JP2905491B2 - Navigation device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation device that sets a route by performing a route search from a designated departure point and a destination and provides route guidance.

[Conventional technology]

2. Description of the Related Art A navigation device performs route guidance to a destination for a driver who is unfamiliar with geography. In recent years, a navigation device that provides travel guidance of various vehicles has been proposed. These navigation devices set a route from a departure place to a destination by inputting a departure place and a destination before traveling, and perform navigation (route guidance) according to the set route. In this navigation, a map is drawn on the CRT screen and a route is superimposed and displayed on the map.Some of the information is information on the intersection to turn next according to the preset route, until the intersection to turn next The remaining distance is displayed as a number or graph, the direction of travel at an intersection to be turned is displayed, or a characteristic photograph is displayed. Further, there is also a display that uses audio output together with these displays.

[Problems to be solved by the invention]

By the way, in such a navigation device, a route search is performed by designating a departure place and a destination, and for a route set as a result, for example, it is necessary to know what kind of route it is. There is also a situation in which the user may want to know the current position of the vehicle because he or she may be rough in the entire route, or may want to know where he / she is traveling when he / she deviates from the route while traveling. In such a case, displaying the entire route from the departure point to the destination is useful information. In addition, when the set route is known, the same is applied to a case where a request to change the route to another route instead of the route is satisfied. After the route is displayed, for example, the user is instructed to select the next rank for the searched route. There is a method that can be used.

However, the conventional navigation device has information such as roads, intersections, and features as navigation data, performs a route search by processing such information, selects and sets a route, and forms one type of route guidance. Rendering and display of the map does not sufficiently respond to each of the above requirements. In addition, even when drawing a map, the data required at each time is selected from the data of all the areas prepared for navigation, the map drawing information is read, and the node strings are connected by an arc. The map is drawn by. For this reason, the amount of data to be read is increased, and a lot of time is required for processing, and it may take several seconds to draw a map.

In addition, as a method for easily determining the scale and displaying the map, the separation distance between the designated destination and the obtained current position is calculated, and the scale of the map is determined based on the separation distance to include the current position of the vehicle. The one that displays a map (for example,
JP-A-59-206710), the distance and positional relationship between the departure point and the destination are determined to determine a predetermined scale, and the name of the place corresponding to the coordinates and the mark of the departure point and the destination are determined based on the scale. (See, for example, JP-A-60-188812 and JP-A-60-194310).
However, in these methods, since the scale is determined based on the coordinates of the two points, the current position, the departure point, and the destination, so that both points enter the display screen, both points are displayed together and the positional relationship is displayed. However, for example, when there is a mountain or lake, etc., and the route is largely detoured, a part of the route will be off the screen and cannot be displayed, and it will not be possible to grasp the entire route. The problem arises.

The present invention solves the above-described problem, and provides a navigation device that draws a map of an optimal scale at high speed by simple processing and can display the map on the map without protruding from a set route. It is intended to provide.

[Means for solving the problem]

The present invention has been made in view of the above circumstances,
In a navigation device for setting a route and performing route guidance by performing a route search from a designated departure point and destination, for example, as shown in FIG. 1, drawing map data (23) for displaying a route and road data (22) And these are
As shown in FIG. 3, upper-layer basic drawing map data ((a)) corresponding to the maximum drawing area as drawing map data for route display, and a plurality of lower-layer areas obtained by dividing the area of the basic drawing map data Enlarged map data ((b) ~
(G)) is stored as data having a hierarchical (layer) structure, and the data processing control unit (16) selects, from the set route, basic drawing map data or enlarged drawing map data in which the route falls within the drawing range. In which a map is drawn and a route is displayed thereon.

The reference numerals in parentheses correspond to those in the drawings, but do not limit the configuration.

[Action and effect of the invention]

In the navigation device of the present invention, basic drawing map data ((a)) corresponding to the maximum drawing area as drawing map data for route display, and enlarged drawing map data ((b) of a plurality of areas obtained by dividing the basic drawing map data. ) To (g)), and a map is drawn by selecting basic drawn map data or enlarged drawn map data in which the route falls within the drawing range from the set route. By comparing the area including the route to be displayed with the area of the drawn map data, the optimum drawn map data can be selected and drawn, and the amount of data processing can be reduced. Therefore, the speed of the route display can be increased, and the route display can be appropriately performed according to the user's request.

〔Example〕

 Hereinafter, embodiments will be described with reference to the drawings.

