JP5792491B2 - Guidance system - Google Patents

Description

The present invention relates to a guidance system that presents information that supports road traffic.

2. Description of the Related Art Navigation systems that search and guide a route from a specified departure point to a destination using network data that expresses roads as links and nodes have become widespread. Some also provide information that assists the passage of the user at the time of guidance. Patent Document 1 discloses a technology for voice guidance of a warning message while traveling in a caution area such as a residential area. Patent Document 2 discloses a technique for totalizing the characteristics of a point where an accident or the like is likely to occur, that is, a point where a so-called near-miss occurs, and presenting information indicating the degree of risk based on the total result.

In route search, since the network is not maintained for all roads, a point outside the network may be designated as the destination. In this respect, it can be said that the guidance of the prior art is insufficient. Patent Document 3 discloses a technique for performing a route search using two types of network data when a point away from a link or node is designated as a destination. First, the nearest node is obtained from the destination, and a route search with this node as the end point is performed. From the end point to the destination, a route search is performed using complementary data obtained separately. Patent Document 4 refers to an area deviated from network data as a specific area, obtains a connection road from the main road where the network data is maintained to the specific area, and searches for a route using the intersection of the main road and the connection road as a guide point. The technology to do is disclosed.

JP 2002-213970 A JP 2009-104531 A JP 2006-84256 A Japanese Patent No. 3385975

In the prior art, provision of information for supporting traffic may be insufficient. FIG. 1 is an explanatory diagram showing an example of route guidance in the prior art. In an area surrounded by roads RW1 to RW4 in the figure, network data including links LW1 to LW4 and nodes N12, N23, N34, and N41 is prepared for the roads RW1 to RW4. Is not maintained. In addition, buildings HA to HJ exist in this region.

Consider a case where a route is guided along the link LW1 in such a state. The range where the buildings HA to HD exist is a residential area, but the link LW1 runs away from this residential area. Therefore, even if the residential area is set as a caution area, the warning message is not guided while the link LW1 is being passed. However, as long as the road RN from the residential area intersects, there is a danger of popping out at the intersection of the point CP, and the guidance of the prior art is insufficient in this respect. In order to be able to guide the warning message on the link LW1, it is necessary to set a caution area including the link LW1, but this requires manual operation while the operator confirms the road conditions on the map. There is no choice but to set a caution area, and the work burden becomes very large. Further, since the link LW1 does not intersect with other links at the point CP, the point CP cannot be recognized as an intersection as long as the network data is viewed. In such a state, for example, when traveling upward from the node N41 on the link LW1, if the user guides a right turn at the node N12 as “the next intersection is a right turn”, the user points to the point CP If the vehicle is in front of the vehicle, there may be a misunderstanding of whether to enter the road RN. The problem of presenting appropriate information for supporting traffic to the user is not limited to the above-described warning message or the presence of an intersection. In addition, the usefulness of presenting information such as the degree of danger to the user at a point near the current position while traveling is not limited to the case where the route is searched and the route is guided.

In view of these problems, an object of the present invention is to appropriately present various kinds of information that supports road traffic, such as a degree of danger, to a user regardless of whether or not a route search is performed.

The present invention can be configured as a guidance system that presents information that supports road traffic. The present invention is not limited to performing route search and route guidance. The guidance system includes a map database storage unit, a position detection unit, and a guidance unit. The map database storage unit stores network data representing roads as nodes and links, and feature data for storing polygons for drawing features including roads. Network data can be prepared by mixing a main network that can be used for route search of automobiles in consideration of traffic regulations and a quasi network that can be used for route searches but cannot be completely developed for traffic regulations. Good. The feature data stores arrival point data for the feature. The arrival point is a point on the road where the network data is maintained as a road through which automobiles can pass, and can be reached from any feature corresponding to the destination through any road. The position detection unit detects the current position. A GPS (Global Positioning System) or the like can be used. Then, the guidance unit presents information according to the type of the feature corresponding to the arrival point for the arrival point having a predetermined positional relationship with the current position. The predetermined positional relationship may be within a predetermined distance range from the current position, or may be within a predetermined distance range in front of the current position after detecting a traveling direction from a change in the current position. Further, as will be described later, when a route search is performed, a range that is ahead of the current position on the searched route may be used.

