JPH0816991A - Guiding route searching method - Google Patents

Abstract

PURPOSE:To search an optimum route to meet the usual driving tendency of a driver. CONSTITUTION:A traveling condition detecting and recording part 15 detects traveling speed classified by the kind and the width of a road on which a vehicle has traveled by using a vehicle position and time detected by a GPS receiver 2 and the map data of a CD-ROM 1, and records beforehand a histogram in a traveling condition memory 16. When the driver sets a route guidance mode, and designates a destination, a start place.destination setting part 18 sets a designated place as the destination and a present place as a start place. Subsequently, a driving tendency analyzing part 19 analyzes the degree of skill of the driver by using the recorded data of the traveling condition memory 16, and in the case of a skilled driver, an optimum route searching part 20 searches the optimum route in which the simple cumulative distance of distance between intersecting points is shortest, and in the case of an unskilled driver, it searches the optimum route in which the cumulative distance weighted in accordance with the width is shortest, and stores it in a guiding route memory 21. After this, a map picture drawing part 12 draws a map picture including the vehicle position together with a guiding route and a vehicle position mark, and displays them on a display device 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide route search method, and particularly when searching for an optimum route connecting a certain starting point to a certain destination with reference to map data, the route is adjusted according to the driving tendency of the driver. The present invention relates to a guide route search method for searching under different search conditions.

[0002]

2. Description of the Related Art A vehicle-mounted navigation device is a large-capacity storage device such as a CD-ROM for storing a large amount of map data.
A display device, a vehicle position detection device for detecting the current position of the vehicle, and the like are provided, and map data including the current position of the vehicle is read from the CD-ROM, and a map is drawn on the display screen based on the map data. The position mark (location cursor) is fixed at a fixed position on the display screen (for example, the center of the screen), the map is scrolled according to the movement of the vehicle, or the map is fixed on the screen.
The vehicle position mark is moved and displayed so that the user can easily recognize where the vehicle is currently traveling.

The map stored in the CD-ROM is divided into a longitude width and a latitude width of an appropriate size according to the scale level, and roads and the like are vertices (nodes) expressed in latitude and longitude.
, Which are represented by a coordinate set of, and these drawing is performed by connecting each node in order by a straight line. The road is composed of two or more nodes connected to each other, and a part connecting the two nodes is called a link. The map data includes (1) a road layer including a road list, a node table, an intersection constituent node list, and an intersection net list, (2) a background layer for displaying roads, buildings, rivers, etc. on the map screen,
(3) It is composed of a character layer for displaying the names of cities, towns and villages, road names, and the like.

Of these, the road layer has the structure shown in FIG. The road list RDLT is classified by road into road types (0; national roads, 1; expressways, 2; general roads, 3; other roads), the total number of nodes that make up the roads, and the node table NDTB of nodes that make up the roads. And the width to the next node (0; 1.5m to 2.5m, 1; 2.5m to 5.5m, 2; 5.5m to 11.0m, 3; 11.0m or more) Has been done. The intersection constituent node list CRLT is, for each intersection on the map, a set of positions on the node table NDTB of the other end node of the link (referred to as an intersection constituent node) which is connected to the intersection. The node table NDTB is a list of all nodes on the map. Position information (longitude, latitude) for each node, an intersection identification flag indicating whether or not the node is an intersection, and if the intersection is an intersection, the node configuration node list is displayed. It is composed of a pointer or the like that points to the position and points to the position of the road to which the node belongs on the road list if it is not an intersection.

The intersection netlist CRNL is (1) intersection sequential number for each intersection node (2) map leaf number of the map including the intersection node (3) data unit code Above, intersection node ID (4) intersection constituent node Number (5) Sequential number of each adjacent intersection (6) Distance to each adjacent intersection (7) Road attributes (road type, width) to each adjacent intersection.

[0006] By the way, in the car navigation system,
For example, there is a route guidance function that searches the optimum route from the starting point to the destination point and follows the shortest distance and displays the guidance route on the screen to guide the driver's travel. The driver can easily reach the destination by distinguishing it from other roads by displaying it in a specific color in bold, or by displaying a guide mark that moves along the guide route in front of the vehicle position mark. Is done.

A method called a horizontal search method has been proposed as a method for obtaining an optimum route from a starting point to a destination point. In this horizontal search method, the shortest route from the starting point to the destination is considered in consideration of all the intersections existing in a region having a radius connecting a straight line connecting the starting point and the destination, or in a region larger than the region, and the intersection netlist CRNL. It refers to and searches. FIG. 11 is a schematic explanatory diagram of the horizontal search method, in which a road is a straight line and intersections are graphed as intersections of straight lines. The distances between the intersections are known, STP is a departure point (intersection), and DSP is an objective. It is the ground (intersection).

In the horizontal search method, an intersection net list is used.
To CRNL, go to the intersection STP
Along the intersection A₁~ A_FourLook for each intersection A
₁~ A_FourTherefore, the corresponding intersection before this one (departure
Calculate the cumulative distance from the intersection)₁~ A_FourAgainst
Sequential number to identify the next intersection
Stored in memory together with the number. Then, at each intersection A₁~
A_FourIntersection B adjacent to each other along the road_ijLooking for
For each intersection, exit via the corresponding previous intersection
Calculate the cumulative distance from the departure point and find each intersection B_ijCorresponding to
With a sequential number that identifies the previous intersection
Store in memory. For example, at intersection A ₁For
Intersection B₁₁, B₁₂, B₁₃Find each of these intersections
Corresponding to, B₁₁: Intersection A₁Cumulative distance Bd from the place of departure via₁₁ B₁₂: Intersection A₁Cumulative distance Bd from the place of departure via₁₂ B₁₃: Intersection A₁Cumulative distance Bd from the place of departure via₁₃ .. (A) corresponds to intersection A₁With the sequential number of
Remember Also, at intersection A ₂For 3 intersections
B_{twenty one}, B_{twenty two}, B_{twenty three}Is obtained, and each intersection B_{twenty one}, B_{twenty two}, B _{twenty three}
Corresponding to, B_{twenty one}: Intersection A₂Cumulative distance Bd from the place of departure via_{twenty one} .. (B) B_{twenty two}: Intersection A₂Cumulative distance Bd from the place of departure via_{twenty two} B_{twenty three}: Intersection A₂Cumulative distance Bd from the place of departure via_{twenty three} The corresponding intersection A₂Memorize with. Other intersection A
₃, A_FourSimilarly, search for an adjacent intersection and
Data. By the way, at intersection B₁₃And B_{twenty one}Are the same
It is an intersection. Thus, the intersection where the data should be stored
Have already overlapped, and already accumulated on different routes for the intersection.
When distance data is stored, the cumulative distance from the point of departure
Separation Bd₁₃And Bd_{twenty one}Of the smaller data
Memorize only. For example, Bd₁₃> Bd_{twenty one}If so,
Difference point B₁₃(= B_{twenty one}) The cumulative distance shown in (B)
Separation Bd_{twenty one}Intersection A just before, which corresponds to₂The sequence of
The card number is finally stored.