FIG. 1 is a diagram for explaining an embodiment of a navigation device according to the present invention, FIG. 2 is a diagram showing a display example, FIG. 3 is a diagram showing an example of division of drawn map data, and FIG. It is a diagram for explaining the flow of, in the figure, 11 is a distance meter, 12 is a steering angle meter, 13 is an input unit, 14 is an input decoding unit, 15 is an input decoding table, 16 is a data processing control unit, 17 Is the image output controller,
Reference numeral 18 denotes a display unit, and 21 to 23 indicate files.

The distance meter 11 measures the traveling distance of the vehicle,
For example, one that detects and counts the rotation of a wheel, one that detects acceleration and integrates twice, and the like may be used, but other measuring means may be used.

The steering angle meter 12 detects whether or not the vehicle has turned at an intersection.For example, an optical rotation sensor or a rotation-type resistance volume attached to a rotating portion of a steering wheel can be used. An attached angle sensor may be used.

The input unit 13 may be a joystick, a key, or a touch panel, or may be a unit connected to a screen of the display unit 18 to display a key or a menu on the screen and input from the screen.

The input decryption unit 14 is for decrypting the data input from the input unit 13 while referring to the input decryption table 15,
For example, when setting a route, the starting point (current position)
When a destination or a destination is input by a telephone number or by a code, a menu, or another mode, conversion to departure point data or destination data is performed by referring to the input decoding table 15 according to the mode. In the case of input of help or other instruction other than the input of the position such as the departure place and the destination, it goes without saying that the corresponding processing is performed. Therefore, the input decoding table 15 is set in accordance with data to be input from the input unit 13 as to what kind of input is given.

When a destination and a departure place are input from the input unit 13, the data processing control unit 16 searches and sets a route connecting the two points from the road data, and executes a navigation program for the route stored in the file 21. Call and execute. Also,
When the route is set, drawing map data is selected and drawn from the route data in response to a user request, and the route is displayed thereon. The navigation program displays a guide map on the screen of the display unit 18 along the traveling route,
It is configured to display a characteristic photograph at an intersection or a route, display the remaining distance to the intersection, the traveling direction at the next intersection, and display other guidance information. The files 22 and 23 store road data and map data for that purpose, and the image output control unit 17 controls output of images to the display unit 18. In particular, according to the present invention, rather than drawing a map from basic data such as node string data based on a route set as in the related art and displaying the route, some drawn map data are prepared in advance. , And selects the most suitable drawing map data for displaying the set route.

For this reason, so-called navigation map data and road data, which provide route guidance along the way as the vehicle travels, and these data for route display are separately provided. This is because the route display is intended to provide the user with a rough overall route from the departure point to the destination, so as to capture a characteristic photograph as described above, to calculate the remaining distance to the intersection, This is because the content and the amount of data are different from the navigation data that displays the traveling direction to the next intersection or displays other guidance information to provide detailed information along the route. However, in the case of drawing map data of a narrow area (local), there is a case where the navigation data can be used as it is. In such a case, the navigation data is used without preparing the route display data. Route may be displayed.

FIG. 2 shows an example of the route display displayed by the route set as a result of the route search. FIG. 2A shows the drawing of the drawing map data and the display of the route using the Chubu area as the drawing unit area. An example is shown, and vertical and horizontal lines indicate dividing lines. In this screen, the route is displayed in the upper left corner. According to the present invention, in such a case, the drawing map data divided into 16 as shown in FIG. But,
When the route extends over the entire area, the route is displayed by drawing map data of a wide area as shown in FIG.

FIG. 3 shows an example of division of the drawing map data.
FIG. 3A shows basic drawing map data. Since this drawing map data is a wide-area drawing, it consists of data for displaying, for example, a coastline, a highway, an expressway, and a major city (location). On the other hand, FIG. 3B is a diagram obtained by dividing the basic drawing map data of FIG. 3A into four parts, and FIGS. 3C to 3E each have one size in the vertical, horizontal and vertical directions. It is shifted by / 2 pitch. To these drawn map data, a representative city name is added to a coastline, an arterial road, an expressway, and a main city (location). FIG. 1F shows the basic drawing map data of FIG. 1A divided into 16 parts, and FIG. 1G shows the same size shifted by 1/2 pitch vertically and horizontally by the same size. In this way, a total of 35 pieces of drawing map data are prepared in advance with the display screen size, and the drawing map data that is the smallest and includes the route at the center from the set route is selected and drawn.
These drawn map data include data for displaying coastlines, national roads, expressways, national road numbers, representative city names, and the like. Assuming that FIG. 3 (a) is the uppermost layer, FIGS. 3 (b) to (e) are the lower layers, and FIGS. 3 (f) and 3 (g) are the lower layers. By adopting a so-called layer structure, the display information is increased as the area becomes narrower according to the drawing area, so that local information can be provided. In addition, FIG.
FIG. 2G shows all the dividing lines in FIG.
Shows this dividing line.

