Route searching device, route searching method, and computer program

Abstract

To provide a route searching device that can suppress a guidance of routes including a blind alley or a dead end.SOLUTION: A route searching device comprises: a route information storage unit that stores road network data including information on a node, and information on a link linking between the nodes; and a route searching unit that searches for routes from a departure site to a destination site. The route searching unit is configured to, after excluding, from a search object, a terminal link serving as the link in which only one is connected to other link of the nodes located at either end of the link, search for routes from the road network data and cause the searched routes to output.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a route search device, a route search method, and a computer program. [Background technology]

[0002] Navigation devices that provide route guidance from a departure point to a destination are known. Such navigation devices are often installed in vehicles and used to provide route guidance for the vehicle, so there is a demand for them to avoid searching for routes that include dead ends or cul-de-sacs that require the vehicle to make a U-turn.

[0003] In this regard, for example, Patent Document 1 discloses that when a navigation device receives first information indicating a dead end within or beyond a predetermined section, the predetermined section is excluded from the selection settings for a driving route, thereby preventing the device from searching for routes that cannot be used as a driving route. For example, Patent Document 2 discloses that when a navigation device is set with a guide route that makes a U-turn at the end of a dead end, it displays a U-turn guidance image. For example, Patent Document 3 discloses that when a car navigation device determines that a road is a dead end, it provides guidance regarding the dead end road. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-18958 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-243187 [Patent Document 3] Japanese Patent Application Laid-Open No. 2006-220562 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, in recent years, the spread of internet shopping has led to an increase in demand for logistics services, and an increase in the number of people (hereinafter also referred to as "delivery persons") engaged in the task of delivering packages such as merchandise to designated destinations. From the perspective of improving work efficiency, delivery persons are assigned a predetermined area of ​​responsibility, and deliver packages to residential homes within that area. Compared to normal main roads, areas with many residential homes tend to have more cul-de-sacs and dead ends where vehicles have to make U-turns, as well as more traffic of people and bicycles. For this reason, there is a particular need for route search devices (navigation devices) used in delivery services to suppress guidance of routes that include cul-de-sacs and dead ends.

[0006] In this regard, the navigation device described in Patent Document 1 uses the first information to determine whether a route is a dead end, and therefore has the problem of guiding routes that include dead ends or cul-de-sacs in locations where the first information is not available. In particular, residential areas with many private homes tend to be slower to provide information than business districts. In delivery operations, however, it is even more important from the perspective of demand and safety to suppress guidance on routes (routes that include dead ends or cul-de-sacs) in such residential areas. Furthermore, the navigation devices described in Patent Documents 2 and 3 only provide information on U-turns and cul-de-sac roads, and do not consider suppressing guidance on routes that include dead ends or cul-de-sacs. As mentioned above, this problem is not limited to route search devices used in delivery operations, but is also a common problem for route search devices for general users.

[0007] For this reason, there has been a demand for a route search device that can suppress guidance on routes that include dead ends or cul-de-sacs. [Means for solving the problem]

[0008] The present invention has been made to solve at least part of the above-mentioned problems, and can be realized in the following aspects.

[0009] (1) According to one aspect of the present invention, there is provided a route search device comprising: a route information storage unit that stores road network data including information on nodes and information on links connecting the nodes; and a route search unit that searches for a route from a departure point to a destination, wherein the route search unit searches for the route from the road network data while excluding terminal links, which are links in which only one of the nodes located at both ends of a link is connected to another link, and outputs the searched route.

[0010] A "dead end" refers to a road where only one of the ends of the road is connected to another road. According to this configuration, the route search unit searches for a route after excluding terminal links (i.e., links that correspond to dead ends) from the road network data, which are links where only one of the nodes located at both ends of the link is connected to another link. This makes it possible to provide a route search device that can suppress guidance of routes that include dead ends. Furthermore, according to this configuration, the determination of whether a link is a terminal link (a link that corresponds to a dead end) is made using the link connection relationships in the road network data used for route search. Therefore, compared to when special information is required separately, guidance of routes that include dead ends can be suppressed without being affected by whether information is available or not.

[0011] (2) In the route search device of the above form, the route search unit may search for the route from the road network data, in addition to the terminal link, by excluding from the search target a specific link in which one of the nodes located at both ends of the link is connected only to the terminal link. A "cul-de-sac" refers to a group of roads that are shaped like a dead end and cannot be passed through. According to this configuration, the route search unit searches for a route by excluding from the search target, in addition to terminal links, specific links (i.e., links leading to a dead end) in which one of the nodes located at both ends of the link is connected only to the terminal link, from the road network data. This makes it possible to provide a route search device that can suppress guidance of routes that include dead ends. Furthermore, according to this configuration, whether a link is a specific link (a link leading to a dead end) is determined using the link connection relationships in the road network data used for route search. Therefore, compared to when special information is required separately, guidance of routes that include dead ends can be suppressed without being affected by whether information is available.

[0012] (3) In the route search device of the above form, the route search unit searches for a route from the departure point to the destination via a predetermined intermediate point, and when a node located at both ends of the terminal link that is not connected to any other link is set as an end node, if the link length from the end node to the intermediate point is equal to or greater than a predetermined threshold, the terminal link may be searched for the route without being excluded from the search. In cases where the road length is long even if it is a dead end, there is a demand for guidance on a route that includes the dead end. In this regard, according to this configuration, when a node that is not connected to any other link among the nodes located at both ends of a terminal link is set as an end node, if the link length from the end node to the intermediate point is equal to or greater than a predetermined threshold, the route search unit does not exclude the terminal link (link that corresponds to a dead end) from the search. Therefore, in cases where the road length is long even if it is a dead end, the route search unit can provide guidance on a route that includes the dead end.