Thereafter, in the same manner, each intersection B_ijabout
Adjacent intersection C_ijFor each intersection C _ijFor each
Obtain the cumulative distance from the departure point via the intersection just before
Therefore, with the sequential number of the intersection before this one
And refer to the intersection netlist.
For adjacent intersections, find the
From the departure point via the corresponding intersection before you
Calculate the cumulative distance and the sequential number of the intersection before you
If you memorize it together with the number, you will finally reach the destination (intersection)
Reach the DSP.

When the destination DSP is reached, the destination (m
The intersection before the one stored in association with the next intersection), the intersection before the one stored in association with the intersection, ... The shortest optimal route is the route that is sequentially connected to the side. As described above, the intersection netlist CRNL is stored in advance in the CD-ROM as a part of the road layer and is not stored in the CD-ROM. It may be created by using road layer information (road list RDLT, intersection configuration node list CRLT, node table NDTB, etc.), or the route search may be performed from the destination intersection to the departure intersection. Similarly, the optimum route can be obtained.

As described above, according to the horizontal search method, the optimum route is obtained by using the shortest distance as an index in graph theory. Therefore, the optimum route can be displayed together with the vehicle position mark in the map image on the screen, and the driver can be guided to the desired destination.

[0012]

However, in the above-mentioned conventional guide route search method, the optimum route with the shortest distance is simply searched without considering the width and type of the road. In this case, many narrow roads are included, and in this case, it may be difficult for a driver who is inexperienced to drive, and most of the optimal routes include highways and national roads. It was not included, and it was sometimes difficult for the driver, who is usually driving on these main roads, to drive differently. From the above, an object of the present invention is to provide a guide route search method capable of searching for an optimum route that matches a driver's usual driving tendency.

[0013]

According to the present invention, there is provided a means for detecting and recording one or a plurality of driving situations such as a type of a road on which a vehicle has traveled, a width of the road, and a traveling speed. A means for analyzing the driving tendency of the driver from the driving situation of the driver and an optimum route connecting a certain starting point to a certain destination are searched with reference to the map data, according to the analysis result of the driving tendency of the driver. And a means for searching an optimum route under the search conditions.

[0014]

According to the present invention, the type of road on which the vehicle travels,
One or more types of traveling conditions such as road width and traveling speed are detected and recorded, and when searching for an optimum route connecting a certain starting point to a certain destination by referring to map data, The driving tendency of the driver is analyzed from the driving condition, and the optimum route is searched under the search condition according to the analysis result. As a result, when the driver has a high level of driving skill and usually travels on narrow roads frequently or the traveling speed is high, it is crowded by simply searching for the shortest route regardless of the width or type of the road. The route can be guided by an optimal route that avoids the main road. Conversely, when the driving skill is low and the driver does not normally drive on a narrow road or the traveling speed is slow, a wide road or a main road By preferentially searching for the shortest route, the route can be guided by the optimum route that is easy to drive, and the route can be guided by the optimum route that matches the normal driving tendency of each driver.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Overall Configuration FIG. 1 is an overall configuration diagram of a vehicle-mounted navigation device embodying a guide route search method according to the present invention. In the figure, 1 is a CD-ROM that stores map data composed of a road layer, a background layer, a character layer, and the like, 2 is a GPS receiver that detects the vehicle position and vehicle direction by satellite navigation, and also detects the current time, 3 is an operation unit including a map scroll key, an enlargement / reduction key for changing the scale of the map, a route guidance mode setting key, a destination setting key, etc. 4 is a vehicle position mark showing a map image corresponding to the current position of the vehicle, It is a display device that displays together with a cursor mark, a guide route, and the like.

Reference numeral 10 denotes a navigation controller having a microcomputer configuration, which draws a map image together with a vehicle position mark, a cursor mark, etc. using the map data in the CD-ROM 1 and displays it on the display device 4, or while the vehicle is traveling. When driving conditions such as road width, type, running speed, etc. are detected and recorded, or when the route guidance mode is set, the driving tendency of the driver (here, driving skill level) is analyzed from the driving conditions. After the starting point and the destination are set, the optimum route connecting the starting point and the destination is searched by the horizontal search method using the map data of the CD-ROM 1 under the search condition that matches the analysis result of the driving tendency. After the search, a map image is drawn together with the vehicle position mark and the guide route using the map data and displayed on the screen.

Of the navigation controller 10, 1
1 is a buffer memory for storing map data read from the CD-ROM 1, 12 is a navigation mode,
Draw a map image with the vehicle position as the center with the north facing upward using the map data including the vehicle position and the vehicle position mark, and in the map scroll mode, the cursor position (longitude, Draw a map image with north facing upwards, centered on latitude, together with a cursor mark, and in route guidance mode (after route search is completed), map image with north facing upwards, centered on vehicle position, is the vehicle position mark. , A map image drawing unit that draws together with the guide route. Reference numeral 13 is a video RAM for storing the image drawn by the map image drawing unit 12, and 14 is a video R.
An image conversion unit that reads out an image stored in the AM 13, converts it into a predetermined image signal, and outputs it to the display device 4.