The arrival point is the point from the feature to the road where the main network is maintained, so if you look at the type of feature corresponding to the arrival point, you can guess the actual usage of the arrival point . For example, if there is a parking lot at a feature corresponding to the arrival point, it is estimated that the arrival point has a car in and out. If it is an arrival point corresponding to a house, it is assumed that there is a possibility of people jumping out, including traffic, including infants. Therefore, even if the location is not an intersection on the network, the user can be presented with a warning regarding the location of the intersection where the arrival point exists or traffic, according to the type of the arrival point. Moreover, if it is an arrival point corresponding to a restaurant, a store, a tourist attraction, etc., the location, town information, tourist information, etc. can be provided depending on the purpose of the user. As described above, according to the guidance system of the present invention, since various features can be associated with the network via the arrival point, it is possible to provide guidance based on the local situation that cannot be grasped only by the network data. .

The guidance system may perform route search and route guidance. An input unit provided for route search inputs a starting point and a destination. As the departure place, the current position of the user may be automatically input. As the destination, a specific building or the like included in the feature data may be specified, or a coordinate value may be specified on the map. A route search unit provided for route search performs a route search from the departure point to the destination with reference to the network data. A well-known method such as the Dijkstra method can be applied to the route search. In this aspect, the guidance unit performs route guidance by presenting a route to the user in addition to presenting information. The route can be presented by a method such as display on a display or voice guidance. In this case, it is preferable to present the above information to the arrival point on the searched route. When the route search is performed, the usefulness of the information on the arrival point on the route is high. Therefore, by taking such an aspect, it is possible to present highly useful information to the user.

In the present invention, the arrival point can also be used when searching for a route. That is, the route search unit may acquire an arrival point corresponding to the destination and perform a route search from the departure point to the arrival point. In this way, even when a destination is set at a point off the network, an appropriate route can be presented. Since the arrival point is associated with the feature, it is only necessary to read the data of the arrival point corresponding to the feature designated as the destination. When the destination is designated by the coordinate value, the arrival point acquisition unit may identify the feature corresponding to the designated coordinate and read the data of the arrival point corresponding to the feature. When a feature for which no arrival point has been set is designated as the destination, the arrival point acquisition unit may find the arrival point through a route search starting from the destination. For route search in this case, it is possible to use a quasi-network where traffic regulations are not completely developed, and roads where no network is established. For roads that do not have a network, it is possible to search for a route by treating the degree of connection of polygon data of roads included in the feature data as network data.

The feature data of the present invention may store an entry / exit point that designates a point on the road facing the entrance to the feature. In this case, the route guidance unit can exclude the feature whose arrival point and entrance / exit point coincide with each other from the information presentation target. If the entrance and exit points coincide with each other, it means that the feature entrance faces the road of the main network. Such a feature can be visually recognized by a user who is traveling along the route, so there is no need to guide it again. If guidance is provided for such a feature, too much information is provided to the user, which may cause confusion. According to the above-described aspect, since the feature facing the route can be excluded from the information presentation target, it is possible to avoid an excessive amount of information presented to the user. The determination of whether or not the feature faces the route is not limited to the above-described mode, and various methods can be used. For example, the coordinates of the feature may be acquired, and the information presentation target may be a distance that is equal to or greater than a predetermined value to the route being traveled. Further, in order to avoid an excessive amount of information to be presented, information presentation targets may be narrowed down to arrival points associated with a predetermined number or more of features.

The specific aspect of the route guidance in this invention is illustrated. For example, for a point where an arrival point corresponding to a parking lot or a feature parking space exists, the point where the arrival point exists can be guided as an intersection. Similar guidance may be applied even when data is not configured as an intersection on the network data. This kind of arrival point means a point where a car enters and leaves the parking lot. Even if the point is not an intersection on the network, a road with enough width to allow the car to cross It shows that it is a point. Therefore, by guiding such a point as an intersection, it is possible to determine the route without misunderstanding for the user. The guidance mode can take various methods. As an example, the presence of an intersection may be simply indicated as “There is an intersection”. In addition, in FIG. 1, when the link LW1 is traveling upward and before reaching the intersection of the point CP, on the premise that this intersection exists, “turn right at this second intersection” You may make it guide the right turn of node N12. Furthermore, since the above-mentioned intersection is a place where a car may pass, a traffic alert may be issued such as "There may be a car coming and going at this intersection".

