JP5363853B2 - Guide route creation device, guide route creation method, and computer program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently prepare a guiding route which passes through all the passing object roads. <P>SOLUTION: This device for preparing the guiding route includes a network storage part which stores road network data containing a plurality of nodes and links; a passing object link recognizing part which recognizes the links corresponding to the roads to be passed through, as passing object links; a processing object node recognizing part which recognizes all of the nodes connected to the passing object links, as processing object nodes; an entry-escape determining part which executes processing for determining, regarding a noticed node being one of the processing object nodes, one-to-one combination of an entry link for entering the noticed node with an escape link for escaping from the noticed node, while regarding all of the processing object nodes as the noticed nodes; and a guidance route preparing part which prepares the guidance route passing through all of the passing object links, on the basis of the determined combination of the entry link and the escape link. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a guide route creation device, a guide route creation method, and a computer program.

  For example, a technique for providing route guidance to a car or a pedestrian using map data digitized so as to be usable by a computer, including a car navigation apparatus, has been widely put into practical use. At this time, the technology of how to efficiently create a guide route that passes through the road to be passed, such as route guidance for sales visit route and route guidance for road survey, etc. Development is underway. (For example, patent document 1).

Japanese Patent Laid-Open No. 7-244689 JP-A-7-249025 JP-A-8-329041 Japanese Patent Laid-Open No. 9-160981

  An object of this invention is to provide the technique which produces efficiently the guide route which passes all the roads to pass.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1] A guide route creation device,
A network storage unit for storing road network data including a plurality of nodes and links connecting the nodes;
Among the links included in the road network, a passage target link recognition unit that recognizes a link corresponding to a road to be passed as a passage target link;
A processing target node recognition unit that recognizes all nodes connected to the plurality of passing target links as processing target nodes among the nodes included in the road network;
For the node of interest that is one of the nodes to be processed, the entry / exit determination process for determining a one-to-one combination of an entry link entering the node of interest and an exit link exiting from the node of interest An entry / exit determination unit that executes a processing target node as the target node;
Based on the determined combination of the entry link and the exit link, a guidance route creation unit that creates a guidance route that passes through all the passage target links;
A guide route creation device comprising:
In this way, for all the processing target nodes, after determining the one-to-one combination of the entry link and the exit link, a guide route that passes through all the target links is created, so the creation speed of creating the guide route is improved. can do.

[Application Example 2] The guidance route creation device according to Application Example 1,
When the number of the plurality of passage target links connected to the node of interest is an odd number, the entry / exit determination unit replicates one of the plurality of passage target links and virtually A pair of the entry link and the exit link for the node of interest by adding as a passage target link by adding as a passage target link, or by adding a passable link among the links that are not the passage target. A guide route creation device that determines one combination.
In this way, by determining the one-to-one combination by making the number of incoming links and outgoing links equal, it is possible to create a guide route that passes through all the passage target links.

[Application Example 3] The guide route creation device according to Application Example 1 or Application Example 2 further includes:
For all of the links to be passed, a directed processing unit that determines a passing direction according to a predetermined condition,
The entry / exit determination unit is a guide route generation device that determines a one-to-one combination of the entry link and the exit link according to a determined passing direction of the passage target link.
Since the one-to-one combination of the entrance link and the exit link is determined after all of the passing target links are directed, the creation speed of creating the guide route is improved from the state including the links that are not directed. Can do.

[Application Example 4] The guidance route creation device according to Application Example 3,
The predetermined route includes a guide route generation device including observing traffic regulations.
In this way, a guidance route that complies with traffic regulations can be created.

[Application Example 5] The guide route creation device according to Application Example 3 or Application Example 4,
The predetermined condition in the directed processing unit includes a guide route generation device including reducing a difference between the number of the incoming links and the number of the outgoing links of the node of interest.
In this way, a one-to-one combination of the entrance link and the exit link can be determined efficiently later.

[Application Example 6] The guidance route creation device according to any one of Application Example 3 to Application Example 5,
The predetermined condition includes a guide route generation device including reducing a passing cost when passing through the node of interest.
In this way, it is possible to create a guide route that can efficiently pass the road corresponding to the passage target link.

[Application Example 7] The guidance route creation device according to any one of Application Example 1 to Application Example 6,
The entry / exit determination unit is a guide route generation device that determines a one-to-one combination of the entry link and the exit link so as to reduce a passing cost when passing through the node of interest.
In this way, it is possible to create a guide route that can efficiently pass the road corresponding to the passage target link.