Reference numeral 15 denotes a running condition detecting / recording unit, which uses the road layer (see FIG. 10) in the map data and the vehicle position and time detected by the GPS receiver 2 while the vehicle is running. A certain distance L on the road of the same type and width
Each time the vehicle travels, the road type, width, and average traveling speed are detected, and the frequency of each detected type, width, and average traveling speed is recorded as a histogram. For example, L is 0.2km, type is national road, highway, general road, other road, width is 1.5m or more and less than 2.5m, 2.5m or more and less than 5.5m, 5.5m or more and less than 11.0m, 11.0 Above m, the average traveling speed is divided into 0 to less than 20km, 20km to less than 40km, 40km to less than 60km, 60km to less than 80km, 80km or more.
At an average speed of 70km on roads with a width of 5.5m or more and less than 11.0m
When traveling 0.2 km, type = national road, width = 5.5 m or more 11.0
Increase the frequency by less than m and average running speed = 60km or more and less than 80km by 1. When traveling on various national roads, a histogram showing the type = driving status of national roads is as shown in FIG. The same applies when driving on another type of road. The average traveling speed is obtained by dividing L by the time t which is the difference between the time when the traveling of the distance L is started and the time when the traveling is ended. Reference numeral 16 is a running condition memory that stores a histogram indicating a running condition.

Reference numeral 17 denotes a cursor position calculation unit, which is initially set in the map scroll mode (immediately after the route guidance mode setting key is pressed to set the route guidance mode, the navigation controller 10 automatically sets the map scroll mode). The vehicle position detected by the GPS receiver 2 is initially set as the cursor position, and thereafter, the cursor position that continuously changes from the initial setting position is calculated according to the operation of the map scroll key and is output to the map image drawing unit 12, A map image is scrolled by rewriting the map image in the video RAM 13 so that the cursor position is always at the center (in the map scroll mode, a cursor mark is drawn at the center of the map image by the map image drawing unit 12). ).

When the route setting mode is set and the cursor mark at the center of the screen is set to the destination by map scrolling and the destination setting key is pressed, the GPS receiver 2 detects it at that time. The starting point / destination setting unit 19 sets the existing vehicle position as the starting point and the cursor position as the destination, and 19 sets the starting point and the destination, and then the driving status stored in the driving status memory 16 It is a driving tendency analysis unit that analyzes driving tendency (here, skill level).

An example of the analysis method by the driving tendency analysis unit 19 will be briefly described. On a general road and other roads that have less traffic than national roads and highways, a driver with a high degree of driving skill has a narrow width. It runs on relatively high speeds on roads, and often runs on narrow lanes to avoid congestion. On the other hand, a driver with a low degree of skill rarely travels on a narrow road, and when traveling, the speed is often low. Therefore, the driving tendency analysis unit 19 calculates the distribution of traveling speed for each width including national roads, general roads, and other roads excluding highways, and, for example, the width
If the ratio of the total frequency under conditions of less than 5.5 m and traveling speed of 60 km or more is more than a certain standard value, it is judged that the driver is skilled in driving. Also, width less than 5.5 m, traveling speed 60
Even if the ratio of the frequency of more than km to the whole is less than a certain standard value, the distribution of the traveling frequency for each width of general roads and other roads is calculated. When the ratio of the traveling frequency to the whole is equal to or higher than a certain reference value, it is determined that the operator is skilled in driving. When it cannot be determined that the user is skilled in driving, it is determined that he is not yet skilled.

It should be noted that simply when all the widths of all road types are combined and the total frequency is more than a certain reference value under the condition that the traveling speed is 60km or more, or the width is less than 5.5m. It may be determined that the operator is skilled in driving when the ratio of the traveling frequency to the whole is a certain reference value or more.

After 20 is set to the route guidance mode,
After setting the starting point and the destination and analyzing the driving tendency,
An optimal route search unit that searches for the shortest optimal route connecting the departure point and the destination using the intersection netlist in the map data by the horizontal search method, and when it is determined that the driver is skilled in driving, In order not to leak the narrow escape route,
The route is searched while obtaining the total distance (simple total distance) using the distance between the adjacent intersections as it is. On the contrary, when it is judged that the driver is not skilled in driving, the total distance (width) The route is searched while obtaining the priority cumulative distance).
Reference numeral 21 is a guide route memory that stores, as guide route data, a node sequence that forms an optimum route connecting a starting point to a destination, 22 is an initial setting immediately after power-on, and a route guide mode setting operation is performed by the operation unit 3. Etc. is a mode setting unit for setting a predetermined mode.

The road layer included in the road layer map data has a data structure similar to that of FIG. 10, and includes a road list RDLT, an intersection node list CRLT, a node table NDTB, and an intersection net prepared for each intersection node. List CRNL
Etc. are included. However, intersection netlist CRN
L is configured as shown in FIG. 3, and in the fixed data area FDA, (1) intersection sequential number (information identifying the intersection) (2) map leaf number of the map including the intersection node (3) Data unit code Above, Intersection node ID (4) Number of intersection constituent nodes (5) Sequential number of each adjacent intersection (6) Distance to each adjacent intersection (7) Attribute of road to each adjacent intersection (road type, width), etc. have. Up to seven adjacent intersection data are stored in one intersection netlist. The road type data is represented by a numerical value of 0 to 3, where 0 is a national road, 1 is a highway, 2 is a general road, and 3 is another road. The width data is also represented by a numerical value of 0 to 3, 0; 1.5 m or more 2.
Less than 5m, 1; 2.5m or more and less than 5.5m, 2; 5.5m or more and less than 11.0m, 3; 11.0m or more.

Further, the intersection netlist CRNL has a rewriting data area RDA, and the total distance (simple total distance when the driver is skilled, weighted total distance when the driver is not skilled) at the time of route search. Further, the sequential number of the previous intersection (one less than the order) and the search order can be stored.

When finding the simple cumulative distance for a certain adjacent intersection, the optimum route searching unit 20 stores the simple cumulative total stored in the RDA of the intersection netlist CRNL related to the previous intersection corresponding to the adjacent intersection. The distance information of the adjacent intersection is added to the distance. When obtaining the weighted cumulative distance, the RDA of the intersection netlist CRNL related to the previous intersection corresponding to the adjacent intersection is calculated.
The weighted cumulative distance stored in is added to the weighted distance by multiplying the distance information of the adjacent intersection by a coefficient r according to the road width. In this embodiment, as an example, the correspondence between the road width and the coefficient is as follows. 1.5m or more and less than 2.5m (0) ・ ・ ・ r = 4 2.5m or more and less than 5.5m (1) ・ ・ ・ r = 2 5.5m or more and less than 11.0m (2) ・ ・ ・ r = 1 11.0m or more (3 ) R = 0.5 That is, when the driver is not skilled in driving, even if the driving distance is the same, if the width is wide, the traveling time is relatively short and the driving is relatively easy. The distance should be shorter than the actual distance, and conversely, if the width is narrow, the traveling time will be long and the driver will need to be careful in driving.

