 2
It is directly output to the video converter 21 via 0, converted into a predetermined video signal, and output to the CRT display device 4. As a result, the screen shows the departure point (current position of the vehicle)
A road image in the vicinity of the intersection around the guide route centered at is displayed, and at a glance it is possible to know what route to take. Here, if only the guide route is displayed on the screen, it becomes difficult for the driver to understand the intersection to be changed and the traveling direction, but it is easier to understand by displaying the roads near the intersection on the guide route together. In addition,
The guide route and the road near the intersection on the guide route may be displayed in different colors.

Next, the intersection guidance control unit 17 determines, based on the departure point data and the guidance route data stored in the guidance route memory 16, that the intersection where the traveling direction is to be changed ahead of the vehicle on the guidance route is closer to the vehicle. Find one, calculate the number of intersections from these vehicles for these two intersections,
A predetermined intersection guidance image is drawn on the second V-RAM 19 (step 207). At first, as is clear from Fig. 6, "turn left at the first intersection and turn right at the third intersection"
Becomes

The intersection guidance image drawn in the second V-RAM 19 is combined by the synthesizing unit 20 with the road image drawn in the first V-RAM 18 and output to the video converting unit 21. Therefore, the screen becomes as shown in Fig. 7 (1), and the position of the intersection to the intersection to be changed and the traveling direction at the intersection are shown in the lower right corner, so the driver can easily follow the guidance and drive. It is possible to travel toward the destination correctly on the route.

When the vehicle starts traveling, the vehicle position detecting section 3 calculates the vehicle position and the vehicle direction by integral navigation from the starting point every time the vehicle travels a certain distance, and outputs the vehicle position data and the vehicle direction data. Navigation controller 1
When the vehicle position data 0 and the vehicle direction data are input from the vehicle position detection unit 3 (step 208 in FIG. 5), the map drawing control unit 13 determines, based on the vehicle position data and the vehicle direction data, from the guide route memory 16 that the vehicle position vicinity is present. Of the guide route data and the road data in the vicinity of the intersection on the guide route are read, and the road image is drawn in the first V-RAM 18 so that the vehicle position is in the center and the vehicle traveling direction indicated by the vehicle direction is upward. (Step 209). And the first V-
A vehicle position mark is drawn in the center of the RAM 18 (step 206).

Further, the intersection guidance control unit 17 determines, based on the vehicle position data and the guidance route data stored in the guidance route memory 16, that the intersection where the traveling direction is to be changed ahead of the vehicle on the guidance route is closer to the vehicle. Find one, calculate the number of intersections from these vehicles for these two intersections,
A predetermined intersection guidance image is drawn on the second V-RAM 19 (step 207). The intersection guidance image is the same as before when the vehicle has not yet started traveling and has not passed the first intersection to be rerouted. The road image drawn on the first V-RAM 18 and the intersection guidance image drawn on the second V-RAM 19 are combined by the combining unit 20 and then sent to the video converting unit 21 to be converted into a predetermined video signal for CRT display. It is output to the device 4. As a result, in the road image on the screen, the map scrolls in the direction opposite to the traveling direction of the vehicle with the center of the vehicle position.

When the processing of step 207 is completed, the navigation controller 10 waits for the next input of vehicle position data and vehicle azimuth data. Then, when there is an input, similarly to the above, first, the map drawing control unit 13 causes the vehicle position to be in the center and the vehicle traveling direction to be the first V-.
A road image around the vehicle position is drawn in the RAM 18, and a vehicle position mark is drawn in the center. Subsequently, the intersection guidance control unit 17 displays the intersection guidance image in the second V-RAM 19.
Draw on. Road image of the first V-RAM 18 and the second V-
The intersection guidance image of the RAM 19 is synthesized by the synthesis unit 20,
After being converted into a video signal by the video converter 21, the video signal is output to the CRT display device 4. When the vehicle passes the first crossing to change course, the screen changes as shown in FIG. 7 (2).

Hereinafter, the same processing is repeated every time the vehicle travels a certain distance, and when the destination is reached,
Finish route guidance.

[0033]

As described above, according to the present invention, the map data storage means for storing the map data, the vehicle position detecting means for detecting the vehicle position, and the map data before the departure are referred to so that the route from the departure point to the destination is referred to. A search means for obtaining the optimum guide route connecting the roads and road data around the intersection on the guide route; a guide route memory for storing the guide route data searched by the search means and road data near the intersection on the guide route; Based on the vehicle position data detected by the vehicle position detecting means and the data stored in the guide route memory, the image of the guide route around the vehicle position and the road near the intersection on the guide route is displayed on the display means together with the vehicle position mark. Road image display control means to be displayed is provided, and by referring to map data before departure,
The optimum guidance route connecting the departure point to the destination and the road data around the intersection on the guidance route are obtained and stored in the guidance route memory, and while traveling, based on the vehicle position data and the data stored in the guidance route memory, Since the image of the guide route around the vehicle position and the road near the intersection on the guide route is displayed on the display means together with the vehicle position mark, only the road image around the vehicle position is displayed using the data of the guide route memory. It is possible to show the driver the route to the destination, read the map data around the vehicle position from the CD-ROM, and do not have to display roads, buildings, rivers, etc. on the entire screen. Is less. Therefore, it becomes easy to execute other high-level image processing such as head-up display and traveling direction display at an intersection existing in the forward direction of the vehicle on the guide route.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of an in-vehicle navigator according to an embodiment of the present invention.

2 is an explanatory diagram showing a configuration of data stored in a guide route memory shown in FIG. 1. FIG.

FIG. 3 is an explanatory diagram showing a method of calculating an intersection traveling direction by the intersection guidance control unit of FIG. 1.

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

5 is a second flowchart showing the operation of the navigation controller of FIG. 1. FIG.

FIG. 6 is a road map including a starting point and a destination.

FIG. 7 is an explanatory diagram showing a screen display example of the CRT display device of FIG. 1.

FIG. 8 is an explanatory diagram of road data stored in a CD-ROM.

[Explanation of symbols]

 1 CD-ROM 3 vehicle position detection unit 4 CTR display device 10 navigation controller 13 map image drawing control unit 15 search unit 16 guide route memory 17 intersection guidance control unit

Claims (1)

Claims: 1. A map data storage means for storing map data, a vehicle position detection means for detecting a vehicle position, and a map data before departure, referring to the map data to search from a departure place to a destination. Search means for obtaining the optimum guide route to be connected and road data around the intersection on the guide route, a guide route memory for storing the guide route data searched by the search means and road data near the intersection on the guide route, and , Based on the vehicle position data detected by the vehicle position detecting means and the data stored in the guide route memory, the image of the guide route around the vehicle position and the road near the intersection on the guide route is displayed on the display means together with the vehicle position mark. An in-vehicle navigator, which is provided with a road image display control means for controlling the road image display.