[Application Example 8] The guidance route creation device according to any one of Application Examples 1 to 7,
The entry / exit decision unit
Among the nodes to be processed, an exit shortage node having a number of exit links that is less than the number of the incoming links is set as a departure node, and among the nodes to be processed, the number of entrance links is less than the number of the exit links. Search for additional routes with the missing node as the destination node,
By adding a link corresponding to the additional route to the passage target link, the number of the incoming links and the number of the outgoing links are made equal for each processing target node,
A guide route creation device that determines a one-to-one combination of the entry link and the exit link.
In this way, since the number of entry links and the number of exit links are equalized, a one-to-one combination of entry links and exit links is determined. Therefore, a one-to-one combination of entry links and exit links is definitely determined. To create a guide route.

[Application Example 9] The guidance route creation device according to any one of Application Example 1 to Application Example 8,
The guide route creation unit creates a single stroke route according to a combination of the entry link and the exit link,
When a plurality of one-stroke paths are created, the combination pattern of the entry link and the exit link is changed for the processing target node in which a plurality of combinations of the entry link and the exit link are allowed. Thus, a guide route creating apparatus that connects a plurality of one-stroke paths and finally creates the guide route consisting of one one-stroke path.
In this way, one final guide route can be created efficiently.

[Application Example 10] The guidance route creation device according to Application Example 9,
The entry / exit determination unit changes the combination pattern of the entry link and the exit link to a pattern having the lowest passage cost when three or more combinations of the entry link and the exit link are allowed. Guide route creation device.
In this way, it is possible to create a guide route that can efficiently pass the road corresponding to the passage target link.

  The present invention can be realized in various forms, such as a guide route creation method, a computer program for causing a computer to create a guide route, and a recording medium on which the computer program is recorded. can do.

It is explanatory drawing which shows schematic structure of the guidance route creation apparatus as an Example. It is a figure explaining the contents of map data D11. It is the figure which represented an example of the road of the area used as the object of preparation of a guidance route with the network of a node and a link. It is a flowchart which shows the process step of the guidance route creation process in an Example. It is a 1st figure explaining the directing of the passage object link LKS. It is a 2nd figure explaining the directing of the passage object link LKS. It is a 3rd figure explaining the direction of the passage object link LKS. It is a 4th figure explaining directionality of the passage object link LKS. It is a 1st figure explaining the calculation in the case of determining the one-to-one combination of an exit link and an approach link about an undirected link. It is a 2nd figure explaining the calculation in the case of determining the one-to-one combination of an exit link and an approach link about an undirected link. It is a figure explaining the calculation in the case of determining the one-to-one combination of an escape link and an approach link in a present Example. It is a 1st figure explaining determination of the one-to-one combination of an approach link and an exit link. It is a 2nd figure explaining determination of the one-to-one combination of an approach link and an exit link. It is a 1st figure explaining the process which adds a passage coping link. It is a 2nd figure explaining the process which adds a passage coping link. It is a figure explaining determination of a one-stroke path. It is a figure explaining the change of the combination of an approach link and an escape link. It is a flowchart which shows the process step of the guidance route creation process in a 1st modification.

  Hereinafter, embodiments of the present invention will be described based on examples with reference to the drawings.

A. Example:
・ Configuration of guide route creation device:
FIG. 1 is an explanatory diagram illustrating a schematic configuration of a guide route creation device as an embodiment. The guide route creation apparatus 200 is a known computer such as a large computer or a personal computer. The guide route creation device 200 includes an input / output unit 202 that is an interface with a CPU 201, an internal storage device 203 such as a RAM and a ROM, an external storage device 204 such as a hard disk, and an external device (for example, a keyboard and a mouse). I have.

  The external storage device 204 stores map data D11. FIG. 2 is a diagram for explaining the contents of the map data D11. The map data D11 includes an image database CD1, a route database CD2, and an attribute database CD3. FIG. 2 conceptually shows the contents of the image database CD1, the route database CD2, and the attribute database CD3.

  In the image database CD1, data representing a map image (map image data) is stored in a vector data format. The map image data may be stored in a raster data format such as a bitmap format or a JPEG data format instead of the vector data format. The map image data includes data representing the shape of topography, buildings, roads, and the like.

  The route database CD2 stores route data related to a traffic route existing in an area corresponding to the map image represented by the map image data. The route data is data representing a network indicating the arrangement of traffic routes on the ground surface. The network data includes node data representing element points ND (referred to as nodes) in the traffic route and link data representing line segments LK (referred to as links) connecting the nodes. The node ND represents, for example, an intersection, a branch point, an end point, a start point, a boarding / exiting position such as a station, and the like. The link LK represents a traffic route such as a roadway, a track, and a pedestrian road.