4 to 7 are flow charts showing the operation of the navigation controller 10, FIG. 8 is an explanatory view of a route search method, and FIG. 9 is an explanatory diagram of a guide route, which will be described below with reference to these figures. When the navigation processing power supply is turned on, the GPS receiver 2 periodically detects the vehicle position, the vehicle direction, and the current time by satellite navigation. On the other hand, after the power supply of the navigation controller 10 is turned on, the mode setting unit 22 initializes the navigation mode (step 101), the map image drawing unit 12 inputs the vehicle position data and the vehicle direction data from the GPS receiver 2, and C
The map data including the vehicle position is read from the D-ROM 1 to the buffer memory 11, the map image with the vehicle position as the center and the north facing upward is drawn in the video RAM 13 using the read map data, and the map image Draw a vehicle position mark with the vehicle azimuth direction facing the center. Video R
The image drawn on the AM 13 is read by the video conversion unit 14, converted into a predetermined video signal, output to the display device 4, and displayed on the screen. As the vehicle moves, the map image drawing unit 12 redraws a new map image centered on the vehicle position in the video RAM 13 together with the vehicle position mark. As a result, the map image on the screen remains centered on the vehicle position mark. Scroll according to the movement of the vehicle (the above is the navigation process of step 102).

The running condition detecting and recording process other hand, during traveling of the traveling condition detection and recording unit 15 a vehicle, especially a road layer in the map data (see FIG. 10), the vehicle position and time detected by the GPS receiver 2 Each time the vehicle travels a road of the same type and width by a fixed distance L, the type of the road, the width, and the average traveling speed are detected, and the frequency of the detected type, width, and average traveling speed is converted into a histogram. And records it in the driving situation memory 16 (step 103, see FIG. 2).

Departure / destination setting processing, driving tendency analysis processing
Management Then, the driver when you want to travel in response to the route guidance from the current position to a certain destination, pressing the route guidance mode setting key. Then, the navigation controller 10 sets the route guidance mode, and first automatically sets the map scroll mode so that the driver can set the destination (steps 104 to 106). In the map scroll mode, the cursor position calculation unit 17 initializes the vehicle position at that time as the cursor position, and the map image drawing unit 12 sets the map image centered on the cursor position in the video R.
Draw on AM13 and draw a cursor mark at the center.

In this state, when the driver operates the map scroll key to search for a destination on the map image, the cursor position calculation unit 17 calculates the continuously changing cursor position, and the map image drawing unit 12 moves the cursor. Redraw the map image centered on the position with the cursor mark. Video R
The image drawn on the AM 13 is read by the video conversion unit 14, converted into a predetermined video signal, output to the display device 4, and displayed on the screen. As a result, the map image on the screen is scrolled according to the map scroll operation with the cursor mark at the center (above, the map scroll processing in step 107).

When the destination setting key is pressed when the cursor mark reaches the desired destination, the starting point / destination setting section 18 sets the vehicle position detected by the GPS receiver 2 at that time to the starting point, The cursor position is set as the destination (steps 108 and 109). Subsequently, the driving tendency analysis unit 19 analyzes the skill level of the driver from the driving situation stored in the driving situation memory 16 and notifies the optimum route searching unit 20 of the analysis result (step 110). After the analysis of the driver's skill level is completed, the optimum route search unit 20 searches for the shortest optimum route connecting the departure place and the destination under the search condition according to the skill level by the horizontal search method. When the skill level is high, the search is performed by simply calculating the cumulative total distance obtained by simply accumulating the distances between the adjacent intersections, and when the skill level is low, the weighted cumulative distance is obtained by weighting the distance between the adjacent intersections according to the width. While exploring.

Route Search Process (When Driver is Skilled) First, the optimum route search process when the degree of skill is high will be described. Here, for simplification, it is assumed that the intersection netlist CRNL of any intersection includes the first to fourth adjacent intersections, and the lower adjacent in FIG. 8 is the first adjacent intersection and the right adjacent is It is assumed that the second adjacent intersection, the upper adjacent one is the third adjacent intersection, and the left adjacent one is the fourth adjacent intersection.

First, the optimum route searching unit 20 checks whether or not the departure place is an intersection (step 201 in FIG. 5), and if it is an intersection, the departure place intersection STP is set (step 202). If not, the nearest intersection is set as the departure point intersection STP (step 20).
3), the processing after step 204 is performed. When the departure point intersection STP is determined, the optimum route search unit 20 checks whether the destination is an intersection (step 204), and if it is an intersection, the destination intersection DSP is set (step 205), step 2
If it is not an intersection, the nearest intersection is set as the destination intersection DSP (step 206), and the processing from step 207 is performed.

Departure intersection STP and destination intersection DS
When P is determined, the optimum route searching unit 20 firstly intersects all the intersections included in a circle centered on the departure point intersection STP and having a radius slightly longer than the distance between the departure point intersection STP and the destination intersection DSP. CD netlist CRNL
-Reading from the map data in the ROM 1, the storage unit 20-1
(Step 207). Then, the search order i is set to 0 (step 208). Up to this point, it is commonly performed regardless of the level of skill. When the driver is an expert driving person (YES in step 209), the storage unit 20-
By referring to the intersection net list CRNL related to the i-th intersection stored in No. 1, it is checked whether or not an intersection adjacent to the i-th intersection remains (step 210). The 0th intersection is the starting point intersection STP. Note that step 210
By then, the j-th intersection (j = 0, 1, ...
Items that are marked i) are excluded.

Here, since four adjacent intersections remain, the first adjacent intersection A ₁ from the starting intersection STP to the first adjacent intersection A _{1 in the} intersection net list CRNL related to the starting intersection STP. The simple cumulative distance D from the starting point intersection STP to the adjacent intersection A ₁ is calculated with reference to the distance d ₂ of (step 211). D
Is given by the following equation d ₁ + d ₂ → D, where d ₁ is the simple cumulative distance from the departure point intersection STP to the i-th intersection. Initially, when i = 0, d ₁ = 0, so D =
It becomes d ₂ .