[0013] (4) In the route search device of the above form, if the terminal link is a link facing either the departure point or the destination, the route search unit may search for the route without excluding the terminal link from the search target. Even if a link is a dead end, if it faces either the departure point or the destination, there is a demand for guidance on a route that includes the dead end. In this regard, according to this configuration, if an end link is a link that faces either the departure point or the destination, the route search unit does not exclude the end link (a link that corresponds to a dead end) from the search. Therefore, even if a link is a dead end, if it faces either the departure point or the destination, the route search unit can provide guidance on a route that includes the dead end.

[0014] (5) In the route search device of the above form, if the searched route includes a route that makes a U-turn around a certain link, the route search unit may exclude the links that make up the U-turn route from the search targets, re-search for the route, and output the re-searched route. Compared to normal main roads, residential areas with many private homes have many narrow roads where vehicles make U-turns, and there is a lot of traffic, including pedestrians and bicycles. In this regard, according to this configuration, if the searched route includes a route that makes a U-turn at a certain link, the route search unit excludes the links that make up the U-turn route from the search targets, searches for the route again, and outputs the re-searched route. As a result, the route search device of this configuration further suppresses guidance for routes that include U-turn routes, thereby improving ease of travel on the guided route and improving safety.

[0015] (6) In the route search device of the above form, the route search unit may obtain information on one or more delivery destinations where a user of the route search device will stop for the delivery of a package, and search for the route from the departure point to the destination via the one or more delivery destinations as intermediate points. In recent years, the spread of internet shopping has led to an increase in demand for logistics services, and an increase in the number of people (delivery personnel) engaged in the task of delivering packages such as merchandise to designated destinations. In this regard, according to the present configuration, the route search unit acquires information on one or more delivery destinations where the user (delivery personnel) of the route search device will stop to deliver the package, and searches for a route from the departure point to the destination via one or more delivery destinations as intermediate points, thereby providing a route search device specialized for delivery services.

[0016] (7) In the route search device of the above form, the route search unit may acquire location information of parking spaces that are located near roads and where a vehicle can be safely parked, and that are located along the searched route, and may output the acquired location information of the parking spaces in addition to the searched route. In residential areas where many private homes are located, there are fewer parking spaces than near normal main streets. In this regard, with this configuration, the route search unit acquires location information of parking spaces (parking spaces where a vehicle can be safely parked) along the searched route and outputs the location information of the parking spaces along with the searched route. This prevents users (delivery people) from parking their vehicles on unsafe roadsides in residential areas where there are few parking spaces, thereby improving convenience and safety for users.

[0017] The present invention can be realized in various forms, for example, in the form of a route search device, a navigation device, a navigation system, a computer program for realizing the functions of these devices and systems, a server device for distributing the computer program, a non-transitory storage medium on which the computer program is stored, etc. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a diagram showing a schematic configuration of a navigation system according to an embodiment of the present invention; [Figure 2] FIG. 10 is a diagram illustrating an example of delivery plan information. [Figure 3] 10 is a flowchart illustrating an example of a processing procedure for a route search process. [Figure 4] FIG. 10 is a diagram illustrating a specific example of rule a1. [Figure 5] FIG. 10 is a diagram illustrating a specific example of rule a2. [Figure 6] FIG. 10 is a diagram illustrating a specific example of rule a3. [Figure 7] FIG. 10 is a diagram illustrating specific examples of rules a4 and a5. [Figure 8] FIG. 10 is a diagram illustrating a specific example of an exclusion target route. [Figure 9] FIG. 10 is a diagram illustrating an example of a guide screen displayed on a client. [Figure 10] FIG. 10 is a diagram showing a schematic configuration of a navigation system according to a second embodiment. [Figure 11] 10 is a flowchart illustrating an example of a processing procedure for a route search process according to the second embodiment. [Figure 12] FIG. 10 is a diagram showing a schematic configuration of a navigation system according to a third embodiment. [Figure 13] FIG. 10 is a diagram showing a schematic configuration of a navigation system according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] A. First embodiment: Fig. 1 is a diagram showing the schematic configuration of a navigation system 1 according to one embodiment of the present invention. The navigation system 1 is a system whose users are people (hereinafter also referred to as "delivery persons") who are engaged in logistics work, particularly the work of delivering packages such as merchandise to designated destinations. The navigation system 1 illustrated here outputs guidance information to the users (delivery persons) including route guidance to the destination of the package to be delivered (hereinafter also referred to as "package to be delivered") and information related to the destination, thereby facilitating delivery work.

[0020] The navigation system 1 of this embodiment can suppress guidance of routes that include dead ends or cul-de-sacs through a route search process described below. Here, a "dead end" refers to a road where only one of its ends is connected to another road. Also, a "cul-de-sac" refers to a group of roads that are shaped like a dead end and cannot be passed through.

[0021] The navigation system 1 includes a server 10 and a client 30. The server 10 is connected to the Internet INT by wired communication. The client 30 is connected to the Internet INT by wireless communication via a communication carrier BS. The communication carrier BS includes a transmitting / receiving antenna, a wireless base station, and a switching center. In other words, the server 10 and the client 30 can communicate with each other via the Internet INT.