Next, a process of displaying a route based on route data from a departure place to a destination will be described with reference to FIG.

First, in a step, the route road number of the route data is input, and in the step, a node string is read from this road number. Next, in a step, a range of north, south, east and west (maximum and minimum of X coordinate, maximum and minimum of Y coordinate) is calculated. That is, here, a rectangular area based on the end point on the route is obtained. Therefore, when displaying not only a map in which the north direction is always up, but also a map in which the direction is rotated so that the traveling direction is up, for example, the horizontal direction (X Coordinate maximum and minimum) and vertical direction (maximum Y coordinate,
(Minimum) range. Then, in a step, the optimum drawing map data which falls within this range is selected from the respective drawing map data as shown in FIG. 3, and in the step, the nodes are converted into screen coordinates, and in the step, a map is drawn. The route is displayed according to the route data on the map drawn in this manner. The route display of the present invention can be used at any time after the route is set by inputting the departure place and the destination in the navigation device. For example, as the approaching destination approaches the current location as the departure place, For example, a map and a route from the current location to the destination can be displayed by replacing and updating the departure location with the current location.

The overall flow of the navigation apparatus will be described with reference to FIG. 4 (b). First, in the step of inputting the departure place, the present location is input from a pre-stored list of registered locations. At this time, if the current location is not in the registered location list, the nearest registered location is selected, and the position is set as the initial departure location.

Subsequently, in a step, a destination is similarly input from the registered location list.

When the departure point and the destination are input, in step, a route from the departure point to the destination is searched based on the intersection data and road data stored in advance and the road network data including these node string data. Then, the search result is stored, for example, as intersection sequence data in the route.

Then, in the guide map display of the step, while drawing map data is selected from the search route and drawn on the screen,
The route from the starting point to the destination is displayed based on the route data.

In the route display, for example, when it is desired to select another route different from the set route, not shown, the process returns to the step again, or a priority is assigned in the step, and a plurality of routes are sequentially selected as a candidate or as a selection menu. By displaying the information, the next-ranked route may be selected.

When the route is determined in this way, the navigation start instruction in the step sequentially takes a landscape photograph of the next guidance intersection, an intersection name, an intersection shape, a remaining distance there, a feature point in the landscape photograph, and a traveling direction there. And so on.

Also, during this route guidance, for example, every time the current position recognition means detects the passage of an intersection on the route or another predetermined check point, the current position is recognized, and the current position is repeatedly determined until the vehicle reaches the destination. Can be displayed on the route display screen as travel history information by, for example, changing the color of the route display. If such a display is obtained, it is possible to know the approximate current position on the route by appropriately switching to the route display even during traveling.

Similarly, for example, a help function is added to the navigation device, and when the help function is activated due to a deviation from the route or an instruction from the user, a route display including the traveling history information up to the present is performed instead of the guide display. You may do so.

Steps and are additional steps, and the former is an example of departure from a parking lot. In this case, the parking lot exit is set as the departure place, and the parking lot exit guidance is performed. In this guidance, the traveling direction at the exit of the parking lot and a photograph of the exit are displayed, and the start of the current position detection is manually input at the exit to start the current position recognition processing and the route guidance processing. Also, the latter step is to go from the destination to another destination or to end, and when going to another destination, arrive at the destination without inputting the departure place by simple specific instructions or operations This is a process of registering the completed destination as a departure place. In this way, when visiting a plurality of destinations sequentially, the input of the departure place can be simplified.

