JPH08292058A - Route searching device - Google Patents

Abstract

PURPOSE: To calculate a separate route with a sufficient difference to the last route result with certainty by referring to the last route searching result at an interval between the same departure and destination, and using a means taking a correspondence with route searching data at present. CONSTITUTION: A route searching means 5 reads route searching data out of a map data storage means 2 and then it compares that whether the same road link with the last route searching result stored by a route control means 7 or not through a link cost renewal part 52. If there is the same link nor, the moving cost of a road link in the route searching data 22 is renewed, and the route searching data renewed in the link cost are processed by a route calculating part 51, whereby a separate route is made selectable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route search device such as a vehicle-mounted navigation device and a vehicle locator device for installing a base station.

[0002]

2. Description of the Related Art Currently, many navigation devices have an automatic route setting function, and there are a plurality of routes depending on the route calculation conditions such as distance priority and travel time priority, or toll road priority or toll road non-priority. The demand for is realized.

FIG. 16 is a block diagram showing a configuration example of a route search device in a conventional navigation device. In FIG. 16, 1 is a position detecting means for detecting the current position of the vehicle,
2 is a map data storage means, which comprises two parts 21,
Composed of 22. Reference numeral 21 is road information / geographical information recording the shape / connection relationship of roads and the positions / names of peripheral facilities, and 22 is route search data recording a road network for route search. 3 is an input means for setting a point or starting a route search, 4 is a starting point set from the current position of the position detection means 1, and the road information / geographic information and index of the map data storage means 2 by the input means 3 Point setting means for setting a destination by operating information, 5 is a route searching means for calculating the shortest route connecting a starting point to a destination at a minimum cost, 6 is position information of the position detecting means 1, and map data storage It is a display means for presenting and displaying the road information / geographic information of the means 2 and the route information by the route searching means 5.

An outline of the operation of the route search device in the navigation device will be described. The point setting means 4 sets the departure point by associating the information of the current position by the position detecting means 1 with the road links and nodes of the route search data 22, and sets the departure point on the road information / geographic information 21 designated by the input means 3. The destination is set by associating the position information of the above with the route search data 22.

The route searching means 5 searches for a road link in the peripheral area of the searched area centering on the starting point by a calculation method such as the Dijkstra method, and then determines the travel cost of the road link to the arrival cost of the outer edge of the searched area. The search range is expanded while adding, and the shortest route from the starting point to the destination is created when the destination is included in the search range.

At this time, in the conventional search, the route search data 22 shown in FIG. 2 is provided with the node table 22a and the road link table 22b in which the road type and the cost for each search condition are recorded. Depending on the type of cost to be used, or the unit of cost is changed according to the type of road, the route of the condition that meets the user's request is calculated.

[0007]

However, the above-described conventional route search device has a problem that only one route can be calculated in the route calculation between the same search condition and the same point. For example, if the route result presented to the request for route calculation on the condition that the toll road is not used does not satisfy the user, the conventional route search device will no longer calculate an alternative route under the same search condition. Can not.

Further, when the number of links in the road network is small or when the cost of the road links for each search condition is small, there may be a case where the difference hardly appears despite the route results under the different search conditions. , There was not enough choice for the type of route presented to the user.

The present invention solves such a conventional problem, and every time the route calculation is repeated under the same search condition and the same point, the route result is stored in a storage device and a new route search is performed. In order to provide a route search device capable of presenting a plurality of different routes that make the best use of the characteristics of the route according to a conventional search condition by weighting the movement cost of the road link overlapping with the past route. With the goal.

[0010]

In order to achieve the above object, the present invention has a first means for storing position detecting means for detecting a current position of a vehicle, road information / geographic information and route search data. And a destination is set from the road information / geographic information of the map data storage means and the map data storage means,
The input means for starting the route searching means and the departure point from the current position of the position detecting means are set, and the purpose is to operate the road information / geographical information and index information of the map data storing means by the input means. A point setting means for setting a place, a route search means having a route calculation means and a link cost updating means for calculating the shortest route at a minimum cost from a starting point to a destination set by the point setting means,
A route management unit for storing and managing the route result calculated by the route searching unit; and a display unit for displaying the road information / geographical information of the map data storage unit and the route result by the route managing unit. And

The second means further comprises dynamic traffic information receiving means for receiving dynamic traffic information in addition to the first means,
Traffic information response means for outputting the delay of travel time of each road obtained from the dynamic traffic information receiving means to update the link cost of the route searching means in order to use for changing the road link.