[0022] The server 10 uses delivery plan information 341 (details of which will be described later) acquired from the client 30 to search for a route (hereinafter also referred to as a "delivery route") in which the delivery destination addresses of packages requiring delivery are set as stopover points. The server 10 corresponds to a "route search device." The server 10 includes a CPU 110, a communication unit 120, a ROM / RAM 130, and a storage unit 140, and each unit is interconnected by a bus (not shown).

[0023] The CPU 110 controls each unit of the server 10 by loading a computer program stored in the ROM 130 into the RAM 130 and executing it. The CPU 110 also functions as a route search unit 111. The route search unit 111 is a processing unit that searches for a route from a departure point to a destination using a route information DB 142. The route search unit 111 of this embodiment calculates the delivery route described above. The communication unit 120 controls communication with other devices such as the client 30 via a communication interface (not shown).

[0024] The storage unit 140 is configured with a hard disk, a flash memory, a memory card, etc. The storage unit 140 pre-stores a map information database 141, a route information database 142, and a guidance information database 143. In the following description, the databases will also be simply referred to as "DBs."

[0025] The map information DB 141 is a database that stores data representing map images. The data representing map images includes information necessary for map display, such as topography, buildings, and road shapes. The route information DB 142 is a database that stores road network data. The road network data includes node information on "nodes" that represent the locations of intersections and landmarks such as stations, and link information on "links" that represent roads connecting the nodes. The node information includes node location information, node type, node name, other node information, etc. The link information includes link costs for each mode of transportation (average travel time for the road represented by the link), link type, link name, link status, other link information, etc. The route information DB 142 corresponds to a "route information storage unit."

[0026] The guidance information DB 143 is a database that stores information about parking spaces. Here, a "parking space" refers to a place located near a road where a vehicle can be safely parked. The parking space in this embodiment is not limited to a so-called parking lot. Information about the parking space may include the location information of the parking space, as well as the type of parking space (whether it is a parking lot or not), the size of the parking space, the time period during which the parking space is available, and the like. The guidance information DB 143 may be stored in a server other than the server 10. In this case, the server 10 may connect to the other server as needed in the process described below to obtain information about the parking space.

[0027] The client 30 can be configured as any device, such as a smartphone as shown in the figure, a personal computer, an in-vehicle device, a wearable device, etc. The client 30 includes a CPU 310, a communication unit 320, a ROM / RAM 330, a storage unit 340, an input / output unit 350, and a current position acquisition unit 360, and each unit is connected to each other by a bus (not shown).

[0028] The CPU 310 controls each unit of the client 30 by loading a computer program stored in the ROM 330 into the RAM 330 and executing it, and also functions as a guidance unit 311. The guidance unit 311 transmits delivery plan information 341 to the server 10 and acquires delivery route information 342 from the server 10. The guidance unit 311 uses the acquired delivery route information 342 to output a delivery route (path) from the input / output unit 350, thereby providing guidance about the delivery route to the user of the client 30.

[0029] The communication unit 320 controls communication with other devices such as the server 10 via a communication interface (not shown).

[0030] The storage unit 340 is composed of a hard disk, a flash memory, a memory card, etc. The storage unit 340 pre-stores delivery plan information 341. The storage unit 340 also stores delivery route information 342 acquired from the server 10 through a process described below.

[0031] FIG. 2 is a diagram showing an example of delivery plan information 341. The delivery plan information 341 stores information on parcels to be delivered that day by the user of client 30 (hereinafter also referred to as "parcel information"). As shown in the figure, each parcel information includes, for example, the delivery address, the latitude and longitude of the delivery destination, whether or not there is a delivery box at the delivery destination, nameplate information, remarks information, a specified delivery time for the parcel, whether or not a delivery box is available, and drop-off / delivery information. The drop-off / delivery information may include whether or not drop-off / delivery is possible, a specified drop-off / delivery location, and specified conditions for drop-off / delivery (date, time, weather, etc.). Note that the parcel information may also include other information not shown.

[0032] Returning to FIG. 1, the explanation will be continued. The input / output unit 350 is a variety of interfaces used for inputting and outputting information between the client 30 and the user. For example, the input / output unit 350 may be a touch panel as an input unit, a touch panel as a display unit (output unit), or a liquid crystal panel. The current position acquisition unit 360 receives radio waves transmitted from artificial satellites constituting the GPS (Global Positioning System) or QZSS (Quasi-Zenith Satellite System), and acquires current position information (latitude and longitude) indicating the current position of the client 30. Here, since the client 30 is carried by the user, the current position acquired by the current position acquisition unit 360 can be considered the same as the current position of the user.

[0033] 3 is a flowchart showing an example of the processing procedure of the route search process. The route search process is a process executed by the server 10 to search for a delivery route. The route search process is started in response to a processing request from the client 30. The processing request from the client 30 includes the delivery plan information 341 described in FIG. 2. In step S100, the route search unit 111 acquires the delivery plan information 341 included in the processing request from the client 30.

[0034] In step S102, the route search unit 111 refers to the delivery plan information 341 acquired in step S100 and performs a route search in which each delivery destination address of package information 1 to n (n is any natural number) is set as a stopover point. The departure point at this time may be the current location acquired by the current location acquisition unit 360, or may be a predetermined location (for example, the user's home, a delivery business office, etc.). The arrival point can be a predetermined location (for example, the user's home, a delivery business office, etc.). The route search can be performed using the route information DB 142 and the well-known Dijkstra algorithm or the well-known A-star search algorithm.