Next, by referring to the rewriting data area RDA of the intersection netlist CRNL related to the intersection A ₁ stored in the storage unit 20-1, whether the search order of the adjacent intersection A ₁ is (i + 1), Then, for the intersection A ₁ , it is checked whether or not the information for specifying the simple cumulative distance on the different route and the previous intersection is already registered (step 212), and it is NO here, so that the adjacent intersection A _{1 is} concerned. In the intersection netlist CRNL related to the intersection A ₁ , (a) the sequential number of the 0th-order intersection STP currently being focused on, (b) the departure intersection STP to the adjacent intersection A ₁ simple total distance D (= Ad _1), stored in the rewrite data area RDA and write (i + 1) = 1 as (c) search order of the adjacent intersection a ₁ Stored in the image data area RDA (step 213).

Then, returning to step 210, referring to the intersection netlist CRNL for the starting point intersection STP, it is checked whether or not the intersection adjacent to the 0th intersection of interest still remains. The process of is repeated. As a result, since the adjacent intersections A _{1 to} A ₄ are present in the intersection netlist of the departure intersection STP, these are regarded as primary intersections, and each data of the intersection netlist CRNL relating to these primary intersections is rewritten. In the area, simple cumulative distances Ad _{1 to} Ad ₄ and each adjacent intersection A ₁
Sequential number is registered to identify one before the intersection STP corresponding to to A _4.

When the processing is completed for all the adjacent intersections included in the intersection net list CRNL for the departure point intersection STP, the optimum route searching unit 20 determines whether there is a 0th intersection other than the departure point intersection STP. However, since it does not exist (step 210 in FIG. 5, step 301 in FIG. 6), it has reached the destination intersection DSP in other words, or in other words, the destination intersection DS in the (i + 1) th intersection.
It is determined whether P is included (step 302), and if not, i is incremented to 1 (step 3).
03). Then, the process proceeds to step 210 of FIG. 5, and attention is paid to one of the primary intersections, A ₁ , and the storage unit 20-
Intersection netlist C related to intersection A ₁ stored in ₁
With reference to the RNL, it is determined whether or not the adjacent intersections remain except the 0th-order intersection STP.

Here, B₁₁, B₁₂, B₁₄There exists
So, first of all, the first adjacent intersection B ₁₁About the intersection
A₁Please refer to the intersection netlist CRNL related to
From departure point intersection STP to adjacent intersection B₁₁Up to simple
The cumulative distance D is calculated (step 211). Departure crossing
From the point STP, the first intersection A that is currently focused on₁For up to
Simple total distance d₁In the storage unit 20-1 at intersection A₁In charge
Ad to RDA of intersection netlist CRNL₁As
It is memorized and the first intersection A₁From the adjacent intersection
B₁₁Distance to₂Is intersection A₁Intersection related to
Since it is stored in the strike CRNL, Ad₁+ D₂→ From D to the first intersection A from the intersection STP₁Via
Said adjacent intersection B₁₁The simple cumulative distance D to
It

Next, referring to the rewriting data area RDA of the intersection netlist CRNL related to the adjacent intersection B ₁₁ stored in the storage unit 20-1, it is checked whether the search order of the adjacent intersection B ₁₁ is (i + 1) (step 212), which is NO here, so that the intersection netlist C relating to the intersection B ₁₁ is made to correspond to the adjacent intersection B _11.
In the RNL, (a) The first intersection A that is currently focused on
₁ sequential number, (b) simple cumulative distance D (= B from the starting point intersection STP to the adjacent intersection B ₁₁ )
d ₁ ), is stored in the rewrite data area RDA, and (c)
(I + 1) = 2 as the search order of the adjacent intersection B ₁₁
Is stored in the rewrite data area RDA (step 21).
3). Then, the process returns to step 210 and the intersection netlist CRNL related to the primary intersection A ₁ stored in the storage unit 20-1 is referenced to refer to the primary intersection A currently being focused on.
Check whether the intersection adjacent to ₁ still remains, and if it does, repeat the same process.

When returning to step 210, the optimum route searching section 20 determines YES because the adjacent intersections B ₁₂ and B ₁₄ are present. Then, of these, for the second adjacent intersection B ₁₂ , after calculating the simple cumulative distance D from the departure point intersection STP to the adjacent intersection B ₁₂ (step 211), the adjacent intersection B ₁₂ stored in the storage unit 20-1. The data rewriting area RDA of the intersection netlist CRNL corresponding to is checked to see if the search order is already 2 (step 212).
The sequential number of the first intersection A ₁ , the simple cumulative distance D = Bd ₁₂ , and the search order 2 are registered in A (step 21).
3). Then, returning to step 210, the remaining adjacent intersections B ₁₄ stored in the intersection net list CRNL of the intersection A ₁ are processed in the same manner as described above.

B₁₄When the processing of
The search unit 20 checks whether there is another primary intersection.
(Step 301 in FIG. 6), A here₂,
A₃, A _FourExists, then A₂A new primary
As an intersection, the processing after step 210 of FIG. 5 is performed.
(Step 304).

Intersection netlist CRNL of intersection A ₂
There are first to fourth adjacent intersections B _{21 to} B ₂₄ in
B ₂₄ = Starting point intersection STP, so the fourth adjacent intersection B ₂₄
Are removed and processed in step 210. And first B
_{For 21} , the optimum route search unit 20 refers to the intersection netlist CRNL of the intersection A ₂ and refers to the departure point intersection ST.
Adjacent intersection B ₂₁ from P via the first adjacent intersection A ₂
To calculate the simple cumulative distance D (steps 210, 2)
11).

Then, the optimum route searching unit 20 is connected to the storage unit 2.
It is checked whether the degree of the adjacent intersection B ₂₁ is 2 by referring to the intersection netlist CRNL of the adjacent intersection B ₂₁ stored in 0-1 (step 212), but B ₂₁ = B ₁₂ and the adjacent intersection B ₁₂ of the adjacent intersection B ₁₂ is checked. Since the order is already 2, the result is YES. This indicates that the intersection B ₁₂ adjacent to the primary intersection A ₁ has already been processed (the data of the above (a) to (c) has been stored), but in this case, first, the adjacent intersection The departure point intersection STP stored in the rewriting data area RDA of the intersection netlist CRNL relating to B _12.
Simple total distance from * D = Bd ₁₂ and this time step 211
The magnitude of the distance D obtained in step S1 is compared (step 214).