  The attribute database CD3 stores attribute data. The attribute data is information associated with the node ND or the link LK and indicating the attribute. The attribute data includes various data related to the node ND and the link LK. For example, the attribute data associated with the link LK includes the name of the link LK (for example, the name of the road), the type of the link LK (for example, a highway), and the restriction information of the link LK (for example, one-way traffic). ), Other information (for example, if it is an expressway, it may include a section fee). The attribute data associated with the node ND is associated with the name of the intersection corresponding to the node ND, the restriction information of the intersection corresponding to the node ND (for example, left turn is possible, right turn is not allowed, straight travel is allowed, etc., as viewed from a certain direction), Image data representing an image related to the node ND (for example, a schematic diagram showing a branching state of the node ND (for example, an intersection or a station) or an image showing a guide board) may be included. One or more attribute data may be associated with one node ND or link LK. Further, the attribute database CD3 does not have to be a single database. For example, attribute data related to an expressway, attribute data related to a property such as a store or a station, and attribute data related to regulation information may be separate databases.

  A path creation program is stored in the internal storage device 203, and the functions of the functional blocks illustrated in the internal storage device 203 in FIG. 2 are realized by the CPU 201 executing the program. The realized functional blocks include a passage target link recognition unit M11, a processing target node recognition unit M12, a link directing processing unit M13, an approach / exit determination unit M14, and a route guidance creation unit M15.

  The passage target link recognition unit M11 receives, for example, an operator input via the input / output unit 202, and passes through the guide route to be created from the links LK included in the route database CD2 of the map data D11. The link (passage target link) LKS corresponding to the road to be recognized is recognized. The processing target node recognition unit M12 selects all nodes (processing target nodes) NDS connected to both ends of the plurality of recognized passing target links LKS from the nodes ND included in the route database CD2 of the map data D11. recognize. The link directing processing unit M13 determines the passage direction for all the passage target links LKS according to a predetermined condition described later. For each of the processing target nodes NDS, the entry / exit determination unit M14 includes a link (entry link) that enters the processing target node NDS and a link that exits from the processing target node NDS for the link LK connected to the processing target node. A one-to-one combination is determined. Here, the combination of the entry link and the exit link is determined at least for the passage target link LKS connected to the processing target node NDS. The route guidance creation unit M15 creates a guidance route that passes through all the passage target links LKS based on the combination of the entry link and the exit link.

  FIG. 3 is a diagram illustrating an example of a road in a region for which a guide route is to be created, using a network of nodes and links. In FIG. 3, black circles and double circles represent nodes ND, and thin lines and thick lines represent links LK. Of the links LK, what is represented by an arrow is associated with a link LK corresponding to a one-way road in the direction of the arrow, that is, attribute information representing one-way in the direction of the arrow as attribute information. Represents the link LK being made. Of the links LK, those represented by simple straight lines that are not arrows represent links LK corresponding to roads that can pass in both directions. Of the links LK, the links indicated by bold lines represent the passage target links LKS. Among the nodes ND, double circles represent the processing target node NDS. Hereinafter, a guidance route creation process for creating a guidance route that passes through all the passage target links LKS specified as shown in FIG. 3 will be described.

Operation of the guide route creation device 200:
FIG. 4 is a flowchart illustrating the processing steps of the guidance route creation process in the embodiment. The guide route creation process is a process executed by the CPU 201. When the guide route creation process is started, the CPU 201 directs all the passage target links LKS. Directing is to define the passage direction of the passage target link LKS.

  5 to 8 are diagrams for explaining the directing of the passage target link LKS. 5 to 8, a white circle represents a node ND, and an alphabet for identifying the node is added to the white circle. In the following, the node ND may be described by using alphabets attached in white circles. For example, a node ND with “A” in a white circle is described as node A. 5 to 8, all the lines connecting the nodes represent links. 5 to 8, a link indicated by a dashed-dotted thick line represents an undirected passing target link LKS, and a link indicated by a dashed-dotted thick-line arrow is already in the direction of the arrow. It represents the link LKS to be passed. A link represented by a thin line represents a link that is not a passage target link LKS. Moreover, the thin broken arrow and x mark displayed in the vicinity of a node represent traffic restrictions at the node. For example, the node A shown in FIG. 5A is prohibited from turning right when entering from the node D side and prohibited from turning left when entering from the node B side. In FIGS. 5 to 8, in the right side of the white thick arrow, the link represented by the solid thick arrow is the passage target link LKS directed in the white thick arrow step. Represent.