As described above, in the navigation system, when the departure point and the destination are input from the input unit 13 before traveling, the data processing control unit 16 performs a route search to select and set a route, and corresponds to the route. The navigation program is read from the file 21 and executed. Then, route display can be appropriately performed according to a user's request. The navigation program calculates and recognizes the position of the vehicle based on the measurement information from the distance meter 11 and the rudder angle meter 12 according to the route, displays the route guide map and the current position through the display unit 18 and the speaker 20, and displays the route during the passage. And guidance of intersections. When a route is displayed based on the recognition data, the own vehicle position recognized as the current position is displayed on the route on the drawing map. In the route guidance, for example, when the distance to the next intersection is long, in order to give the driver a sense of security that he does not deviate from the route in the middle of the route, a photograph of the passing feature is displayed on the screen. Projecting,
Alternatively, a guide map and the position of the own vehicle are displayed to inform the traveling position on the route. Then, when the intersection approaches, the intersection information is output by the screen or the voice as described above, and the voice instruction is output as appropriate.

 Next, an example of the structure of the drawing map data will be described.

FIG. 5 shows a structural example of a display data management table, FIG. 6 shows a structural example of road node column selection data, FIG. 7 shows a structural example of drawing map selection data, and FIG. Is a diagram showing an example of layer 1 and 2 road node data,
FIG. 9 is a diagram showing a structural example of drawing map data.

As shown in FIG. 5, the display data management table includes the address and size of the road node column selection data table shown in FIG. 6, the address and size of the drawn map selection data table shown in FIG. 7, latitude and longitude. , And the latitude and longitude corresponding to one dot on the display screen as information. Therefore, first, by accessing this table, it is possible to recognize the storage area size and storage address to be prepared when reading, for example, the road node column selection data table and the drawing map selection data table. The road node string selection data includes, for each road number, a road number, an address and a size of a road node string data table shown in FIG. 8, a starting point intersection offset address of the road, as shown in FIG.
It has information on the number of nodes between roads and the area size based on XY coordinates. As shown in FIG. 7, the drawing map selection data includes, for each drawing map data, a screen size based on XY coordinates, an address of the drawing map data table shown in FIG. 9, and information on the size.

A map is drawn using the drawn map selection data shown in FIG. 7 and the drawn map data shown in FIG. 9 among the above data. In addition, in FIG. 3, (a) is a layer 1,
(B) to (e) are layer 2 and (f) and (g) are layer 3
If a route is to be displayed on the map of layer 3, local detailed information is required as in the case of route guidance. However, in the case of Layer 1 and Layer 2, rough information is sufficient. In such a case, when a route is drawn on the map for Layer 1 and Layer 2, the road node string selection data shown in FIG. 6 and the road node string data shown in FIG. Can use the data for

The road number in the road node string selection data shown in FIG. 6 is assigned in units of route search, that is, as described later, as a unit from intersection to intersection. The column data is stored, for example, for each national road. Therefore, the road node string data shown in FIG. 8 includes a large number of road numbers of the unit for performing the route search. Therefore, if this national road information is included in the road node string selection data shown in FIG. 6, when the road node string data of the next road number is read, if the national road is the same, the data already read , It is possible to recognize that it is sufficient to extract the image data from the data, so that the reading process can be omitted, and the processing speed can be improved.

In the data structure as described above, when displaying a route based on the set route, first, the maximum value and the minimum value of the node sequence of the route by the XY coordinates are obtained. To draw a map, the display data management table is used to confirm that the size falls within the region size based on latitude and longitude, and then the drawing map selection data is read from the drawing map selection data table address into a storage area corresponding to the size. Then, the screen size based on the XY coordinates of each drawing map data is compared with the maximum value and the minimum value based on the XY coordinates of the node string of the route, and the drawing map data of the screen size including the route is extracted. In this case, if there are a plurality of drawing screen data, the number of divisions is set higher, and if the number of divisions is the same, drawing map data whose route is closer to the center of the screen is selected. That is, the drawing map data having the shortest distance between the center of the rectangle formed by the maximum value and the minimum value of the node array of the path by the XY coordinates and the center of the drawing map data is selected. When the drawing map data is selected by the drawing map selection data in this manner, the drawing map data is read from the drawing map data table address into the storage area corresponding to the size, and the shoreline node row, the prefectural border node row, the national road node row The map is drawn by drawing each data of a highway node column, a national road number, and a city name.

Then, when displaying the route on the drawn map, the road node column selection data is read from the road node column selection data table address of the display data management table, and the road number of the route is matched. Then, the road node data is read from the road node row data table address of the road number, a predetermined node row is extracted from the number of inter-road nodes from the start intersection offset address, and displayed on the map. This is performed from the starting point to the destination in the order of the routes.

In the case of the route display, as described above, since the display is a rough display over a wide area, in particular, FIGS. 3A to 3E are used.
For maps of the upper layer such as, processing efficiency is improved by separately preparing and processing data different from the navigation data as shown in FIGS. 6 and 8, but FIGS. For the map of the lower layer as shown in ()), the area becomes narrower and detailed information is required, so that navigation data may be used.