If D << D, the adjacent intersection B
The sequential number of the i-th intersection A ₁ stored in the rewriting data area RDA of the intersection netlist CRNL of ₁₂ (= B ₂₁ ) is the i-th intersection A ₂ currently focused on.
And the simple cumulative distance * D is rewritten with D = Bd ₂₁ (step 21).
5). If D ≧ * D, RDA is not rewritten. Then, the process returns to step 210 and the same process is performed for the next adjacent intersection related to the first intersection A ₂ .

Thereafter, the same processing is sequentially repeated,
In the check in step 302 in FIG. 6, the (i +
1) Destination intersection DSP among all the following intersections
When it is determined to be YES, the rewriting data area R is first stored in the intersection netlist CRNL related to the destination intersection DSP stored in the storage unit 20-1.
The previous (m-1) th intersection corresponding to the destination intersection DSP (m-th intersection) stored in the DA, and the intersection netlist CRNL relating to the (m-1) th intersection Among them, the previous (m−2) th intersection corresponding to the intersection stored in the rewriting data area RDA, ... The intersection netlist C relating to the secondary intersection
In the RNL, the primary intersection and the departure point intersection STP stored in the rewrite data area RDA are connected in reverse order to determine the shortest optimum route as seen from the simple cumulative distance, and the departure point intersection STP to the destination intersection point are determined. Guide route memory 2 using the node sequence forming the optimum route to the DSP as guide route data
It is stored in 0 (step 305).

As a result, when it is analyzed that the driver's driving skill is high, the optimum route is automatically searched under the search condition of the simple cumulative distance. It is possible to obtain the guide route data including the roads.

Route search processing (when the driver is not an expert
In contrast to this, when the driving tendency is analyzed and it is determined that the driver's skill level is not high (step 209 in FIG. 5).
No), the optimum route is searched under the condition that the width-first cumulative distance weighted according to the width is the shortest (see FIG. 7). That is, by referring to the intersection net list CRNL related to the i-th intersection stored in the storage unit 20-1, it is checked whether or not an intersection adjacent to the i-th intersection remains (step 401 in FIG. 7). 0th intersection is the starting point intersection ST
P. In step 401, the j-th
Excludes intersections (j = 0, 1, ..., i).

Since four adjacent intersections remain, the first adjacent intersection A ₁ from the starting intersection STP to the first adjacent intersection A _{1 in the} intersection netlist CRNL related to the starting intersection STP is left. The distance d ₂ ,
With reference to the road width, the width-first cumulative distance D ′ weighted according to the road width between the departure point intersection STP and the adjacent intersection A ₁ is calculated (step 402). D ′ is obtained by the following equation d ₁ ′ + r · d ₂ → D ′, where d ₁ ′ is the width-first cumulative distance from the departure point intersection STP to the i-th intersection. At first, when i = 0, d ₁ ′ = 0, so D
′ = R · d ₂ . r is the road width from the starting point intersection STP to the adjacent intersection A ₁ is 1.5 m or more and less than 2.5 m (0)
When r = 4, 2.5m or more and less than 5.5m (1) r = 2,
When 5.5m or more and less than 11.0m (2), r = 1, and when 11.0m or more (3), r = 0.5.

Next, referring to the rewriting data area RDA of the intersection netlist CRNL related to the intersection A ₁ stored in the storage unit 20-1, whether the search order of the adjacent intersection A ₁ is (i + 1), if, already per intersection a _1, the width preferences total distance and 1 in different routes
It is checked whether or not the information specifying the previous intersection has been registered (step 403), and since it is NO here, it is made to correspond to the adjacent intersection A ₁ and is stored in the intersection netlist CRNL related to the intersection A _1. , (A) Sequential number of the 0th intersection STP currently being focused on,
(B) The width-first cumulative distance D ′ (= Ad ₁ ′) from the departure point intersection STP to the adjacent intersection A ₁ is stored in the rewriting data area RDA, and (c) the search order of the adjacent intersection A ₁ is stored. (I + 1) = 1 is stored in the rewrite data area RDA (step 404).

Then, returning to step 401, referring to the intersection net list CRNL for the departure point intersection STP, it is checked whether the intersection adjacent to the 0th intersection of interest still remains. The process of is repeated. As a result, since the adjacent intersections A _{1 to} A ₄ are present in the intersection netlist of the departure intersection STP, these are regarded as primary intersections, and each data of the intersection netlist CRNL relating to these primary intersections is rewritten. 1 corresponds to the width-first cumulative distances Ad ₁ ′ to Ad ₄ ′ in the area
A sequential number that identifies the intersection STP just before is registered.

When the processing is completed for all the adjacent intersections included in the intersection net list CRNL for the departure point intersection STP, the optimum route searching unit 20 determines whether there is a 0th intersection other than the departure point intersection STP. However, since it does not exist (steps 401 and 405), it is determined whether or not the destination intersection DSP has been reached subsequently, in other words, the destination intersection DSP is included in the (i + 1) th intersection (step 406). ), If not, i is incremented to 1 (step 407). Then, in step 401, one of the first intersections A ₁
Paying attention to, the intersection net list CRNL related to the intersection A ₁ stored in the storage unit 20-1 is referred to, and it is determined whether or not the adjacent intersections remain except the 0th-order intersection STP.

Here, B₁₁, B₁₂, B₁₄There exists
So, first of all, the first adjacent intersection B ₁₁About the intersection
A₁Please refer to the intersection netlist CRNL related to
From departure point intersection STP to adjacent intersection B₁₁Width up to
The priority cumulative distance D'is calculated (step 402). Departure
From the ground intersection STP, the first intersection A that is currently focused on₁
Width priority cumulative distance up to₁'Is stored in the storage unit 20-1.
Difference point A₁RDA of intersection netlist CRNL related to
Ad₁It is stored as ´ and the first intersection A ₁From
The adjacent intersection B₁₁Distance to₂Is intersection A₁Pertaining to
Since it is stored in the intersection netlist CRNL, Ad₁′ + R · d₂→ From D'the departure intersection STP to the first intersection A₁Via
Said adjacent intersection B₁₁Width priority cumulative distance to
I want it.