[0012]

According to the first and the second means of the present invention, in addition to the route calculation part for obtaining the shortest route connecting the starting point and the destination at the minimum cost in the conventional route searching device as the route searching means, A link for weighting and updating the cost of the link corresponding to the road link used in the existing route when the route search data is acquired from the map data storage unit by referring to the existing route result of the management unit By newly providing the cost update part, it is possible to calculate a result with less overlap with the existing route in the calculation of another route between the same starting point and destination.

By providing a road type code for each road link in the route search data of the map data storage means, the link cost update portion of the route search means selects the road type code and weights the costs. It is possible to calculate another route in which a link of a desired road type is treated with priority or non-priority.

The link cost updating portion of the route searching means includes node cost updating means for operating the cost of the node of the route searching data of the map data storing means, and the existing route management means has the same. A route that avoids a desired point on the route can be calculated.

Further, the link cost updating part of the route searching means refers to the distance traveled from the existing route of the route management means for the entire route and the arrival distance from the starting point for each road link in the route. Determine the distance from the origin and destination of the road link, and continue according to the reach distance for the road link near the departure side and according to the remaining distance to the destination for the road link near the destination side By changing the coefficient of cost change in a stepwise or stepwise manner, it is possible to suppress the difference from the existing route in the vicinity of the starting point and the destination and calculate another route in which the difference in the vicinity of the center of the route is emphasized.

[0016] Further, the route calculation part of the route search means individually proceeds with the route calculation from the departure side and the destination side, and when both route search ranges are joined, the entire route from the departure place to the destination is constructed. By using the two-way route search method, the link cost update part performs processing only in the route search specified by either the departure side or the destination side. Another route that emphasizes the difference on one side can be calculated.

Further, the route search data of the map data storage means is provided with hierarchical route search data which is a hierarchical road network selected according to stages such as road type, road width or maximum speed. The route calculation part of the means calculates the route using lower layered route search data in the vicinity of the starting point and the destination, and uses it according to the distance traveled from the starting point or destination or the amount of data required for the route calculation. A route search means for switching the route search data to an upper layer is provided, and a link cost updating part of the route search means sets a coefficient for changing the cost of a road link corresponding to an existing route individually for each layer. In this way, the degree of difference between different routes and existing routes is changed step by step at each stage of the hierarchy, and the difference according to the importance of the road is emphasized. The road can be calculated.

Further, according to the second means, the map data storage means includes a traffic information correspondence means for associating road information and traffic information, and the link cost updating part of the route search means manages the route. In addition to updating the cost of the road link corresponding to the existing route of the means, by operating the cost of the high-congestion road link or the regulated road link provided by the traffic information handling means, the current road conditions can be improved. It is possible to calculate a suitable dynamic alternative route.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing the configuration of a route search device in a first embodiment of the present invention. This example shows
The route management means 7 is added to the configuration of the conventional example shown in FIG. 16, and the route search means 5 is composed of a route calculation part 51 and a link cost update part 52. In addition, the same components as those in FIG. 16 are designated by the same reference numerals and the description thereof is omitted.

Here, the route management means 7 stores and manages the existing route search results. The route calculation part 51 of the route search means 5 is the same route calculation part as the route search means of FIG. Further, the link cost updating portion 52 refers to the result of the searched route of the same departure point / destination held by the route management means 7 when reading the route search data 22 of the map data storage means 2 to determine the existing route. This is a part for changing and updating the link cost of the corresponding road link.

Next, the operation of this embodiment having the above configuration will be described with reference to FIGS. First, when a destination is newly designated through the input means 3 and a route calculation is requested, the route calculation part 51 of the route search means 5 causes a new departure / destination by a signal from the point setting means 4 as in the conventional example. After calculating the first route result for the
At the same time, the route management means 7 saves the first route result.