According to the present invention, as described above, a route search is performed by inputting a departure point and a destination, and a map of an optimal area for displaying the route is set in advance for a route set. The user selects and draws from the prepared drawing map data and displays a route thereon. Accordingly, the applicant has already filed separate applications (Japanese Patent Application Nos. 63-207762, 62) for the route search and the help function utilizing the present invention.
-333056) will be described as an example.

FIG. 10 is a diagram for explaining one embodiment of the route search method.

In FIG. 10, layer 31 includes intersection numbers I, II, II
It is a map of the main arterial road network having I,..., And is composed of one block a. The layer 32 is a map including a road network of branch lines connected to the main trunk road network of the layer 21, and is composed of six blocks a to f. Then, on the connecting road between the blocks, pseudo intersections are set such that the processing unit can be constituted by the blocks, such as the intersection numbers V and II between the blocks a and b of the layer 32. The number of blocks is set so that the amount of information is substantially the same for each. Accordingly, the block a of the layer 31 and the blocks af of the layer 32 have the same information amount as road network data.

As described above, the route search method of the present invention uses a map data having a hierarchical structure including layers 31, 32,... This is to search for a route from to the destination. Therefore, if there is a branch road further below the layer 32 road network, the layer 33 (not shown) is set. In this case, since more local information is added, the number of blocks increases according to the amount of information. Similarly, when not only the block a of the layer 31 but also the surrounding road network is targeted, the layer 31
And blocks of the road network around it. Then, in this case, a layer higher than the layer 31 is set.

In the road data shown in FIG. 10, for example, it is assumed that the departure point and the destination are respectively the intersection number I in the block a of the layer 32 and the intersection number III in the block f.

First, the departure point of the intersection number I in the block a is an intersection number that does not exist in the layer 31 of the upper hierarchy. Then, find the intersection number in layer 31 of the upper hierarchy,
The intersection numbers III and IV (intersection numbers I and I
Search for the route to I) and go up to the upper level.

On the other hand, since the intersection number III in the block f is the intersection number VIII in the layer 31 of the upper hierarchy, it goes up to the upper hierarchy as it is.

In the upper layer 31, the intersection number I or II is added to the intersection number together with the information searched for in the lower layer 32.
Perform a route search to VIII.

As is clear from the above example, according to the blocks where the departure place and the destination exist, the blocks can be classified into three types: the same block, the adjacent block, and the distant block. Therefore, the route search method of the present invention performs a route search as follows according to each.

First, when the starting point and the destination are in the same block, a route search is performed in the block. Also, if the starting and destination blocks are adjacent,
An intersection (connection intersection) where the departure point block and the destination block are connected is detected, and a route search is performed in two stages, a connection intersection from the departure point and a connection intersection from the destination. However, when the departure point and the destination block are separated from each other, a search is performed from the departure point to the intersection connected to the upper layer in the departure point block as in the above example,
Similarly, a search is performed in the destination block from the destination to the intersection connected to the upper layer. Then, the same route search is sequentially performed on the upper layer until the above or the above condition is satisfied.

Next, a specific structure example of road data suitable for use in the above route search method will be described.

FIG. 11 is a diagram showing an example of the data structure of block a in layer 32 of FIG. 10, FIG. 12 is a diagram showing an example of the data structure of block d in layer 32 of FIG. 1, and FIG.
FIG. 14 is a diagram showing an example of the data structure of the block f in the layer 32 in FIG. 14, and FIG. 14 is a diagram showing an example of the data structure of the block a in the layer 31 in FIG.

The data in each block unit is composed of road data (FIG. 11A) and intersection data (FIG. 10B) as shown in FIGS. Then, for example, as shown in FIG. 11, the road data includes the intersection number of the starting point, the intersection number of the ending point, the road number having the same starting point, the road number having the same ending point, the guidance information corresponding to each road number in the block. Information such as unnecessary roads, relative lengths of roads, and layers is stored. The unit of the road number usually consists of a plurality of nodes. The node data, which is not shown, is data relating to one point on the road, and what connects the nodes is called an arc.
A road is represented by connecting each of the plurality of node rows with an arc. In addition, the intersection data includes east longitude, north latitude, outgoing road number, incoming road number, intersection number of upper layer, intersection number of lower layer, intersection number of horizontal block (connection (Intersection number).