  In the directing, it is one condition to comply with traffic regulations, and the CPU 201 directs the passing target link LKS corresponding to the one-way road in the direction in which it can pass. For example, as shown in FIG. 5 (a), when passage in the direction from node A to node C is restricted due to traffic restrictions, the passage target link LKS connecting between node A and node C is , Directed in the direction from node C to node A. Further, as shown in FIG. 5 (b), when there is a passing target link LKS directed in the direction of entering from the node B to the node A, traffic regulation occurs when the passing target link LKS is passed. Therefore, the passage target link LKS connecting the node A and the node C is directed in the direction from the node A to the node C.

  The passing target link LKS that has already been directed to the passing target link LKS and is connected to the two-way road is directed to travel along the road. For example, in the example shown in FIG. 6A, since the passing target link LKS connecting the node A and the node D is already directed in the direction from the node A to the node D, the node B and the node The link to be passed LKS connecting with A is directed in the direction from the node B to the node A. In addition, if a link that is not a passage target link LKS is included, a node that is four-difference connected is also connected to the already-directed passage target link LKS by a two-way connection if only the passage target link LKS is viewed. The passage target link LKS is also directed so as to travel along the road. For example, in the example shown in FIG. 6B, since the passing target link LKS that connects between the node B and the node A is already directed in the direction from the node B to the node A, the node A and the node A The link to be passed LKS connecting with C is directed in the direction from node A to node C.

  Also, the number of outgoing links that are directed in the direction of exiting from a certain processing target node (target node) to another processing target node, and the direction of entering from the other processing target node to the target node. The passing target link LKS is directed so that the difference in the number from the incoming link that is a directed link approaches zero. For example, in the example shown in FIG. 7A, since two exit links from the target node A are already determined, the other two passage target links LKS that are not directed are connected to the target node A. Directed to be an ingress link. Further, in the example shown in FIG. 7B, since two ingress links to the target node A have already been determined, the passing target link LKS between the target node A and the node C that is not directed is Directed to be an escape link from the node of interest A.

  In addition, when there is a passing target link LKS connected to the node of interest that has already been directed, other passing so that the directed passing target link LKS can pass the node of interest at as low a cost as possible. The target link LKS is directed. The passage cost represents the length of time required for passage. The longer the time required for passage, the higher the passage cost. The shorter the passage time, the lower the passage cost. For example, compared to a right turn or a left turn, going straight costs less. For example, in the example shown in FIG. 8, since the entry link from the node B to the target node A has already been determined, an exit link with a low passing cost can be formed from the entry link between the node A and the node D. The passing target link LKS to be connected is directed in the direction from the node A to the node B.

  The passing target link LKS that cannot be directed even when the directed rules described above are applied is directed in one direction without any particular reason.

  When the passing target link LKS is directed, the CPU 201 determines a one-to-one combination of the incoming link and the outgoing link, with the processing target node NDS having the same number of incoming links and the same number of outgoing links as the target node. Step S20).

  Here, the reason why all the passage target links LKS are directed in the previous step S10 will be described. FIGS. 9 and 10 are diagrams for explaining calculation when determining a one-to-one combination of an exit link and an ingress link for a link that is not directed (undirected link). In FIG. 9, a network representing a four-way path centering on the node of interest A is shown. Connection using the node of interest A, the link connected to the node of interest A, and nodes connected at different ends of the node of interest A (four nodes B, C, D, and E in FIG. 9) as elements. Links can be represented by matrices. In this connection matrix, for example, when the link between the node A and the node B is a directional link from the node A to the node B, the matrix (A, B) has a value at the position of the matrix (B, A). The position has no value (0). On the other hand, in the case of an undirected link between the node A and the node B, both the position of the matrix (A, B) and the position of the matrix (B, A) have values. If it has a value, that value is the number of links that exist between the nodes. Here, with regard to the link connected to the target node A in FIG. 9B, determining the combination of the approach link and the exit link means that the node as the entry source is the row component and the node as the exit destination is the column component. In the connection matrix, it is equivalent to ensuring that the total value of elements is only 1 regardless of whether the row or column is viewed. When this is processed as an undirected link, all the links are candidates for both the incoming link and the outgoing link. Therefore, the number of combinations is n × (n−, where n is the number of links connected to the node of interest. 1) As shown in FIG.