In the above aspect, the content of information presentation may be set according to how the parking lots corresponding to the arrival points are arranged on the left and right sides of the route. In this way, guidance according to local conditions can be provided. For example, if there is a parking lot only on one of the left or right, guide it as a "three-way" instead of an "intersection", and if there is a parking lot on both sides, say "an intersection" or "four-way" By guiding, it is possible to provide guidance that is easy for the user to understand. Also, if there is a parking lot only on one side, or if the parking lot is located only on the right side of the direction of travel, it is judged that the risk of the car coming out is relatively low and The alerting may be omitted, and when there are parking lots on both sides, or when the parking lot is located only on the left side with respect to the traveling direction, the alerting may be performed. In general, if alerting is frequently performed, the user tends to be paralyzed by alerting, but this paralysis can be achieved by alerting after evaluating the degree of risk according to the arrangement of the parking lot. It is possible to suppress the tendency and to perform effective alerting.

As another mode of guidance, information that alerts the user to safe passage may be presented to a point where an arrival point corresponding to a house that is one of the features exists. Such an arrival point means that there is traffic of people including infants from the house, and there is a risk of jumping out. Safe traffic can be supported by calling attention to these points. The alerting can take various methods. It may be just a presence such as “It is a residential area”, or it may be a content that calls attention such as “There is a risk of popping out”. The contents may be changed according to the number of houses corresponding to the arrival point and the arrangement. For example, the more the number of houses, the more the content can be emphasized. In addition, when there is a house only on either the left or right side of the route, guidance can be given as “There is a possibility of jumping out from the left (from the right)”. Information may be presented only when the number of houses exceeds a predetermined number. By doing so, frequent alerting can be avoided, and the tendency of paralysis to alerting can be alleviated.

In the above-described aspect, the density at which arrival points corresponding to houses appear along the route may be obtained, and the content of information presentation for alerting may be set according to the density. For example, if the density of arrival points is high, such as when driving in a residential area, refrain from presenting warning information, or be careful about the entire area, such as “I will pass through an area where there is a risk of jumping out for a while” It can take the form of arousal. When the density of arrival points is low, attention may be actively given. In addition, when alerting when the number of houses associated with the arrival point is a predetermined number, the condition of information presentation is made stricter by increasing the predetermined number as the judgment criterion as the density of arrival points increases. Also good. By these aspects, it can suppress that information presentation of alerting becomes excessive.

The guidance according to the present invention is not limited to a mode in which traffic alerts and guidance are given as in the case where the arrival point corresponds to a parking lot or a house. When the arrival point corresponds to a restaurant or a store, guidance such as “There is a restaurant street on the right side” or “There is a store street” may be given according to the density. When searching for a route, if you set a purpose such as having a meal on your way to the destination, you will extract the arrival point corresponding to the restaurant, and in the process of route guidance, there is an Italian restaurant on the right side. Information according to the purpose may be presented as follows. By presenting information according to the type of feature associated with the arrival point in this way, even if the feature is not selected as the destination by the user, Information that matches the intention can be presented.

In addition, the present invention may be configured as a route guidance method using a computer, or may be configured as a computer program for causing a computer to execute such route guidance. Moreover, you may comprise as a computer-readable recording medium which recorded such a computer program. Recording media include flexible disks, CD-ROMs, magneto-optical disks, IC cards, ROM cartridges, punch cards, printed matter printed with codes such as bar codes, computer internal storage devices (memory such as RAM and ROM), and Various media that can be read by a computer, such as an external storage device, can be used.

It is explanatory drawing which shows the guidance method in a prior art. It is explanatory drawing which shows the structure of a guidance system. It is explanatory drawing which shows the structure of a map database. It is explanatory drawing shown about the setting of an arrival point. It is a flowchart of a feature data maintenance process. It is a flowchart of a route guidance process. It is a flowchart of an arrival point acquisition process. It is a flowchart of a guidance object intersection setting process. It is explanatory drawing which shows the guidance object intersection setting example (1). It is explanatory drawing which shows the guidance object intersection setting example (2). It is explanatory drawing which shows the example which linked | related guidance object intersection data with network data.

Embodiments of the present invention will be described in the following order. A. System configuration: B. Data structure: B1. Network data: B2. Character data: B3. Feature data: B4. Setting of arrival point: C.I. Development of feature data: D. Route guidance processing: D1. Overall processing: D2. Arrival point acquisition processing: D3. Guidance target intersection setting process: D4. Guidance example: E. Variations:

A. System Configuration: FIG. 2 is an explanatory diagram showing the configuration of the guidance system. The guidance system is configured as a navigation device 100. In this embodiment, the navigation device 100 is connected to the server 200 that provides map data and the like through the network NE1, and can receive the update of the map database from the server 200. The navigation device 100 may be configured to operate stand-alone, or may be configured to execute part of its functions on the server 200 or the like. The server 200 is connected to a personal computer 300 as a database generation device via a network NE2. The database generation device 300 is a device for generating and updating a database stored in the server 200 in accordance with an operator instruction.