Next, referring to the rewriting data area RDA of the intersection netlist CRNL related to the adjacent intersection B ₁₁ stored in the storage unit 20-1, it is checked whether the search order of the adjacent intersection B ₁₁ is (i + 1) (step 403), since it is NO here, the intersection netlist C relating to the intersection B ₁₁ is made to correspond to the adjacent intersection B _11.
In the RNL, (a) The first intersection A that is currently focused on
₁ sequential number, (b) Width priority accumulated distance D '(= from the departure point intersection STP to the adjacent intersection B ₁₁
Bd ₁ ′) is stored in the rewrite data area RDA,
(C) (i +) as the search order of the adjacent intersection B ₁₁
1) = 2 is stored in the rewrite data area RDA (step 404). Then, the process returns to step 401, and the storage unit 2
By referring to the intersection netlist CRNL related to the first-order intersection A ₁ stored in 0-1, it is checked whether or not the intersection adjacent to the currently-selected first-order intersection A ₁ still remains. The process of is repeated.

When the optimum route searching unit 20 returns to step 401, it determines YES because the adjacent intersections B ₁₂ and B ₁₄ are present. Then, of these, for the second adjacent intersection B ₁₂ , after calculating the width-first cumulative distance D ′ from the departure point intersection STP to the adjacent intersection B ₁₂ (step 402),
Data rewriting area RD of the intersection netlist CRNL corresponding to the adjacent intersection B ₁₂ stored in the storage unit 20-1
It is checked whether the search order is already 2 by referring to A (step 403), and since it is NO, the sequential number of the first intersection A ₁ and the width priority cumulative distance D ′ = Bd ₁₂ ′ in the data rewriting area RDA, The search order = 2 is registered (step 404). Then, returning to step 401, the remaining adjacent intersections B ₁₄ stored in the intersection net list CRNL of the intersection A ₁ are processed in the same manner as described above.

When the processing for B ₁₄ is completed, the optimum route searching unit 20 checks whether there is another first-order intersection (step 405), and here A ₂ , A ₃ , A ₄ is still present.
Is present, the process subsequent to step 401 is performed using A ₂ as a new first intersection (step 40).
8).

Intersection netlist CRNL of intersection A ₂
There are first to fourth adjacent intersections B _{21 to} B ₂₄ in
B ₂₄ = Starting point intersection STP, so the fourth adjacent intersection B ₂₄
Is removed and processed in step 401. And first B
_{For 21} , the optimum route search unit 20 refers to the intersection netlist CRNL of the intersection A ₂ and refers to the departure point intersection ST.
Adjacent intersection B ₂₁ from P via the first adjacent intersection A ₂
To calculate the breadth-first cumulative distance D '(step 40
2).

Then, the optimum route searching section 20 is connected to the storage section 2.
Although the degree of the adjacent intersection B ₂₁ is checked by referring to the intersection netlist CRNL of the adjacent intersection B ₂₁ stored in 0-1 (step 403), B ₂₁ = B ₁₂ and the adjacent intersection B ₁₂ of the adjacent intersection B ₁₂ is checked. Since the order is already 2, the result is YES. This indicates that the intersection B ₁₂ adjacent to the primary intersection A ₁ has already been processed (the data of the above (a) to (c) has been stored), but in this case, first, the adjacent intersection The departure point intersection STP stored in the rewriting data area RDA of the intersection netlist CRNL relating to B _12.
Width priority total distance from * D'= compares the magnitude of the distance D'obtained in Bd ₁₂ 'between the current step 402 (step 409).

If D '<<D', the adjacent intersection B
The sequential number of the i-th intersection A ₁ stored in the rewriting data area RDA of the intersection netlist CRNL of ₁₂ (= B ₂₁ ) is the i-th intersection A ₂ currently focused on.
Together replaced by the sequential number and rewrites the width preferences total distance * D'D'= at Bd ₂₁ '(step 410). If D ′ ≧ * D ′, RDA is not rewritten. After completing these processes, step 4 in FIG.
Returning to 01, the same process is performed for the next adjacent intersection related to the first intersection A ₂ .

Thereafter, the same processing is sequentially repeated,
In the check in step 406 of FIG. 7, the (i +
1) Destination intersection DSP among all the following intersections
When it is determined to be YES, the rewriting data area R is first stored in the intersection netlist CRNL related to the destination intersection DSP stored in the storage unit 20-1.
The previous (m-1) th intersection corresponding to the destination intersection DSP (m-th intersection) stored in the DA, and the intersection netlist CRNL relating to the (m-1) th intersection Among them, the previous (m−2) th intersection corresponding to the intersection stored in the rewriting data area RDA, ... The intersection netlist C relating to the secondary intersection
In the RNL, the primary intersection and the departure point intersection STP stored in the rewrite data area RDA are connected in reverse order to determine the shortest optimum route in terms of the width-first cumulative distance, and the departure point intersection STP is used to determine the destination. The node sequence forming the optimum route to the intersection DSP is stored in the guide route memory 21 as the guide route data with the width priority, and the route search process is completed (step 411).

As a result, when it is analyzed that the driver's driving skill is not high, the optimum route is automatically searched under the search condition of the width priority, so that the narrow road is avoided as much as possible. It is possible to obtain guide route data composed of roads that are easy for beginners to drive. Note that, here, for the sake of simplicity, the number of adjacent intersections at each intersection has been described as 4. However, even if there are various numbers at each intersection,
A simple guide route or a breadth-first guide route is required. In addition, the route search by the horizontal search method is performed at the destination intersection DSP.
It is also possible to perform the same process as described above, with 0 as the 0th-order intersection, and until reaching the starting point intersection STP. In this case, the departure point intersection, the previous intersection stored in association with the departure intersection, the previous intersection stored in association with the intersection, ... Connect in order to determine the optimum route.

Route guidance When the search for the optimum route according to the driving tendency of the driver is completed as described above, the map image drawing unit 12 causes the GPS receiver 2 to operate.
Vehicle position data and vehicle azimuth data are input, the map data including the vehicle position is read from the CD-ROM 1, and a map image with the vehicle position as the center and the north facing upward is drawn in the video RAM 13. In addition, from the guide route data stored in the guide route memory 21, a portion that is included in the area drawn in the video RAM 13 is selected, and the video RAM 13 is selected.
After drawing the guide route in 13 with a certain color thickly emphasized,
A vehicle position mark with the vehicle azimuth direction oriented is drawn at the center of the video RAM 13. The image in the video RAM 13 is read by the video conversion unit 14, converted into a predetermined video signal, output to the display device 4, and displayed on the screen. As the vehicle moves, the map image drawing unit 12 redraws a new map image centered on the vehicle position and the emphasis guidance route in the video RAM 13 together with the vehicle position mark. As a result, the map image on the screen is displayed together with the emphasis guidance route. With the vehicle position mark as the center, the scroll is performed in accordance with the movement of the vehicle (the above is the route guidance process in step 306 of FIG. 6).