Among these, the road number having the same start point (end point) and the road number exiting (entering) are information of connecting roads at the intersection, respectively. Usually, since there are a plurality of road numbers, the smallest road number among them is provided. Is registered. This makes it easy to search for a connecting road at an intersection as described later. Further, the relative lengths of the guide-unnecessary roads and roads are information necessary for calculating a substantial time required for traveling. For example, even if the roads have the same width and length, the actual travel time can be converted into a shorter travel time on a road that does not require guidance than a road that requires guidance. Or if the road is easily congested, the relative length will be long. The layer indicates the rank of the road. That is, the information indicates the order of the layer of the road. Intersection number of the upper (lower) layer, for example, 1
-1-2 indicates the layer 31 (2 in the case of the layer 32) -block a (2 in the case of the block b,... 6 in the case of the block f) -intersection number in the layer block I have. The same applies to the intersection numbers of the horizontal blocks.

 Next, the route search method will be described according to the processing flow.

FIG. 15 is a diagram showing the structure of a work file and an index file, FIG. 16 is a diagram for explaining the overall processing flow in a route search, FIG. 17 is a diagram showing an example of the same block search routine, FIG. The figure shows an example of an adjacent block search routine, and FIG. 19 shows an example of a remote block search routine.

When searching for work files in block units,
The intersection data and the road data in the block are read and used. As shown in FIG. 15 (a), the number of intersections, the number of roads, the start point, the end point, the road number entering the intersection obtained from the block search result, the block And information such as a flag indicating a starting point and a destination of the search. The index file manages block information, and has information such as the number of blocks and the block number as shown in FIG.

As shown in FIG. 16, in the route search, first, the positional relationship between the departure place and the destination block is checked using an index file, and the following same block search is performed based on the positional relationship.
The process branches to either the adjacent block search routine or the remote block search routine.

In the same block search, as shown in FIG. 17, intersection data and road data are input, a word query is initialized, and a departure place and a destination are set. Thereafter, the flow branches to a route search subroutine, and the route generated there is output.

In the adjacent block search, the intersection number is expressed in the form of C (layer-block-intersection number), the road number is expressed in the form of R (layer-block-road number), and the departure point is C (2-1-
1) Assuming that the destination is C (2-4-4), the following processing is performed in the steps shown in FIG.

Read the data of layer 2 and block 1 where the departure point is.

 The connection intersection S is stored in the memory as described below.

All the intersections in the block in the work area are set and initialized as follows.

Road coming to the intersection ← 0 Flag ← Not searched Distance ← 7FFFFFFFH Departure intersection C in the work area (2-1
"Tentative" is set in the flag of 1), and "0" is set in the distance.

Continuous intersection (2-1-6), C (2-
1-7) is set.

A search is performed from the departure point intersection C (2-1-1) to the continuous intersection (2-1-6) and C (2-1-7), which are temporary destinations.

Save the work area. At this time, the distance to the connecting intersection is stored in the memory as described below.

A search similar to that described above is performed with the departure point as C (2-4-1) and the destination as connection intersections C (2-4-5) and C (2-4-4).

-Select the connection intersection that is the shortest route. For example, the distance from the departure point and the distance from the destination , The connecting intersections are C (2-1-6) and C (2-4-4) whose distances are shorter from (6 + 5) <(11 + 8).
5).

Route C (2-4-1) -C (2-
4-5) is created.

~ Load the work area, and route C (2-1-1) -C (2-1-3) -C (2-1-
6) is created.

By synthesizing each of the above routes, C (2-1-1)
-C (2-1-3) -C (2-1-6)-(2-4-
1) Output -C (2-4-5).

Subsequently, search for a remote block will be described. Here, it is assumed that the departure place is C (2-1-1) and the destination is C (2-6-2).

Write data of layer 2 and block 1 where the departure point is.

 A connection intersection S2 to a higher layer is detected.

~ Departure point is C (2-1-1), destination is C (2-1-1)
1-3), search as C (2-1-4) and save the work area.

The distance from the departure point to the connection intersection S2 is stored in the memory.

-Data of layer 2 and block 6 having a destination are read.

 The connection intersection D2 to the upper layer is detected.

~ The starting point is C (2-6-2) and the destination is C (2- 6-2).
6-1), search as C (2-6-3) and save the work area.

The distance from the departure point to the connection intersection D2 is stored in the memory.

-Data of upper layer 1 and block 1 are input.