The server 200 includes a map database storage unit 210, a transmission / reception unit 201, and a database management unit 202. Although the transmission / reception unit 201 and the database management unit 202 may be configured in hardware, in this embodiment, the transmission / reception unit 201 and the database management unit 202 are configured by software by installing a computer program that realizes these functions.

The transmission / reception unit 201 communicates with the navigation device 100 and the database generation device 300 via the networks NE1 and NE2. In this embodiment, data in the map database storage unit 210, commands related to its provision and storage, and the like are communicated. The database management unit 202 reads the map information requested from the navigation device 100 and the database generation device 300 from the map database storage unit 210, and stores the map data generated by the database generation device 300 in the map database storage unit 210. . The map database storage unit 210 stores feature data 211, character data 212, and network data 213. The feature data 211 is polygon data of features to be drawn on a map such as roads and buildings. The character data 212 is character information to be displayed on the map. For example, text information such as a building name and a place name is included. The network data 213 is data representing roads as nodes and links. The network data 213 of this embodiment includes main network data and quasi-network. Main network data is data for which traffic regulations have been sufficiently established by field surveys, and can be used without problems for vehicle route search. The quasi-network data is data that cannot be said to have sufficient traffic regulations, and is preferably data that is not used in the vehicle route search.

The navigation device 100 includes various functional blocks that operate under the main control unit 101. In the present embodiment, the main control unit 101 and each functional block are configured by installing software that realizes the respective functions, but a part or all of them may be configured by hardware. The transmission / reception unit 102 communicates with the server 200 via the network NE1. In this embodiment, transmission / reception of a map database and a command for receiving the map database are mainly performed. The command input unit 103 inputs an instruction from the user through operations of buttons, levers, touch panels, and the like provided in the navigation device 100. Examples of instructions in the present embodiment include designation of a starting point and a destination for route search. The GPS input unit 104 inputs a user's current position using GPS (Global Positioning System). The map database storage unit 105 stores the map database provided from the server 200. In the present embodiment, the entire map database included in the server 200 is also stored in the map database storage unit 105 in the navigation device 100. However, only the part necessary for route search and map display is stored in the server each time. It is good also as what is acquired from 200. The route search unit 107 performs a route search with reference to the map database storage unit 105. The display control unit 106 uses the map database storage unit 105 to display guidance such as a map and a searched route on the display of the navigation device 100.

The database generation device 300 includes various functional blocks that operate under the main control unit 301. In the present embodiment, the main control unit 301 and each functional block are configured by installing software that realizes the respective functions, but a part or all of them may be configured by hardware. The transmission / reception unit 302 communicates with the server 200 via the network NE2. In this embodiment, transmission / reception of a map database and commands for managing the map database are mainly performed. The command input unit 303 inputs an instruction from the operator through operations such as a keyboard and a mouse. The display control unit 304 displays a map or the like on the display of the database generation device 300. The map database storage unit 305 stores the map database stored in the map database storage unit 210 of the server 200. In the present embodiment, the entire map database of the server 200 is stored, but only a portion necessary for processing may be stored. The arrival point calculation unit 307 obtains an arrival point for the feature stored in the map database storage unit 305. The arrival point refers to a point where the main network data, that is, the network data that can be used for route search is reached by following the road from the feature. The database maintenance unit 306 stores the arrival point obtained by the arrival point calculation unit 307 in the map database storage unit 305 and updates the map database stored in the map database storage unit 210 of the server 200.

B. Data Structure: FIG. 3 is an explanatory diagram showing the structure of the map database. An overview of information stored in feature data, character data, and network data is shown.

B1. Network data: Network data is data representing roads as links and nodes. In this embodiment, two types of network data, main network data and semi-network data, are prepared. In the figure, links L1 to L4 and nodes N1 and N2 indicated by solid lines are main network data, and links L11 to L13 and nodes N11 and N12 indicated by broken lines are semi-network data. Both main network data and semi-network data store link data and node data belonging to each. The link data records the link ID, which is identification information, the coordinates of the point sequence forming each link, the type of national road / prefectural road, the number of lanes, other attribute information, and traffic regulation information. The node data records identification information such as node ID, coordinates, and traffic restrictions.