Next, when another route at the set starting point and destination is requested through the input means 3, the link cost updating portion 52 of the route searching means 5 causes the route data to be searched from the map data storing means 2. A case where a corresponding road link is included by referring to past route results in the route management means 7 while reading 22 and determining whether or not a route link corresponding to an existing route is included in the route search data 22. Is rewritten by multiplying the moving cost of the road link by a predetermined coefficient and weighting it.

The route calculation part 51 of the route search means 5 calculates a route different from the past route by performing a route search based on the route search data in which the cost of the road link is updated by the above method. You can The alternative route thus obtained is added to the storage content of the route management means 7 in preparation for the selection of a new alternative route. The route managing means 7 erases the stored past record when a new departure place / destination or a search condition is set and the reference of the existing route result becomes unnecessary.

FIG. 2 shows the relationship of the route search data 22 in the map data storage means 2, and FIG. 3 shows its geometrical network structure. In FIG. 3, the nodes correspond to the positional relationships such as intersections in the road network on the map, boundary points of routes, start points and end points of toll roads, etc.
The links (indicated by black circles) indicate the connection relationship when moving from one node to another node, and correspond to the part of the road cut off at the point corresponding to the node such as an intersection in the actual road network. To do.

A link for entering from an adjacent node and a link for leaving to an adjacent node are connected to one node. In the node table 22a of the route search data 22 of FIG. 2, each node is connected. record
For (1), (2) ..., the number of links 22a-1 to be connected and each road link number 22a-2 are recorded. In the road link table 22b, each road link record (1),
(2) ... Node number 2 in the destination direction, which is the connection relationship
2b-1, a road type code 22b-2 as an attribute, a link total length 22b-3, and a travel cost 22b-4 for each search condition are recorded.

Next, the procedure of the route search process using the route search data 22 shown in the format of FIG. 2 will be described as a method called Dijkstra method. The route calculation part 51 of the route search means 5 of FIG. 1 uses the departure point node set for the route search data 22 as a reference node, and connects from there by the node table 22a of the route search data 22 shown in FIG. The road link number 22a-2 and the movement cost 22b-4 are acquired in order, and the node that can be reached at the lowest cost is found among them.

The node which gives the minimum arrival cost is set as the next reference node, and at the same time, the arrival cost from the starting point to the reference node and the immediately preceding link number or the immediately preceding node number are recorded in the search result recording area. The node table is searched again from the new reference node to find an unsearched node having the minimum arrival cost from the adjacent departure place. By repeating the above operation, the reference node moves from the place of departure in the ascending order of arrival cost, and the searched area is expanded on the network. In this way, when the reference node reaches the destination node, the route that gives the minimum cost between the starting point and the destination is constructed by tracing the immediately preceding link from the destination to the starting point.

FIG. 4 shows a flow of another route search processing. This is the route search apparatus according to the first embodiment of the present invention. It shows that another route that has a difference from the shortest route is calculated with a certain cost.

First, the route search means 5 reads the route search data 22 from the map data storage means 2 (step S1, the same applies hereinafter), and then the link cost update part 52 causes the route management means 7 to have the same departure point. While referring to the past route results (existing route link numbers) of the destination and the same search condition, all the road links included therein are performed (S2). That is, in S2, the loop processing is performed for each of the link numbers of the existing route from the beginning to the end. In this way, it is found from the road link table 22b of the route search data 22 of the road link record of the corresponding number, and the moving cost 22b-4 is multiplied by a constant number and updated (S3). That is, in S3, the cost of the road link record corresponding to the link number of the existing route is changed.

In the road network for which the link cost updating process has been performed in this way, the previous shortest route no longer gives the minimum cost, and another route is calculated by performing a new route calculation process (S4). The result of the alternative route thus obtained is stored in the route management means 7 for use in a new alternative route search, and then displayed on the display means 6.
(S5).