Intersection S2 (C (1-1-1), C
(1-1-2)) is set. In addition, the distance from the departure point to the connection intersection S2 is set as the initial distance.

Connection destination D2 (C (1-1-7), C
(1-1-8)) is set.

Connection intersection S2 (C (1-1-1), C (1-1-
2)) from the intersection D2 (C (1-1-7), C (1-
1-8)) Perform a search.

The distance from the starting point to the connecting intersection D2 is compared with the distance from the destination to the connecting intersection D2. For example, the distance from the departure point and the distance from the destination , The connecting intersection is C (2-6-3) and C (1-1-1) whose distances are shorter from (22 + 3) <(21 + 2).
8) is the connection intersection D2 which is the shortest route.

Layer 1 route C (1-1-8) -C (1-1-
6) Take out -C (1-1-5) -C (1-1-2).

~ Load the work area of the departure block and route C (2-1-4) -C (2-1-
2) Take out -C (2-1-1).

~ Load the work area of the destination block, and route C (2-6-3) -C (2-6
Remove 2).

By synthesizing each of the above routes, C (2-1-1)
-C (2-1-2) -C (2-1-4) -C (1-1-
5) -C (1-1-6) -C (2-6-3) -C (2-
6-2) is output.

The above is the route search method. Next, an example of the help function will be described.

FIG. 20 is a diagram for explaining the flow of processing by the help function.

The help function operates by, for example, pressing a help switch. First, a help item is displayed, and a selection can be made from the help item. However, help operation cannot be performed during driving for safety. The following are prepared as examples of help items.

Entering the starting point To enter or change the starting point and depart from there.

Change destination When changing the destination to another destination on the route of the destination.

If you lose your way on the way to your destination and lose your current location without being able to return to that location.

Road closures If the road cannot be advanced due to road construction, etc. on the way to the destination.

Avoiding traffic congestion When you are involved in traffic congestion on the way to your destination, change your route to avoid it, and drive on another route.

Detours One way off the route on the way to the destination, and then returning to the place off the route again.

Description of Help Function Explanation of the above items The processing flow of the help function is as shown in FIG. 20. First, a help processing flag is turned on in a step, and then a normal operation state flag is
Normal operation work area data such as route data, current location information, departure location, initial departure location, and destination data are stored in nonvolatile RAM.
Evacuate to the area. Next, it is determined in a step whether or not the vehicle is currently traveling. If the vehicle is traveling, a message such as "Please stop the help operation after stopping the vehicle for safety." And the process of turning off the flag during the help process is performed (step), and the help operation ends.

However, if it is determined in the step that it is currently stopped, a menu screen of a help item is displayed in the step. Therefore, when any of the help items is input from the touch panel (step),
If it is not canceled, the processing of each help item is performed (step), and if it is canceled, the process returns to the step. If the help switch is pressed during the processing of each item, the process returns to the step and the step.

If a route display including travel history information is employed as needed in the help function, useful information for the user can be provided.

The conventional navigation device has a problem that, for example, when the vehicle accidentally deviates from the route at an intersection or the like, the vehicle cannot follow the guidance of the navigation device unless the vehicle returns to the set route again. In addition, whether or not the vehicle has passed a predetermined intersection according to the route guidance is based on the assumption that the travel distance, right turn, left turn, and the like are detected by a distance sensor and a steering angle sensor. However, there is also a problem that judgment errors are easily induced. For this reason, a device for guiding a route to a destination even when the route deviates from a set route has been proposed (JP-A-61-21610).

This means for detecting that the vehicle has departed from the planned traveling route, means for detecting an intersection on the planned traveling route to be returned from the current position, means for detecting the direction of the returning intersection with respect to the vehicle traveling direction, Means for displaying guidance information necessary for guiding the vehicle along the planned traveling route, and displaying information indicating the direction of the return intersection with respect to the vehicle traveling direction when the escape from the route is detected. is there. The route display method of the navigation device according to the present invention can be effectively used even in combination with the help function or the route guidance function.

It should be noted that the present invention is not limited to the above embodiment, and various modifications are possible. For example, in the embodiment described above, the route is displayed as the guide map after the route search. However, the route is not necessarily displayed in this step, and this route display may be used as one item of the help function. . Also, the route history is described as displaying the travel history in a color different from that of the route. However, only the current position may be displayed in a flash or another different display mode according to the travel history. Furthermore, the drawing map data was composed of 35 sheets of 4 divisions and 16 divisions,
Depending on the information density or the like of each area, a division size or a portion for preparing divided drawing map data may be selected, and an area having a low information density may be partially omitted.