  The “n-queen problem” is known as a well-known problem similar to this combination problem. The n-queen problem is the problem of placing n queens on an nxn chess board so that no other queen is placed within the range of movement of the chess queen (infinite in the vertical, horizontal, and diagonal directions). is there. The problem of determining the combination of the approach link and the exit link in the present embodiment is the same as the problem of making the queen movable range infinite in the vertical and horizontal directions except for the diagonal direction from the queen movable range in the n queen problem. . The n-queen problem is known to have a large amount of calculation when the number of n exceeds 8. The problem of determining the combination of the incoming link and the outgoing link in the present embodiment is also difficult if the number of links connected to the node of interest exceeds eight, and it is difficult to determine the combination with a realistic calculation amount.

  FIG. 11 is a diagram for explaining calculation when determining a one-to-one combination of an exit link and an ingress link in the present embodiment. In this embodiment, since the link connected to the processing target node (target node) is previously directed, the number of combinations that must be considered can be greatly reduced. Specifically, the number of combinations obtained by halving the number of n described above is sufficient. For example, as shown in FIG. 11, when the number of links connected to the node of interest is 4, in the expression of the number of combinations n (n−1) that must be considered for undirected links, n = 4/2 It is only necessary to consider the number with = 2, that is, two ways. In this way, when the link connected to the target node is directed, n becomes eight, which means that the number of links connected to the target node becomes sixteen. When considering an intersection in the real world, the number of links connected to the node of interest is considered to be less than 16, even if links are added to match the number of exit links and ingress links, as will be described later.

  12 and 13 are diagrams for explaining determination of a one-to-one combination of an entrance link and an exit link. The combination of the approach link and the exit link is determined to comply with traffic regulations. For example, as shown in FIG. 12, when it is prohibited to go straight from the node D side to the node B and pass to the node B, as shown on the right side in FIG. And the exit link from the target node A to the node B are combined, and the entrance link from the node D to the target node A and the exit link from the target node A to the node C are combined.

  When traffic regulations are not violated, the combination of the entrance link and the exit link is determined so that the passing cost is low. Usually, the passing cost is often set as straight ahead <left turn <right turn <U turn, and according to this, the order of priority as a combination is 1. Straight ahead, 2. Turn left 3. Turn right, 4. Make a U-turn. For example, as shown in FIG. 13 (a), when there is no traffic restriction in the node A of interest, the combination pattern of the entrance link and the exit link is shown in FIG. 12 (b) and in FIG. 12 (c). There are two patterns. In this case, the pattern is determined as a pattern shown in FIG.

  The processing target node NDS whose combination is not uniquely determined even when the combination determination rule described above is applied is determined as one combination without any particular reason. If no combination using all the entry / exit links is found, even if the number of links for entry and exit is equal, step 30 is performed a plurality of times to determine at least one combination. If a combination cannot be obtained due to road restrictions or link configuration, the guide route may be cut there.

  Next, the CPU 201 adds a passing target link so that the number of connected incoming links and outgoing links is equal for the processing target node NDS where the number of incoming links and outgoing links to be connected is not equal (step S30). ). 14 and 15 are diagrams for explaining processing for adding a passage target link. In FIG. 14 and FIG. 15, an arrow indicated by a dashed line represents a passing target link LKS that has already been determined. In FIG. 14, the node A is an escape shortage node in which the number of exit links (links to the node D) is smaller than the number of incoming links (links from the node C and links from the node D) to be connected. An escape-deficient node needs to add an escape link in order to make the number of incoming links to be connected equal to the number of outgoing links. On the other hand, the node E is an inadequate entry node having a smaller number of incoming links (links from the node H) than the number of outgoing links (links to the node F and links to the node G). The under-entry node needs to add an ingress link in order to make the number of ingress links to be connected equal to the number of egress links. Here, the CPU 201 executes a route search with the escape insufficient node as the departure node candidate and the insufficient entry node as the destination node candidate among the processing target nodes NDS. As a result, when a connection route is obtained, the CPU 201 determines whether or not a set of an entrance link and an exit link is determined on both the departure node candidate and the destination node candidate on the obtained connection route. . In the example illustrated in FIG. 14, a connection route from the node A to the node E via the node I and the node J is searched. In node A, which is a departure node candidate, an exit link from node A to node I, which is a part of the newly obtained route, is added, so that the combination of the entrance link and the exit link can be determined. However, in the example shown in FIG. 14, even if an entry link from node J, which is a part of the newly obtained route, to node E is added to node E, which is a destination node candidate, entry is made due to traffic restrictions. The link and exit link pair cannot be determined. In this case, the passage target route to be added is not fixed.