At the time of the alternative route search processing, in S3 of FIG. 4, the road type code 22 of the road link record shown in FIG.
Referring to b-2, the weighting coefficient to be applied to the cost is switched according to the road type, or the cost is changed only for a specific road type to give a priority order according to the road type or on the original route. Another route that avoids the desired road type can be obtained.

Further, by providing a passage prohibition flag in the node record of the route search data 22 shown in FIG. 2 and designating passage prohibition of a specific node on the existing route, a desired existing point on the route can be avoided. Another route is required. In step S3 of FIG. 4, a node record corresponding to the designated passage prohibition node on the existing route is found from the route search data, and a passage prohibition flag is set. In the route search process,
By treating the arrival cost to the node with the passage prohibition flag as infinity, the designated node is excluded from the reference node and excluded from the route.

Further, in the above method, the cost of the road link record corresponding to the existing route in the route search data may be updated irrespective of the position in the route, and in some cases, the existing route may be updated. On the other hand, the difference in route may appear only near the starting point and the destination. In order to prevent this, when referring to an existing route, considering the positional relationship of the entire route, the cost is hardly changed near the departure point and the destination, and the cost is updated in the middle part of the route. A method of increasing the coefficient multiplication is used so that it does not affect the route of the part connecting to the starting point and the destination.

FIG. 5 is a diagram for explaining the switching of the link cost update rate according to the arrival distance from the departure point / destination,
The horizontal axis shows the ratio between the starting point and the destination at the position occupied by the link from the starting point a to the destination b, and the vertical axis shows the multiple of the cost coefficient.

As shown in FIG. 5, in the link cost updating process of the route search data 22 of FIG. 2, the cost weighting at the center of the route is re-increased by dividing the existing route into 5 equal parts. The cost change rate is set at three levels so that

In FIG. 6, in the route calculation portion 51 of the route searching means 5 of FIG. 1, the search ranges are expanded simultaneously or alternately from both the departure side and the destination side, and the two search ranges are combined. The conceptual diagram of the bidirectional route search process in which the minimum cost route between the departure place and the destination is obtained at the time point is shown. 6 (a) and 6 (b) show the expansion of the search range in the route search from the departure side and the destination side, respectively, and (c) is the search range of (a) and (b). Shows how the routes between the starting point and the destination are combined. 51 in FIG.
a is the range of route search data, 51b is the departure node, 51c
Represents a search range from the starting point, 51d represents a destination node, 51e represents a search range from the destination, and 51f represents a minimum cost route between the starting point and the destination.

FIG. 7 shows a processing procedure flow for emphasizing only the difference on the departure place side in selecting another route by the bidirectional route search shown in FIG.

First, the start processing of the route search by departure side (S
As 6), after setting the departure node and the destination node, the route search work areas on the departure side and the destination side are respectively initialized (S7, S8). Next, the search area on the departure side and the search area on the destination side are compared to determine whether or not a common road link or node is included in both search areas (S9). If there is no common link or node, the search ranges on the departure side and the destination side are expanded until a certain searched node is added (S10,
Return to the determination of S11) and S9. By ending the expansion of the search range at the time when a common road link or node is found in both searched results in S9 and tracing the link or node immediately before the common link to the departure side and the destination side. Configure the route.

Here, in the case of emphasizing the difference of another route on the side of the departure place, in the search range expansion processing S10 on the side of the departure place,
Immediately after the route search data is read (S12), the link number of the existing route is referred to (S13) and the cost of the corresponding road link record is updated (S14) to perform the route calculation process (S15). Further, in the search range expansion processing (S11) on the destination side, the route map data is read (S16) and the route calculation processing is executed as it is (S17). Another route is selected by changing the search result on the departure side by the above method.

FIG. 8 shows a hierarchized route search process using route search data classified according to the level of road, width of road, speed limit or average passing speed of each road, and data amount. The conceptual diagram demonstrated is shown. FIG.
In the hierarchized route search process, the route search is divided into three stages from hierarchy 1 to hierarchy 3, and the process proceeds independently on the departure side and the destination side until the search areas are combined.