[0035] Here, in step S102, the route search unit 111 excludes terminal links and specific links from the search in accordance with the following rules a1 to a5. Specifically, the route search unit 111 excludes terminal links and specific links from the search by performing processing such as assigning a maximum cost to the links in the route information DB 142 that correspond to terminal links and specific links, correcting the link cost so that the links are excluded from selection, or assigning a specific flag (hereinafter also referred to as "exclusion processing"). Here, an "terminal link" is a link that corresponds to a dead end (a road where only one of the two ends of the road is connected to another road). Also, a "specific link" is a link that leads to a dead end (a group of roads that form a closed lane and cannot be passed through).

[0036] (a1) The route searching unit 111 regards a link in which only one of the nodes located at both ends of the link is connected to another link as a "terminal link" and excludes it from the search target. (a2) The route searching unit 111 determines that a link in which one of the nodes located at both ends of the link is connected only to the terminal link of rule a1 is a "specific link" and excludes it from the search target. (a3) Even if a link corresponds to a terminal link of rule a1, if the link length from a node (end node) that is not connected to any other link among the nodes located at both ends of the terminal link to the intermediate point is equal to or greater than a predetermined threshold, the route search unit 111 does not exclude the terminal link from the search. (a4) Even if a link corresponds to an end link of rule a1, if the end link faces either the departure point or the destination, the route searching unit 111 does not exclude the end link from the search target. (a5) When all links correspond to the terminal links of rule a1 or the specific links of rule a2, the route searching unit 111 does not exclude the terminal links and the specific links from the search targets.

[0037] FIG. 4 is a diagram illustrating a specific example of rule a1. FIG. 4(A) shows an example of a searched route RT before the exclusion process. FIG. 4(B) shows an example of a searched route RTa after the exclusion process. Note that nodes with diagonal hatching in FIG. 4 indicate nodes (end nodes) that are not connected to other links. This also applies to FIG. 4 and subsequent figures. As shown in FIG. 4(A), assume that a waypoint WP is set on link EL. In link EL, only one of nodes N2 and N3 located at both ends of link EL (node ​​N2) is connected to another link. In such a case, the route search unit 111 determines that link EL is an end link in accordance with rule a1, and performs exclusion processing on link EL to exclude link EL from the search target. As a result, a route RTa that does not include link EL is calculated, as shown in FIG. 4(B). Route RTa is a route that does not include a U-turn on link EL (see route RT before the exclusion process). In addition, as shown in FIG. 4(B), the route search unit 111 may move the symbol display position of the waypoint WP to a position on the route RTa that is closest to the original position of the waypoint WP (waypoint WPa).

[0038] FIG. 5 is a diagram illustrating a specific example of rule a2. FIG. 5(A) shows an example of a searched route RT before exclusion processing. FIG. 5(B) shows an example of a searched route RTa after exclusion processing. As shown in FIG. 5(A), assume that a waypoint WP is set on link L1, and link L1 is connected to links EL1 and EL2 via node N3. Link EL1 is connected to another link only at one of nodes N3 and N5 located at both ends of link EL1 (node ​​N3). Similarly, link EL2 is connected to another link only at one of nodes N3 and N6 located at both ends of link EL2 (node ​​N3). Therefore, in accordance with rule a1, the route search unit 111 determines that links EL1 and EL2 are terminal links and performs exclusion processing on links EL1 and EL2, thereby excluding links EL1 and EL2 from the search targets. Furthermore, one of the nodes N2 and N3 located at both ends of link L1 (node ​​N3) is connected only to the terminal links (EL1 and EL2) of rule a1. Therefore, the route search unit 111 determines that link L1 corresponds to a specific link in accordance with rule a2, and performs an exclusion process on link L1, thereby excluding link L1 from the search targets. As a result, as shown in FIG. 5(B), a route RTa is calculated that does not include links L1, EL1, and EL2. This route does not include a U-turn on link L1 (see route RT before the exclusion process). Note that the route search unit 111 may move the symbol display position of the waypoint WP (waypoint WPa), as in FIG. 4.

[0039] FIG. 6 is a diagram illustrating a specific example of rule a3. FIG. 6(A) is a diagram illustrating a specific example of rule a3. The link connections and intermediate points in FIG. 6(A) are the same as those in FIG. 5. However, in FIG. 6(A), the link length of link EL1 is longer than that in the example in FIG. 5. As described in FIG. 5, link EL1 corresponds to a terminal link. Of nodes N3 and N5 located at both ends of link EL1, node N5 that is not connected to any other link is called the "end node." For link EL1, the link length A1 from the end node N5 to the intermediate point WP is equal to or greater than a predetermined threshold X1. Therefore, in accordance with rule a3, the route search unit 111 does not perform exclusion processing on link EL1 and does not exclude it from the search target (i.e., treats link EL1 as a link that does not satisfy rule a1). The threshold X1 can be set arbitrarily and may be registered or changed by the user of client 30. Furthermore, since link L1 does not fall under the category of a link (specific link) in which one of nodes N2 and N3 located at both ends of link L1 is connected only to the terminal link of rule a1, it is not subjected to exclusion processing and is not excluded from the search.

[0040] 6(B) is a diagram illustrating rules that may be executed in addition to rule a3. In addition to the above-mentioned rules a1 to a5, the route search unit 111 may determine links that are not subject to search in accordance with the following rule a31. (a31) The route search unit 111 does not exclude a specific link from the search even if the link corresponds to the specific link of rule a2 if the link length from a node (entrance node) located at both ends of the specific link that is different from the node connected to the terminal link to the intermediate point is equal to or greater than a predetermined threshold.