  On the other hand, in the example shown in FIG. 15, node A is an inadequate entry node and node F is an inadequate exit node. In this case, the CPU 201 performs a route search using the node F as a departure node candidate and the node A as a destination node candidate. In the example illustrated in FIG. 15, a connection route from the node F to the node E via the node J and the node D is searched. In the example illustrated in FIG. 15, in the node F that is the departure node candidate, an exit link from the node F that is a part of the newly obtained route to the node J is added, so that the entrance link and the exit You can determine the link combination. In addition, in the example shown in FIG. 15, in the node A that is the destination node candidate, an entry link from the node D that is a part of the newly obtained route to the node A is added, so that the entry link and the exit are escaped. A set of links can be determined. In this case, the link constituting the obtained connection route is determined as the passing target link LKS to be added. Note that the searched connection path may be a link that has already been made the passage target link LKS or a link that is not the passage target link LKS. When a link constituting the connection path is added as the passage target link LKS, a virtual link is duplicated and added as a new passage target link LKS for the link that is already the passage target link LKS. The road corresponding to the link in which the copied passage target link LKS exists passes through the guide route a plurality of times. When the link constituting the connection path is added as the passage target link LKS, the link is added as the passage target link LKS for a link that is not the passage target link LKS.

  Thus, when the passage target link is added, the CPU 201 determines whether or not the combination of the approach link and the exit link is determined for all the processing target nodes NDS (step S40).

  When the CPU 201 determines that the combination of the approach link and the exit link has not been determined for all the processing target nodes NDS (step S40: NO), the CPU 201 returns to step S30 and exits from the approach link while adding the passage target link. The above-described processing for determining the link combination is repeated.

  On the other hand, when the CPU 201 determines that the combination of the entry link and the exit link is determined for all the processing target nodes NDS (step S40: YES), the CPU 201 determines the entry link and the exit link determined for each processing target node NDS. A one-stroke path is determined according to the combination (step S50). FIG. 16 is a diagram for explaining determination of a one-stroke path. In the upper diagram of FIG. 16, it is shown that the combination of the entry link and the exit link is determined for all the nodes. According to this combination, when a one-stroke path is drawn so as to pass through all the links once, a first one-stroke path indicated by a solid bold line and a second one indicated by a broken bold line as shown in the lower diagram of FIG. It can be seen that a one-stroke path is created. As described above, when a single stroke path is drawn so as to pass through all the links once, it does not necessarily become one single stroke path, and a plurality of single stroke paths may be created.

  The CPU 201 determines whether or not there is one single stroke writing path (step S60). As a result, if it is determined that there is only one stroke writing route (step S60: YES), the guidance route creation process is terminated with the one stroke writing route as the final guidance route.

  On the other hand, if the CPU 201 determines that there is not one stroke writing path (there is a plurality) (step S60: NO), the processing target node NDS that can change the combination of the entry link and the exit link so as to reduce the stroke writing path. The combination of the entry link and the exit link is changed (step S70).

  FIG. 17 is a diagram for explaining a change in the combination of the entry link and the exit link. In the example of FIG. 17, the combination of the entrance link and the exit link is changed for the node A. That is, in the node A before the change, the combination of the entry link from the node E to the node A and the exit link from the node A to the node C, the entry link from the node B to the node A, and the node A to the node D In the case of the combination of the exit links (FIG. 17: upper diagram), in the changed node A, the combination of the entrance link from the node E to the node A, the exit link from the node A to the node D, and the node B This is a combination of an incoming link to node A and an outgoing link from node A to node C (FIG. 17: lower diagram). As a result, it can be seen that the one-stroke path becomes two. Here, the CPU 201 does not change such a combination for a node that has only one combination pattern of the entry link and the exit link due to traffic restrictions. The CPU 201 searches for a node having a plurality of patterns of combination of the incoming link and the outgoing link, and changes such a combination with respect to a node having a plurality of patterns of the incoming link and the outgoing link. Note that when there are three or more combination patterns of entry links and exit links and a plurality of combinations can be changed, the CPU 201 changes the combination to the combination with the lower passage cost. As a result, the finally created guidance route guides a route that can efficiently pass through the road corresponding to the passage target link.

  When the combination of the entry link and the exit link is changed, it is determined again whether or not there is one stroke stroke path (step S60). As a result, if it is determined that there is only one stroke writing route (step S60: YES), the guidance route creation process is terminated with the one stroke writing route as the final guidance route. On the other hand, when the CPU 201 determines that there is not one (one or more) one-stroke path, the CPU 201 returns to step S70 and repeats the process of changing the combination of the incoming link and the outgoing link for another processing target node NDS again.