In FIG. 8, reference numerals 801, 802, and 803 are route search data in Layer 1, Layer 2, and Layer 3, respectively. 804 and 805 are the starting point and the destination, respectively, and 806 and 8
07 is the search range in Level 1 on the departure side and the destination side, 80
Reference numerals 8 and 809 denote search ranges in the hierarchy 2 on the departure side and the destination side, and reference numerals 810 and 811 denote search ranges in the hierarchy 2 on the departure side and the destination side. Reference numeral 812 indicates a route result obtained by combining search ranges in the highest search hierarchy, and reference numeral 813 indicates a connection relationship of the route results between the hierarchies.

Next, the operation of the hierarchized route search processing will be described with reference to FIG. First, the search for the departure point 804 and the destination 805 is expanded as a normal search at the lowest level, level 1. When the lowest search ranges 806 and 807 have expanded to some extent, it is confirmed whether the links connecting to the nodes on the outer periphery of the respective search ranges have a correspondence relationship with the upper hierarchy, and those with correspondence have a higher relationship. The search state is moved to the hierarchy, and when the search data is sufficiently transferred to the upper hierarchy, the search for the lower hierarchy is stopped and the search for the upper hierarchy is started at the same time. As a result, on the network of the route search data of the hierarchy 2 and above, the search is started by taking over the final search result of the lower hierarchy, so that the search ranges 808 and 809 on the hollow disk of FIG. 8 are formed. In the route search process in the highest layer, the bidirectional route search process shown in FIG. 6 is excluded except that the search is started by inheriting the search result from the lower layer instead of the origin / destination. Is the same as.

In the hierarchical route search, according to the distance between the starting point and the destination and the number of nodes and links included in the search range,
The layer to which the process is advanced is switched step by step, and the finally obtained route result is also composed of the link number / node number corresponding to the layer to which the search is advanced.

FIG. 9 shows the format of the hierarchical route search data, which is different from the format of the route search data 22 shown in FIG.
A parent link correspondence table 22c, which records the correspondence between the road links in the current hierarchy and the links (parent links) in the upper hierarchy, is newly added.

That is, the parent link corresponding record has a road hierarchy level 22c-1, a parent link number 22c-2, and a parent link start position 22.
c-3 and parent link end position 22c-4 etc. are recorded.

FIG. 10 is an explanatory diagram of the correspondence relationship of road links between layers, (a) shows the correspondence relationship between the upper and lower hierarchy networks, and (b) shows the correspondence relationship between the upper and lower hierarchy links. . In FIG. 10 (a), the upper hierarchical network 1002 extracts the road types with a particularly high degree of importance and a wide road width from among the road links in the lower hierarchical network 1001 and the network is configured. It represents. FIG.
In (b), the road link number of the current layer and the corresponding parent link number and the start position 1005 and the end position 1006 of the current link with respect to the parent link are recorded for the road common to the road links 1004 and 1003 between the upper and lower layers. ing.

Next, FIG. 11 is a diagram showing a flow of link cost update processing and selection of another path in the hierarchical path search processing. The result of the existing route recorded in the route management means 7 shown in FIG. 1 includes the link number and the node number classified by hierarchy as shown in S18 of FIG. The link cost updating unit 52 of the route search means 5 of FIG. 1 first checks whether or not there is a road link in the route search data in the currently searched layer that matches the same layer link of the existing route (S28). , S29), if the matching link is found, the movement cost of the road link number record in the route search data 22 is updated at a scaling factor according to the hierarchy (S30).

Next, it is checked by the parent link correspondence table on the existing route side whether the link of the lower hierarchy corresponding to the road link in the route search data 22 exists in the existing route (S31), and they match. If a link is found, the movement cost of the road link number record in the route search data 22 is updated at a rate according to the currently searched layer (S32).

Similarly, the parent link correspondence table 22c is used to check whether or not there is an upper hierarchical link corresponding to the road link in the route search data 22 in the existing route.
(S33 to S35) If the matching link is found, the movement cost of the road link number record in the route search data 22 is updated at a scaling factor according to the currently searched layer (S36, S37).