If the driver is not an expert, the screen shown in FIG.
As shown in A of No. 1, since the guide route including many wide roads is displayed, it is possible to travel to the destination relatively easily, and if the driver is an expert, the guide route including the narrow road is displayed. Therefore, it is possible to reach the destination promptly while avoiding the congested road. During route guidance, the mode setting unit 22 compares the vehicle position with the destination data in the route guidance memory 21, and if they match, returns to the normal navigation mode (steps 307 and 308 in FIG. 6).

In the above-described embodiment, the skill level is analyzed as the driving tendency, the optimum route which is the shortest of the simple cumulative distance is searched when the skill level is high, and the cumulative distance weighted by the width when the skill level is not high. However, unlike this, we analyze which type of road is driving well as the driving tendency, and calculate the total distance weighted according to the ratio of the road type that has been driven in the past. The shortest optimum route may be searched. Specifically, when the traveling frequency of each road type was obtained from the histogram stored in the traveling situation memory, the national road was a ₀ , the expressway was a ₁ , the general road was a ₂ , and the other roads were a ₃ . Then, an intersection CR ₁ and an intersection C adjacent thereto
Road type up to R ₂ is q (q = 0; national road, q = 1; highway, q = 2; general road, q = 3; other roads), distance is d, a = a ₀ + a ₁ + a ₂ When + a ₃ , CR ₁ −
The distance between CR ₂ is weighted as L = {1- (a _q / a)} · d to obtain the total distance, and the driver normally searches for the shortest optimum route of the total distance. , It is possible to drive to a destination on a road that includes many types of roads that are running well.

For example, when many highways are usually used and a ₁ is large, if CR ₁ -CR ₂ is an intersection on the highway, the distance L between them is treated small, so the optimum route is high speed. Since many roads are included, you can reach your destination quickly and easily. On the contrary, normally,
When a lot of general roads are used and a ₂ is large, CR
If ₁ -CR ₂ is an intersection on a general road, the distance therebetween L is handled less, will be general road is contained much in the optimal path, to reach the destination without paying tolls You can

It is also possible to analyze which width of the road the vehicle is traveling on as a driving tendency, and to search for the optimum route having the shortest cumulative distance weighted according to the ratio of the types of roads traveled in the past. Specifically, when the traveling frequency for each width is calculated from the histogram stored in the traveling condition memory, b ₀ is 1.5 m or more and less than 2.5 m, b ₁ is 2.5 m or more and less than 5.5 m, and b _{1 is} 5.5 m or more and less than 11 m. When b ₂ and 11 m or more become b ₃ , the road width from a certain intersection CR ₁ to a certain intersection CR ₂ is r (r = 0; 1.5 m or more and less than 2.5 m, r = 1;
2.5m or more and less than 5.5m, r = 2; 5.5m or more and less than 11m, r =
3; or 11m), when the distance is d, the distance L between the _{CR 1 -CR 2, L = {} 1- (b r / b)} · d and while seeking total distance weighting, the該累meter distance By searching for the shortest optimum route, the driver can drive to the destination on a road that includes many road widths that are normally well traveled.

For example, when many roads with a wide width are usually used and b ₃ is large, if the road between CR ₁ and CR ₂ is r = 3, the distance L between them is treated as small.
Since the optimal route includes many roads with a wide width, it is possible to reach the destination with easy driving. vice versa,
Usually, many roads with narrow width are used, and when b ₁ is large and the road between CR ₁ and CR ₂ is r = 1, the distance L between them is treated as small, so the optimum route has width Many narrow roads will be included, and you can reach your destination through a loophole.

[0068]

As described above, according to the present invention, one or more types of traveling conditions such as the type of road on which the vehicle has traveled, the width of the road, the traveling speed, etc. are detected and recorded, and are recorded from a certain departure place. When searching for the optimal route connecting to the destination with reference to the map data, the driver's driving tendency is analyzed from the past driving situation, and the optimal route is searched under the search condition according to the analysis result. Therefore, if you are highly skilled in driving and you are often driving on narrow roads or traveling at high speeds, you can simply search for the shortest route regardless of the width and type of the road, and it will become crowded. The route can be guided by an optimal route that avoids the main road. Conversely, when the driving skill is low and the driver does not normally drive on a narrow road or the traveling speed is slow, a wide road or a main road Prioritize the shortest By searching for a road, the travel easily optimum route or the like can be route guidance, it is possible to perform route guidance with the optimal route to match the usual driving style of the respective driver.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a vehicle-mounted navigation device that embodies a guide route search method according to the present invention.

FIG. 2 is an explanatory diagram of a histogram stored in a traveling condition memory.

FIG. 3 is an explanatory diagram of an intersection netlist.

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

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

FIG. 6 is a third view showing the operation of the navigation controller.
2 is a flowchart of.

FIG. 7: Fourth showing the operation of the navigation controller
2 is a flowchart of.

FIG. 8 is an explanatory diagram of route search.

FIG. 9 is an explanatory diagram of a guide route.

FIG. 10 is an explanatory diagram showing a data structure of a road layer.

FIG. 11 is an explanatory diagram of a horizontal search method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CD-ROM 2 GPS receiver 3 Operation part 4 Display device 10 Navigation controller 12 Map image drawing part 13 Video RAM 14 Video conversion part 15 Running condition detection / recording part 16 Running condition memory 19 Movement tendency analysis part 20 Optimal route searching part 21 Guided path memory

Claims (1)

[Claims] 1. An optimum route connecting a certain starting point to a certain destination by detecting and recording one or more kinds of driving conditions such as the width of the road on which the vehicle has traveled, the type of the road, and the traveling speed. When referring to map data for search, the driver's driving tendency is analyzed from the past driving situation, and the optimum route is searched under the search conditions according to the analysis result. Search method.