  Here, the Euler graph will be described. When all links are directed links, if the number of connected incoming links is equal to the number of outgoing links in all nodes, it always returns from one node to the same node and passes through all links once. It is known that a single stroke path (Euler cycle) can be created. In the present embodiment, since the combination of the approach link and the exit link is determined for all the processing target nodes NDS (for example, FIG. 16), the entrance links connected to the nodes for all the processing target nodes NDS. And the number of exit links are guaranteed to be equal. Therefore, if the change of the combination of the approach link and the exit link in step S70 is repeated, it is possible to create one single stroke route as a final guide route.

  According to the above-described embodiment, it is possible to reduce the calculation time for creating a guide route that passes through a route that passes through all the passage target links LKS. Specifically, for all nodes to be processed NDS, a combination of entry and exit links is determined and then a one-stroke guide route is created. Cycle) can be created. Furthermore, since the combination of the entrance link and the exit link is determined after all the routes to be passed are directed, the calculation time can be dramatically shortened. In addition, when determining the combination of the entry link and the exit link, determining the direction of passage of the route to be passed (directed), and changing the combination of the entrance link and the exit link so that a plurality of one-stroke paths are combined. Since the determination or change is made so that the passage cost is lowered in consideration of the passage cost, the total passage cost of the generated guide route can be reduced.

B. Modifications-First modification:
In the above-described embodiment, in step S10 (FIG. 4), the passing target link LKS that cannot be directed even when the above-described directed rule is applied is directed in one direction without any particular reason. However, instead of this, the passing target link LKS that could not be directed may be directed by applying the above-mentioned rules again after performing Step S30 and Step S40 (FIG. 4). An example thereof will be described with reference to FIG. 18 as a first modification. FIG. 18 is a flowchart showing process steps of the guide route creation process in the first modification. In the present modification, first, the CPU 201 directs the passage target link as much as possible according to traffic regulation, two-difference road connection, the difference between the approach link and the exit link, the passage cost, and the like (step S110). Next, the CPU 201 determines a set of entry and exit for nodes in which all the links to be connected are directed and the number of intrusions and exits is equal (step S120). Subsequently, the CPU 201 obtains a route that makes the difference small for all the directed links to be connected, for the nodes where the numbers of ingress and egress are not equal (step S130). If there is an undirected link corresponding to the obtained route, the CPU 201 directs it in the same direction as the route, and if not, adds a new link (step S140). Thereafter, the CPU 201 determines whether a set of entry and exit has been determined in all nodes (step S150). If the entry / exit pair has been determined for all nodes (step S150: YES), the CPU 201 proceeds to the process of step S160. CPU201 returns to above-mentioned step S110, and repeats the process to step S110-S140, when the group of approach and escape is not determined by all the nodes (step S150: NO). In step S160, a one-stroke path is determined in the same manner as in step S50 (FIG. 4) in the embodiment (step S160). Next, the CPU 201 determines whether or not there is only one stroke writing path as in step S60 in the embodiment (step S170). When there is only one stroke writing path (step S170: YES), the CPU 201 ends the determination process. When there are a plurality of one-stroke paths (step S170: NO), the CPU 201 changes the entry / exit set to reduce the one-stroke path as in step S70 (FIG. 4) in the embodiment (step S180). The processes of step S170 and step S180 are repeated until there is one stroke writing path. Also in the first modified example described above, a guide route that finally passes through all the passage target links can be created in a short calculation time as in the embodiment.

・ Second modification:
In the above embodiment, the number of exit links and the number of ingress links are made equal for all processing target nodes NDS. By deleting the part, one exit link may be reduced for one of the processing target nodes NDS, and one ingress link may be decreased for the other one. By doing this, it is possible to create a one-stroke guide route (Euler route) from a node having one escape link to a node having one entry link.

・ Third modification:
In the above embodiment, all the guidance route creation processing is realized by software, but part or all of the guidance route creation processing may be realized by hardware.

  As mentioned above, although the Example and modification of this invention were demonstrated, this invention is not limited to these Example and modification at all, and implementation in a various aspect is possible within the range which does not deviate from the summary. It is.