As described above, every time the search hierarchy shifts and the new route search data 22 is read by the route search means, the route management means 7 takes a corresponding link in the existing route and links it. By performing the route calculation after updating the cost, not only can another route having a certain difference be obtained even in the hierarchical route search, but also by the hierarchical route selection process of the hierarchical route search of FIG. It is possible to obtain a rational alternative route that emphasizes the difference at the center of the route by using the link cost updating coefficient according to the search hierarchy as shown in the link cost coefficient of. In FIG. 12, the horizontal axis indicates the parts 1201, 1202, 1203 belonging to the respective floors 1, 2, 3 from the starting point a to the destination b, and the vertical axis indicates the search layers of the respective floors 1, 2, 3. The corresponding link cost factors are shown.

FIG. 13 is a block diagram showing the configuration of the route search device in the second embodiment of the present invention. In this embodiment,
Two means 8 and 9 are newly added to the route search device of the first embodiment of FIG. 8 is a dynamic traffic information receiving means for receiving traffic congestion information / regulation information for each road link provided from the social infrastructure, and 9 is traffic congestion information / regulation information etc. acquired by the dynamic traffic information receiving means 8. Is a traffic information correspondence means for associating the traffic information of the above with the route search data 22.

The traffic information acquired by the dynamic traffic information receiving means 8 is stored in the format shown in FIG.
The regulation information 1402 is arranged in the numerical order of the road links (traffic information links 1403) established by the social infrastructure.

Here, the route search data 22 has a format as shown in FIG. 15 and a traffic information correspondence table 22d is newly added to the format of FIG. 2 to provide information provided by the traffic information link. Can be made to correspond to the link number of the road link table. In the traffic information handling means 9,
Using the traffic information correspondence table 22d of the route search data 22, the traffic information provided in the format of FIG. 14 is used as the route search data.
Convert to a format compatible with 22 road link records. Further, the link cost update part 52 of the route search means 5 refers to the traffic information converted in the order of the road link records, and updates the cost of the route search data. As a procedure for selecting another route corresponding to the dynamic traffic information, in contrast to the procedure shown in FIG. 4, immediately after updating the link cost corresponding to the existing route in S2 and S3, the traffic congestion information / regulation information is added. The corresponding cost update is processed by the same method, and then the route calculation of S4 is performed.

[0054]

As described above, according to the first means of the present invention, the route calculation means is used as the route search means in the route calculation part for obtaining the shortest route connecting the starting value and the destination at the minimum cost in the conventional route search device. In addition, the cost of the link corresponding to the road link used in the existing route is weighted when the route search data is acquired from the map data storage unit by referring to the existing route result of the route management unit. By providing a new link cost update part to be updated, it will be difficult to select road links included in the existing route in new calculation of another route between the same starting value and destination, and it is clear that the existing route is This has the effect of being able to reliably calculate another route having different differences.

Further, the road type code for each road link is provided in the route search data of the map data storage means, and the link cost updating portion of the route search means selects the road type code to weight the costs. Allows preferential or non-priority treatment of links of desired road types without being restricted by the number of cost types pre-recorded in the route search data, and features such as priority or non-priority for each road type This has the effect that another route can be calculated.

Further, the link cost updating portion of the route searching means is provided with the node cost updating means for operating the cost of the node of the route searching data of the map data storing means, whereby the route managing means is provided. This has the effect of being able to calculate another route that avoids a desired point on the existing route of the.

Further, the link cost updating portion of the route searching means refers to the distance traveled from the existing route of the route management means for the entire route and the distance reached from the starting point for each road link in the route. Judge the distance from the origin and destination of the road link, according to the reach distance for the road link near the departure side, according to the remaining distance to the destination for the road link near the destination side By changing the coefficient of cost change continuously or stepwise, it has the effect that the difference from the existing route can be suppressed near the starting point and the destination and another route can be calculated by emphasizing the difference near the center of the route. .