As is clear from the above description, according to the present invention, as the route display map data, the upper layer basic drawing map data corresponding to the maximum drawing area and a plurality of lower layer hierarchies obtained by dividing the basic drawing map data into regions. Since the data has a hierarchical structure composed of the enlarged drawing map data of the area and the enlarged drawing map data of the lower hierarchy is used in the narrow area according to the route, it is possible to provide a display in which the route of the local portion is easily understood. In addition, since the map is drawn by selecting the basic drawing map data or the enlarged drawing map data in which the route falls within the drawing range from the set route, the optimum drawing map data for displaying the set route is selected. Just draw,
The amount of data processing can be reduced, and all routes can be displayed on a map without protruding from the screen. Therefore, it is possible to speed up the route display,
The route display can be appropriately performed in response to a user request. In addition, when there are a plurality of corresponding drawing map data, by selecting the drawing map data whose area is the narrowest and the path is located at the center from the center, it is possible to provide a route display which is always easy to see.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining an embodiment of a navigation device according to the present invention, FIG. 2 is a diagram showing a display example, FIG. 3 is a diagram showing an example of division of drawing map data, and FIG. FIG. 5 is a diagram showing an example of the structure of a display data management table, FIG. 6 is a diagram showing an example of the structure of road node column selection data, and FIG. 7 is a diagram of the drawing map selection data. FIG. 8 is a diagram showing an example of the structure of layer 1 and 2 road node data, FIG. 9 is a diagram showing an example of the structure of drawn map data, and FIG. 10 is a diagram showing one embodiment of a route search method. FIG. 11 is a diagram for explaining, FIG. 11 is a diagram showing an example of a data structure of a block a in the layer 32 of FIG. 10, FIG. 12 is a diagram showing an example of a data structure of a block d in the layer 32 of FIG. Fig. 13
FIG. 14 shows an example of the data structure of block f in layer 32 of FIG. 10, and FIG. 14 shows block a of layer 31 in FIG.
FIG. 15 is a diagram showing an example of a data structure of a work file and an index file, FIG. 16 is a diagram for explaining a flow of an entire process in a route search, and FIG.
The figure shows an example of the same block search routine, FIG. 18 shows an example of the adjacent block search routine, FIG. 19 shows an example of the remote block search routine, and FIG. 20 shows the flow of processing by the help function. FIG. 11 distance meter, 12 steering angle meter, 13 input unit, 14 input decoding unit, 15 input decoding table, 16 data processing control unit, 17 image output control unit, 18 ...... Display unit, 21 to 23
……File.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shoji Yokoyama 10 Takane, Fujii-cho, Anjo-shi, Aichi Prefecture Inside Aisin AW Co., Ltd. (56) References JP-A-63-271110 (JP, A) JP-A JP-A-61-75375 (JP, A) JP-A-61-166583 (JP, A) JP-A-2-140788 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G09B 29 / 10 G01C 21/00 G08G 1/0969

Claims (6)

(57) [Claims] 1. A navigation device for performing a route search from a designated departure point and a destination to set a route and provide route guidance, wherein a storage means for storing map data, and a map data stored in the storage means. Display means for displaying a map and the set route on the basis of, and area determining means for obtaining, as a drawing area of the map displayed on the display means, an area including the entire set route. The navigation device displays a map using the area determined by the area determination means as a drawing area, and superimposes and displays a route on a road on the map. 2. The storage means stores drawing map data having a hierarchical structure in which an area of an upper hierarchy is divided and expanded from an upper hierarchy to a lower hierarchy with a high degree of detail. 2. The navigation device according to claim 1, wherein the selected map data of the hierarchy of the area including the entire area is selected and displayed. 3. The drawing map data of the lower hierarchy is composed of drawing map data obtained by equally dividing a region of an upper hierarchy and drawing map data of the same size centered on the divided boundary region. 2. The navigation device according to 2. 4. When there are a plurality of hierarchical map data as hierarchical map data of an area including the entire set route, the display means selects the lowest hierarchical map data. 3. The navigation device according to claim 2, wherein: 5. The navigation apparatus according to claim 1, wherein said area determining means obtains a rectangular area defined by an end point on the route as an area including the entire set route. 6. The navigation apparatus according to claim 1, wherein the area determining means obtains an area including the entire route from the coordinate sequence of the set route.