[0041] The link connections and intermediate points in FIG. 6(B) are the same as those in FIG. 5. However, in FIG. 6(B), the link length of link L1 is longer than that in the example in FIG. 5. As described in FIG. 5, link L1 corresponds to a specific link, and links EL1 and EL2 correspond to terminal links. Of the nodes N2 and N3 located at both ends of link L1, the node N2 other than node N3 connected to terminal links EL1 and EL2 is called the "entrance node." The link length B1 of link L1 from the entry node N2 to the intermediate point WP is equal to or greater than a predetermined threshold Y1. Therefore, in accordance with rule a31, the route search unit 111 does not perform exclusion processing on link L1 and does not exclude it from the search target (i.e., treats link L1 as a link that does not correspond to rule a2). The threshold Y1 can be set arbitrarily and may be registered or changed by the user of client 30. The threshold Y1 may be the same value as threshold X1 in FIG. 6(A).

[0042] The route search unit 111 may determine links not to be searched in accordance with the following rules b3 and b31 instead of the above-described rules a3 and a31. (b3) Even if a link corresponds to an end link of rule a1, if the link length of the end link (i.e., the link length stored in the route information DB 142) is equal to or greater than a predetermined threshold, the route search unit 111 does not exclude the end link from the search. (b31) Even if a link corresponds to a specific link of rule a2, if the link length of the specific link (i.e., the link length stored in the route information DB 142) is equal to or greater than a predetermined threshold, the route search unit 111 does not exclude the specific link from the search.

[0043] The route searching unit 111 may determine links not to be searched in accordance with the following rules c3 and c31 instead of the above-described rules a3 and a31. (c3) Even if a link corresponds to a terminal link of rule a1, if the end node of the terminal link is not included within a predetermined area from a predetermined position, the route searching unit 111 does not exclude the terminal link from the search target. (c31) Even if a link corresponds to the specific link of rule a2, if the entry node of the specific link is not included within a predetermined area from a predetermined position, the route searching unit 111 does not exclude the specific link from the search target. The predetermined position of rules c3 and c31 can be determined arbitrarily, and can be, for example, the position of the waypoint WP, the node N3 closest to the waypoint WP, etc. The predetermined area of ​​rules c3 and c31 means an arbitrary range defined around the predetermined position, and can be, for example, a criterion such as the inside of a virtual circle having a predetermined radius and centered on the predetermined position.

[0044] FIG. 7 is a diagram illustrating specific examples of rules a4 and a5. FIG. 7(A) shows a specific example of rule a4. The link connection relationships in FIG. 7(A) are the same as those in FIG. 4, but in FIG. 7(A), destination G is set on link EL. As explained in FIG. 4, link EL corresponds to an end link. Link EL is a link facing either the departure point or the destination (destination G in the illustrated example). Therefore, in accordance with rule a4, the route search unit 111 does not perform exclusion processing on link EL and does not exclude link EL from the search target (i.e., it treats link EL1 as a link that does not fall under rule a1). As a result, in the example of FIG. 7(A), a route RT leading to destination G on link EL is calculated.

[0045] FIG. 7B shows a specific example of rule a5. The link connections and route points in FIG. 7B are the same as those in FIG. 5, but in FIG. 7B, in addition to nodes N5 and N6, nodes N1 and N4 also correspond to end nodes. Also, in FIG. 7B, destination G is set on link EL3. Link EL3 is a terminal link in which only one (node ​​N2) of nodes N1 and N2 located at both ends of link EL3 is connected to another link. Similarly, link EL4 is a terminal link in which only one (node ​​N2) of nodes N2 and N4 located at both ends of link EL4 is connected to another link. Therefore, in accordance with rule a5, the route search unit 111 does not perform exclusion processing on terminal links EL1, EL2, EL3, and EL4 and specific link L1, and does not exclude them from search targets (i.e., links EL1, EL2, EL3, and EL4 are treated as links that do not fall under rule a1, and link L1 is treated as a link that does not fall under rule a2). As a result, a route RT including a U-turn on link L1 is calculated as shown in FIG. 7(B).

[0046] The route searching unit 111 does not apply rules a1 to a5 to links that are not terminal links in terms of the link connections but are impassable due to road closures, restrictions, or the like.

[0047] In step S104 of FIG. 3, the route search unit 111 determines whether or not the route obtained in step S102 includes an exclusion target route. Here, the "exclusion target route" can be arbitrarily defined; for example, a U-turn route can be set as the exclusion target route. In this case, the route search unit 111 analyzes the route (link sequence) obtained in step S102, and can determine that a U-turn route is included if the route includes a round trip on the same link (specifically, if the route includes forward travel on link A and reverse travel on link A). If the route to be excluded is included (step S104: YES), the route search unit 111 transitions the process to step S106. On the other hand, if the route to be excluded is not included (step S104: NO), the route search unit 111 transitions the process to step S108.

[0048] FIG. 8 is a diagram illustrating a specific example of a route to be excluded. Assume that the route RT shown in FIG. 8 is calculated as a result of the route search in step S102. In this case, the route search unit 111 determines that a U-turn route is included in the route RT. Note that in step S104, the route search unit 111 may determine the route to be excluded by taking into account the link width (road width). For example, if the link width is larger than a predetermined value, the route search unit 111 may determine that the route is a main road where a U-turn is possible, and may determine that the route to be excluded is not included (step S104: NO). The predetermined value that serves as this criterion can be determined arbitrarily.