Further, the route calculation part of the route searching means individually calculates the route from the departure side and the destination side, and when the route search ranges of both sides are joined, the entire route from the departure place to the destination is constructed. By using the two-way route search method, the link cost update part performs processing only in the route search specified by either the departure side or the destination side. This has the effect of being able to calculate another route that emphasizes only the difference on one side on the ground side.

Further, the route search data of the map data storage means is provided with hierarchical route search data which is a hierarchical road network selected according to a stage such as road type, road width or maximum speed. The route calculation part of the means calculates the route using lower layered route search data in the vicinity of the starting point and the destination, and uses it according to the distance traveled from the starting point or destination or the amount of data required for the route calculation. It is a hierarchy-based route search means for switching the route search data to an upper hierarchy, and the link cost update part of the route search means sets a coefficient for changing the cost of a road link corresponding to an existing route for each hierarchy. , The difference between the existing route and another route according to the hierarchical level of the existing route in the hierarchical network configured by road type and importance To control, certain of the road network and the departure point -
This has the effect of being able to calculate another route in which the difference is emphasized or suppressed by limiting the vicinity of the destination.

According to the second means, the map data storage means further comprises dynamic traffic information receiving means, and the map data storage means is traffic information correspondence means for associating road information with traffic information. The link cost updating part manipulates the cost of the road link having a high degree of traffic congestion or the regulated road link provided by the traffic information handling means in addition to the cost update of the road link corresponding to the existing route of the route management means. This not only emphasizes the difference from the existing route, but also has the effect of calculating a more practical alternative route that matches the current road conditions.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a route search device in a first exemplary embodiment of the present invention.

FIG. 2 is an example diagram showing a relationship between route search data in the map data storage means of FIG.

FIG. 3 is a diagram showing a network structure of the route search data of FIG.

FIG. 4 is a flowchart of another route search processing according to the first embodiment of this invention.

FIG. 5 is a diagram for explaining switching of link cost update rates depending on the reach distance from a departure place / destination in step S3 of FIG. 4;

FIG. 6 is a conceptual diagram illustrating a bidirectional route search process from a departure point / destination of a route calculation part in the route search means of FIG.

FIG. 7 is a flow chart for selecting a route by departure side in the bidirectional route search of FIG.

FIG. 8 is a conceptual diagram illustrating a hierarchical route search process according to the first embodiment of this invention.

9 is a diagram showing the format of the hierarchized route search data of FIG.

FIG. 10 is a diagram illustrating a correspondence relationship of road links between layers.

FIG. 11 is a flowchart of link cost update processing and alternative route selection in the hierarchical route search means.

FIG. 12 is a diagram showing link cost coefficients for each layer in another route selection process of hierarchical route search.

FIG. 13 is a block diagram showing a configuration of a route search device in a second exemplary embodiment of the present invention.

14 is a diagram showing a format of traffic information acquired by the dynamic traffic information receiving means of FIG.

FIG. 15 is an example diagram showing a relationship between traffic information-corresponding route search data recorded in the route search data of FIG. 13;

FIG. 16 is a block diagram showing a configuration example of a route search device in a conventional navigation device.

[Explanation of symbols]

1 ... Position detecting means, 2 ... Map data storing means, 3 ...
Input means, 4 ... Point setting means, 5 ... Route searching means,
6 ... Display means, 7 ... Route management means, 8 ... Dynamic traffic information receiving means, 9 ... Traffic information responding means, 21 ... Road information / geographic information, 22 ... Route search data, 51 ... Route calculation part, 52 ... Link cost update part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoichiro Suga, Yoichiro Suga, 3-1, Tsunashima-higashi, 4-chome, Kohoku-ku, Yokohama-shi, Kanagawa Matsushita Communication Industrial Co., Ltd. 3-3-1 Matsushita Communication Industrial Co., Ltd. (72) Inventor Kenji Tamura 4-3-1 Tsunashima East, Kohoku Ward, Yokohama City, Kanagawa Matsushita Communication Industrial Co., Ltd.