200 ... Guide route creation device 201 ... CPU
202 ... Input / output unit 203 ... Internal storage device 204 ... External storage device D11 ... Map data M11 ... Pass target link recognition unit M12 ... Process target node recognition unit M13 ... Link directed processing unit M14 ... Entry / exit decision unit M15 ... Route Guide creation department

Claims (11)

A guide route creation device,
A network storage unit for storing road network data including a plurality of nodes and links connecting the nodes;
Among the links included in the road network, a passage target link recognition unit that recognizes a link corresponding to a road to be passed as a passage target link;
A processing target node recognition unit that recognizes all nodes connected to the plurality of passing target links as processing target nodes among the nodes included in the road network;
A directing processing unit that determines a passing direction according to a predetermined condition for all the passing target links,
For a target node that is one of the processing target nodes, a one-to-one combination of an incoming link that enters the target node and an outgoing link that exits the target node is determined according to the passing direction of the target link. An entry / exit decision unit that executes an entry / exit decision process using all the processing target nodes as the target node;
Based on the determined combination of the entry link and the exit link, a guidance route creation unit that creates a guidance route that passes through all the passage target links;
A guide route creation device comprising: The guide route creation device according to claim 1,
When the number of the plurality of passage target links connected to the node of interest is an odd number, the entry / exit determination unit replicates one of the plurality of passage target links and virtually By adding the passable link as the passable link by adding it as a passable link, or by adding the passable link among the links that are not passable, according to the pass direction of the passable link, the A guide route creation device that determines a one-to-one combination of an entrance link and the exit link. The guide route creation device according to claim 1 ,
The predetermined route includes a guide route generation device including observing traffic regulations . A guide route creation device according to any one of claims 1 to 3 ,
The predetermined condition in the directed processing unit includes a guide route generation device including reducing a difference between the number of the incoming links and the number of the outgoing links of the node of interest . A guide route creation device according to any one of claims 1 to 4 ,
The predetermined condition includes a guide route generation device including reducing a passing cost when passing through the node of interest . A guiding route generation device according to any one of claims 1 to 5,
The entry / exit determination unit is a guide route generation device that determines a one-to-one combination of the entry link and the exit link so as to reduce a passing cost when passing through the node of interest . A guide route creation device according to any one of claims 1 to 6,
The entry / exit decision unit
Among the nodes to be processed, an exit shortage node having a number of exit links that is less than the number of the incoming links is set as a departure node, and among the nodes to be processed, the number of entrance links is less than the number of the exit links. Search for additional routes with the missing node as the destination node,
By adding a link corresponding to the additional route to the passage target link, the number of the incoming links and the number of the outgoing links are made equal for each processing target node,
A guide route creation device that determines a one-to-one combination of the entry link and the exit link . A guide route creation device according to any one of claims 1 to 6 ,
The guide route creation unit creates a single stroke route according to a combination of the entry link and the exit link,
When a plurality of one-stroke paths are created, the combination pattern of the entry link and the exit link is changed for the processing target node in which a plurality of combinations of the entry link and the exit link are allowed. Thus, a guide route creating apparatus that connects a plurality of one-stroke paths and finally creates the guide route consisting of one one-stroke path . The guide route creation device according to claim 8 ,
The entry / exit determination unit changes the combination pattern of the entry link and the exit link to a pattern having the lowest passage cost when three or more combinations of the entry link and the exit link are allowed. Guide route creation device. A guide route creation method for creating a guide route using a computer,
  The computer includes a network storage unit that stores road network data including a plurality of nodes and links connecting the nodes,
  The guide route creation method is:
(A) the computing means of the computer recognizing a link corresponding to a road to be passed among the links included in the road network as a passage target link;
(B) a step of recognizing all nodes connected to the plurality of passage target links among the nodes included in the road network as processing target nodes;
(C) a step of determining a passing direction according to a predetermined condition for all of the passing target links;
(D) For the link including at least the passage target link connected to the attention node that is one of the processing target nodes, the computing means of the computer, according to the passing direction of the passage target link, the attention node Determining a one-to-one combination of an entry link that enters an exit link and an exit link that exits from the node of interest, and executing all the processing target nodes as the node of interest;
(E) creating a guide route that passes through all the passage target links based on the determined combination of the approach link and the exit link;
  A guide route creation method comprising: A computer program for causing a computer to create a guide route,
  A network data acquisition function for acquiring road network data including a plurality of nodes and a link connecting the nodes;
  Among the links included in the road network, a passing target link recognition function for recognizing a link corresponding to a road to be passed as a passing target link;
  A processing node recognition function for recognizing all nodes connected to the plurality of passing links among the nodes included in the road network as processing nodes;
  A step of determining a passing direction according to a predetermined condition for all of the passing target links;
  For the link including at least the passing target link connected to the target node that is one of the processing target nodes, according to the passing direction of the passing target link, the incoming link that enters the target node and the target node Determining the one-to-one combination of exit links to exit, entering and exiting determination function for executing all the processing target nodes as the target nodes;
  Based on the determined combination of the approach link and the exit link, a guide route creation function for creating a guide route that passes through all of the passage target links;
  A computer program for causing the computer to realize the above.

Images