[0049] In step S106, the route search unit 111 performs an exclusion process on the links that make up the route to be excluded, thereby excluding the links that make up the route to be excluded from the search targets. Thereafter, the route search unit 111 performs a route search again, and transitions the process to step S108.

[0050] In step S108, the route search unit 111 generates delivery route information and transmits it to the client 30, thereby outputting it. Specifically, the route search unit 111 searches the guidance information DB 143 and obtains information about parking spaces along the route (delivery route) searched for in step S102 or step S104 (such as location information for the parking space, the type of parking space, the size of the parking space, and the time period during which the parking space is available). The route search unit 111 then transmits the route searched for in step S102 or step S104 and the obtained information about the parking spaces as "delivery route information" to the client 30. Note that the phrase "step S102 or step S104" means that if a re-search is performed in step S104, the search result in step S104 is used, and if a re-search is not performed in step S104, the search result in step S102 is used.

[0051] 9 is a diagram showing an example of a guidance screen W1 displayed on the client 30. After acquiring delivery route information from the server 10, the guidance unit 311 of the client 30 outputs a screen W1 for providing delivery route guidance to the input / output unit 350. As shown in FIG. 9, the screen W1 includes a map view V1, a delivery destination list view V2, and a guidance view V3.

[0052] The map view V1 displays a map. The map displays the current location symbol PL, the delivery route RT, a delivery destination symbol S1 plotted at the first delivery destination, a delivery destination symbol S2 plotted at the second delivery destination, and symbols PS1 to PS3 representing the locations of parking spaces along the delivery route RT. As shown in the map view V1 of FIG. 9, the first delivery destination S1 is located on an end link. However, as a result of the route search process described in FIG. 3 suppressing the calculation of routes that include dead ends, the delivery route RT does not include the end link facing the delivery destination S1. When the user taps on one of the parking spaces PS1 to PS3, the guidance unit 311 may display detailed information about the tapped parking space (e.g., the type of parking space, the size of the parking space, the time period during which the parking space is available, etc.) in any manner, such as a speech bubble or a separate window. Note that the parking space PS3 is located slightly away from the delivery route RT. In this way, the route search unit 111 may add information about parking spaces around the delivery route RT to the delivery route information in addition to information about parking spaces along the delivery route RT (FIG. 3: step S108).

[0053] The delivery destination list view V2 displays package information about packages requiring delivery (such as the delivery destination address, the latitude and longitude of the delivery destination, the presence or absence of a delivery box at the delivery destination, nameplate information, remarks, specified delivery time, availability of a delivery box, and drop-off information) in list form. The guidance view V3 displays the estimated time of arrival at the first stopover point (i.e., the first delivery destination S1) and the distance from the current location PL to the first delivery destination S1. Note that the screen W1 shown in FIG. 9 is merely an example and various modifications are possible. For example, the delivery destination list view V2 and the guidance view V3 may be omitted. In this case, for example, when the user taps on a delivery destination S1 or S2, package information about packages requiring delivery for the tapped delivery destination may be displayed in any manner, such as in a speech bubble or in a separate window. For example, the estimated time of arrival at the first delivery destination S1 and the distance from the current location PL to the first delivery destination S1 may be output by voice together with or instead of the screen display.

[0054] As described above, according to the navigation system 1 of the first embodiment, the route search unit 111 of the server 10 searches for a route from the road network data stored in the route information DB 142, excluding terminal links (i.e., links that are dead ends), which are links in which only one of the nodes located at both ends of the link is connected to another link (step S102: rule a1). This makes it possible to provide a route search device (server 10) that can suppress guidance of routes that include dead ends. Furthermore, according to the navigation system 1 of the first embodiment, the determination of whether a link is a terminal link (a link that is a dead end) is made using the link connection relationship in the route information DB 142 used for route search (rule a1). This makes it possible to suppress guidance of routes that include dead ends, regardless of whether information is available or not, compared to when special information is required separately (FIG. 4).

[0055] Furthermore, according to the navigation system 1 of the first embodiment, the route search unit 111 of the server 10 searches for a route from the road network data stored in the route information DB 142, excluding, in addition to terminal links, specific links in which one of the nodes located at both ends of a link is connected only to a terminal link (i.e., links leading to a dead end) from the search targets (step S102: rule a2). Therefore, it is possible to provide a route search device (server 10) that can suppress guidance of routes that include dead ends. Furthermore, according to the navigation system 1 of the first embodiment, the determination of whether a link is a specific link (a link leading to a dead end) is made using the link connection relationship in the route information DB 142 used for route search (rule a2). Therefore, compared to when special information is separately required, it is possible to suppress guidance of routes that include dead ends without being affected by the availability of information (FIG. 5).

[0056] In cases where the road length is long even if the link is a dead end, there is a demand for guidance on a route that includes the dead end. In this regard, according to the navigation system 1 of the first embodiment, when a node that is not connected to any other link among the nodes located at both ends of a terminal link is set as an end node, if the link length from the end node to the intermediate point is equal to or greater than a predetermined threshold, the route search unit 111 of the server 10 does not exclude the terminal link (a link that corresponds to a dead end) from the search target (step S102: rule a3). Therefore, in cases where the road length is long even if the link is a dead end, the route search unit 111 can provide guidance on a route that includes the dead end (FIG. 6(A)).