Claims (11)

[Claims] 1. A position detection means for detecting the current position of a vehicle, a map data storage means for storing road information / geographic information and route search data, and a destination based on the road information / geographic information of the map data storage means. And input means for activating the route search means described later, and the departure point is set from the current position of the position detection means, and the road information / geographical information and index information of the map data storage means by the input means are set. Point setting means for setting a destination by operation, and route searching means having means for calculating a shortest route from the starting point set by the point setting means to the destination at the minimum cost and link cost updating A route management unit for storing and managing the route result calculated by the route searching unit, road information / geographical information in the map data storage unit, and the route management Display means for displaying the route result by the means. 2. A position detecting means for detecting the current position of the vehicle, a map data storing means for storing road information / geographic information and route search data, and a destination from the road information / geographic information of the map data storing means. And input means for activating the route search means described later, and the departure point is set from the current position of the position detection means, and the road information / geographical information and index information of the map data storage means by the input means are set. Point setting means for setting a destination by operation, and route searching means having means for calculating a shortest route from the starting point set by the point setting means to the destination at the minimum cost and link cost updating A route management unit for storing and managing the route result calculated by the route searching unit, road information / geographical information in the map data storage unit, and the route management Display means for displaying route results by means, dynamic traffic information receiving means for receiving dynamic traffic information, and delay of travel time of each road obtained from the dynamic traffic information receiving means for changing road links And a traffic information handling means for outputting to the link cost updating means of the route searching means. 3. The route searching means, a link cost updating means for changing a movement cost of a link belonging to an existing route held by the route managing means, and a route calculating means for calculating a route connecting two nodes at a minimum cost. The route search device according to claim 1 or 2, further comprising: 4. The route searching means associates a node with a point and an intersection of a road network on a map in a road network, and associates a link with a connection relation, a distance, and a travel time on a road connecting the intersections on the map. The route search device according to claim 1 or 2, wherein a new route having a difference with respect to the existing route is obtained. 5. The route searching means obtains a plurality of routes in ascending order of distance or travel time from the current location to the destination by associating two points with the current location and the destination. 1. The route search device according to 1 or 2. 6. The route search means, in the road network, each link has a road type code corresponding to a road link in the map data, and the road type is limited to move costs such as link distance or travel time. The route search device according to claim 1 or 2, wherein a plurality of routes in which differences between road links belonging to a desired road type are emphasized are obtained by changing. 7. The route searching means designates a node corresponding to an arbitrary point on an existing route in a road network, sets a passage prohibition flag on the node, or sets a movement cost of a link connected to the node. The route search device according to claim 1 or 2, wherein a route that bypasses the designated point is obtained by increasing the number. 8. The route searching means refers to the overall distance of the existing route and the reaching distance from the starting point for each individual road link in the existing route, and the closer one of the starting point and the destination is determined. By finding a different route that emphasizes or suppresses the difference near the starting point or destination by changing the magnification of the coefficient that changes the moving cost of the target link according to the reach distance / arrival cost from or the number of road links The route search device according to claim 1 or 2. 9. The bidirectional route search means individually advances the route calculation from the departure side and the destination side, and forms an entire route from the departure place to the destination when the route search ranges of both sides are joined. By using the route search method and changing the movement cost of the road link only by calculating the route on one side of the starting point or destination, the difference of the route belonging to one side of the starting point or the destination side with respect to the existing route The route search device according to claim 1 or 2, wherein another route emphasized is obtained. 10. The route searching means uses a hierarchical road network selected according to a stage such as a road type, a road width, a maximum speed, etc., and a lower layer for route calculation in a peripheral area of a starting point and a destination. Using existing data for each layer, the existing route is supported for each layer by using the hierarchy-based route search method that switches the road network used to a higher layer according to the amount of data required to calculate the distance traveled from the origin or destination By changing the coefficient for changing the traveling cost of the road to be used, another route is obtained by adjusting the difference according to the degree of importance of the road, which is the degree of difference between the existing routes. Item 1. The route search device according to item 1 or 2. 11. The traffic information handling means uses the delay in travel time of each road obtained from the dynamic traffic information receiving means to change the cost of a road link, thereby making them different from each other according to the current road conditions. The route search device according to claim 2, wherein a plurality of routes are obtained.