[0057] Even if a link is a dead end, if it faces either the departure point or the destination, there is a demand for guidance on a route that includes the dead end. In this regard, according to the navigation system 1 of the first embodiment, if an end link is a link that faces either the departure point or the destination, the route search unit 111 of the server 10 does not exclude the end link (a link that corresponds to a dead end) from the search target (step S102: rule a4). Therefore, even if a link is a dead end, if it faces either the departure point or the destination, the route search unit 111 can provide guidance on a route that includes the dead end (FIG. 7(A)).

[0058] Compared to normal main streets, residential areas with many private homes have many narrow roads where vehicles make U-turns, and there is a lot of traffic of people, bicycles, and the like. In this regard, according to the navigation system 1 of the first embodiment, when a searched route includes a route that makes a U-turn at a certain link, the route search unit 111 of the server 10 excludes the links that make up the U-turn route from the search targets, searches for the route again, and outputs the re-searched route (steps S104, S106, FIG. 8). As a result, the route search device (server 10) further suppresses guidance of routes that include U-turn routes, thereby improving ease of travel on the guided route and improving safety.

[0059] In recent years, the spread of internet shopping has led to an increase in the demand for logistics services, and an increase in the number of people (delivery personnel) engaged in the task of delivering packages such as merchandise to designated destinations. In this regard, according to the navigation system 1 of the first embodiment, the route search unit 111 of the server 10 acquires information on one or more delivery destinations where a user of the route search device (server 10) will stop for the delivery of a package (step S100), and searches for a route from the departure point to the destination via one or more delivery destinations as stopover points (step S102). This makes it possible to provide a route search device specialized for delivery services.

[0060] Furthermore, there are fewer parking lots near residential areas where many private homes are located than near normal main streets. In this regard, according to the navigation system 1 of the first embodiment, the route search unit 111 of the server 10 acquires location information of parking spaces (parking spaces where a vehicle can be safely parked) along the searched route (step S108), and outputs the location information of the parking spaces along with the searched route (FIG. 9). Therefore, in residential areas where there are few parking lots, it is possible to prevent users from parking their vehicles on unsafe roadsides, thereby improving convenience and safety for users.

[0061] B. Second embodiment: 10 is a diagram showing a schematic configuration of a navigation system 1A of the second embodiment. The navigation system 1A of the second embodiment includes a server 10A instead of the server 10 in the configuration described in the first embodiment. In the second embodiment, the processing content of the route search processing executed by the server 10A differs from that of the first embodiment.

[0062] Fig. 11 is a flowchart showing an example of the processing procedure of the route search processing of the second embodiment. The CPU 110A of the server 10A has a route search unit 111A instead of the route search unit 111. The route search unit 111A executes the route search processing shown in Fig. 11. The route search processing of Fig. 11 is the same as the route search processing of Fig. 3 except that steps S104 and S106 (Fig. 3: re-search when an excluded route is included) are not executed.

[0063] As described above, the configuration of the navigation system 1A can be modified in various ways, and the re-search when an excluded route is included may be omitted. The navigation system 1A of this second embodiment can also achieve the same effects as the first embodiment described above. Furthermore, the navigation system 1A of the second embodiment can reduce the processing load on the server 10A and shorten the time from when a processing request is made by the client 30 to when the server 10 responds (step S108 in FIG. 11: sending the delivery route).

[0064] C. Third embodiment: 12 is a diagram showing a schematic configuration of a navigation system 1B of the third embodiment. The navigation system 1B of the third embodiment has a server 10B instead of the server 10 in the configuration described in the first embodiment, and does not have a client 30. The server 10B of the third embodiment executes processing without cooperating with the client 30.

[0065] In addition to the map information DB 141, route information DB 142, and guidance information DB 143, the storage unit 140B of the server 10B also stores delivery plan information 144 in advance. The content of the delivery plan information 144 is the same as the delivery plan information 341 described in FIG. 2. Furthermore, the storage unit 140B stores delivery route information 145 as a result of the route search process (FIG. 3). The CPU 110B of the server 10B has a route search unit 111B instead of the route search unit 111. The route search unit 111B acquires the delivery plan information 144 from the storage unit 140B in step S100 of the route search process (FIG. 3). Furthermore, the route search unit 111B stores the generated delivery route information in the delivery route information 145 in step S108 of the route search process (FIG. 3).

[0066] As described above, the configuration of the navigation system 1B can be modified in various ways, and the server 10B may output the generated delivery route information to the storage unit 140B of the server 10B. The server 10B may also acquire delivery plan information 144 from other devices or servers connected via a network. Similarly, the server 10B may output the delivery route information generated in the route search process (FIG. 3) to other devices or servers connected via a network. The navigation system 1B of this third embodiment can also achieve the same effects as the first embodiment described above.

[0067] D. Fourth embodiment: Fig. 13 is a diagram showing a schematic configuration of a navigation system 1C of the fourth embodiment. The navigation system 1C of the fourth embodiment has a client 30C instead of the client 30 in the configuration described in the first embodiment, and does not have the server 10. The client 30C of the fourth embodiment executes processing without cooperating with the server 10. In this embodiment, the client 30C corresponds to a "route search device."

[0068] In addition to delivery plan information 341 and delivery route information 342, a map information DB 343, a route information DB 344, and a guidance information DB 345 are pre-stored in the memory unit 340C of the client 30C. The map information DB 343 is similar to the map information DB 141 described in FIG. 1. The route information DB 344 is similar to the route information DB 142 described in FIG. 1. The guidance information DB 345 is similar to the guidance information DB 143 described in FIG. 1. The CPU 310C of the client 30C has a route search unit 312 in addition to the guidance unit 311. The route search unit 312 is a functional unit that performs the same processing as the route search unit 111 described in FIG. 1 and FIG. 3.

[0069] As described above, the configuration of the navigation system 1C can be modified in various ways, and the client 30C may be configured as a route search device. The map information DB 343, route information DB 344, and guidance information DB 345 may be stored in an external data server, and the route search unit 312 may connect to the data server each time during the processing of FIG. 3 to obtain the necessary data. Furthermore, in order to have the client 30C, which has lower processing power than the server 10 (FIG. 1), execute the route search process (particularly, step S102 of FIG. 3), restrictions may be imposed on the search speed and search distance range in the route search process. The navigation system 1C of this fourth embodiment can also achieve the same effects as those of the first embodiment described above.

[0070] E. Variations: In the above embodiment, a part of the configuration realized by hardware may be replaced by software, and conversely, a part of the configuration realized by software may be replaced by hardware. In addition, the following modifications are also possible.

[0071] Variation 1: In the above embodiment, an example of the configuration of the navigation system, server, and client is shown. However, the configuration of each device can be arbitrarily adopted. For example, at least a part of each DB possessed by the server and client may be stored in a device other than the server and client (including an external server connected via the Internet).

[0072] In the above embodiment, the navigation system is a system for providing delivery route guidance, in other words, a system used in delivery work. However, the navigation system is not limited to delivery work, and can be configured as a system for general users that provides normal route guidance.

[0073] Variation 2: In the above embodiment, the route search process (FIGS. 3 and 11) has been described using an example of a processing procedure. However, these processing procedures can be modified in various ways, and the processing content of each step may be added, omitted, or changed, and the execution order of each step may be changed.

[0074] For example, in step S102, rules a1 to a5 are exemplified for excluding terminal links and specific links from search targets. However, any combination of one or more of these rules a1 to a5 may be employed. For example, rule a1 alone may be executed, or rule a1 and rule a3 may be executed in combination.

[0075] For example, in step S108, the delivery route information includes the route searched in step S102 or step S104 and parking space information. However, the parking space information may be omitted. Furthermore, the delivery route information may include other information.

[0076] Variation 3: The present invention is not limited to the above-described embodiments, examples, and modifications, and can be realized in various configurations without departing from the spirit of the present invention. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate. [Explanation of symbols]

[0077] 1, 1A~1C...Navigation system 10, 10A, 10B...Server 30,30C…Client 110, 110A, 110B...CPU 111, 111A, 111B...Route search section 120…Communications Department 130...ROM / RAM 140,140B…Storage section 141...Map information DB 142...Route information DB 143...Guidance information DB 144...Delivery plan information 145...Delivery route information 310,310C...CPU 311…Information Department 312...Route search section 320…Communications Department 330...ROM / RAM 340,340C…Storage section 341...Delivery plan information 342...Delivery route information 343...Map information DB 344...Route information DB 345...Guidance information DB 350…Input / output section 360…Current position acquisition unit

Claims

1. A route search device, a route information storage unit that stores road network data including information on nodes and information on links connecting the nodes; a route search unit that searches for a route from a departure point to a destination; Equipped with The route search unit searching for the route from the road network data, excluding terminal links, which are links in which only one of the nodes located at both ends of a link is connected to another link, from the search targets; A route search device that outputs the searched route.

2. 2. The route search device according to claim 1, The route search unit searches for the route from the road network data after excluding from the search target, in addition to the terminal links, specific links in which one of the nodes located at both ends of a link is connected only to the terminal link.

3. 3. The route search device according to claim 1 or 2, The route search unit Searching for a route from the departure point to the destination via a predetermined waypoint; A route search device that searches for the route without excluding the terminal link from the route search target when the node located at both ends of the terminal link that is not connected to any other link is set as the terminal node and the link length from the terminal node to the intermediate point is equal to or greater than a predetermined threshold.

4. 4. The route search device according to claim 1, When the terminal link is a link facing either the departure point or the destination, the route search unit searches for the route without excluding the terminal link from the search target.

5. 5. A route search device according to claim 1, The route search unit If the searched route includes a route that makes a U-turn on a certain link, the link that constitutes the U-turn route is excluded from the search, and the route is searched again; A route search device that outputs the re-searched route.

6. 6. A route search device according to claim 1, The route search unit Acquire information on one or more delivery destinations where a user of the route search device will stop for delivery of a package; A route search device that searches for the route from the departure point to the destination via the one or more delivery destinations as intermediate points.

7. 7. The route search device according to claim 6, The route search unit acquiring location information of parking spaces located near roads where the vehicle can be safely parked, the location information of the parking spaces being located along the searched route; A route search device that outputs the acquired position information of the parking space in addition to the searched route.

8. A route search method, comprising: Executing a step of searching for a route from a departure point to a destination using road network data including information on nodes and information on links connecting the nodes; In the searching step, searching for the route from the road network data, excluding terminal links, which are links in which only one of the nodes located at both ends of a link is connected to another link, from the search targets; and outputting the route found.

9. A computer program for an information processing device, A computer program that executes a step of searching for a route from a departure point to a destination using road network data including information on nodes and information on links connecting the nodes, the computer program comprising: In the searching step, searching for the route from the road network data, excluding terminal links, which are links in which only one of the nodes located at both ends of a link is connected to another link, from the search targets; A computer program that outputs the searched route.

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