B2. Character data: The character data 212 is data that defines characters for displaying the name of a feature, the name of the place, and the like. In the figure, an example of data for displaying the name of the building BLD is shown. Character data stores information such as contents, position, feature, font, size, and the like. The content is a character string to be displayed, and in the example in the figure, is the company name “ΔΔ (stock)”. The position is a position where a character is displayed. In this embodiment, the coordinate value is designated with the lower left point P5 of the character string as a reference point. The feature is a polygon name of the feature data with which the character is associated. The font and size are designation of the font and size for display. In addition, various attributes such as color and bold may be specified.

B3. Feature data: The structure of the feature data 211 is shown by taking the building H1 as an example. The feature data 211 is polygon data for drawing features such as buildings and roads, and stores names, shapes, representative points, doorway lines, arrival points, attributes, and the like. The name is the name of the feature. An ID unique to the polygon may be used. The shape is a sequence of coordinates indicating the vertexes of the polygon of the feature. In the illustrated example, the coordinates of the vertices P1, P2, P3, and P4 of the polygon of the building H1 are stored. The representative point is the coordinates of the point C that represents the position of the feature. The representative point often uses the centroid of the feature, but can be set arbitrarily. The entrance / exit line is information for associating a feature with a road. In the case of the building H1, a line segment D for exiting from the entrance to the road is registered as an entrance / exit line. Specifically, the coordinates of both ends of the line segment D are registered. As for the entrance / exit line, only the end point on the road among the line segment D may be registered. In addition, the entrance / exit line is set for a feature such as a building or a parking lot, and it is not necessary to set it for all the features. In the example in the figure, the entrance / exit line DB1 on the front side for the building BLD, the entrance / exit line DB2 on the parking lot BLDP side, the entrance / exit lines DH2 to DH4 for the buildings H2 to H4, and the entrance / exit line DPK for the parking lot PK are set. Has been. You may set the information which shows uses, such as an entrance / exit used for a person's entrance / exit, a parking lot, with respect to the entrance / exit line.

The arrival point G is the coordinates of a point on the network that can be reached via any road from the end point on the road of the feature entry / exit line. In the case of the building H1, the arrival point G is set on the link L2 because it can reach the link L2 via the road R21 associated with the entrance / exit line D as indicated by the dotted line in the drawing. It is also possible to follow the road R21 from the entrance / exit line D in the right direction in the figure, turn right at the node N11 and take a route to the node N2, and use the node N2 as an arrival point. In the present embodiment, since the route from the building H1 to the node N2 is shorter than the route from the building H1 to the node N2, the setting is made in this way. Since the arrival point need not be limited to one, the node N2 may also be set as the arrival point. In the example of the figure, the arrival point for the buildings H2 to H4 is set as a point GH. For the building BLD, the points GH and GBLD2 are set. The arrival point can be set in the parking lot as well as the entrance / exit line, and in the example shown in the figure, the arrival point GPK is set for the parking lot PK. Since the parking lot PK faces the link L2, the end point of the entrance / exit line DPK and the arrival point GPK coincide with each other.

B4. Setting of Arrival Point: FIG. 4 is an explanatory diagram showing setting of the arrival point. The arrival point for the entrance / exit line DB of the building BLD1 is shown. As main network data around the building BLD1, there are a link L7, a node N7, links L5 and L6, and nodes N5 and N6. As the quasi-network data, there is a link L14 indicated by a broken line. The route reaching the main network from the entrance / exit line DB of the building BLD1 via one of the roads includes three types shown by dotted lines in the figure. The route reaches the link L7 via the road R24, and the route reaches the link L6 and the link L5 via the road R25. The points where these routes reach links L7, L6, and L5 are arrival points G7, G6, and G5.

These arrival points can be obtained by route search. In this embodiment, each feature is related to one of the roads by an entrance / exit line, and therefore arrives by a route search starting from an entrance / exit point, that is, an end point on the road facing the entrance to the feature. Find a point. This route search may use all of the main network data, quasi-network data, and road polygons. Road polygons are not composed of links and nodes, but because there is data specifying adjacent polygons, the relationship between polygons is defined, and as with links and nodes, routes It can be used for searching. As a result of the route search starting from the entrance / exit point, a point where the main network data is reached may be set as the arrival point.

When three arrival points G7, G6, and G5 are found as in the example of the figure, these three points may be used as the arrival point of the building BLD1, for example, the point where the road from the feature is the shortest , Even if you select by the criteria such as the point with the shortest distance from the feature, the point where there is a lot of overlap between the route from the feature to the arrival point and the quasi-network data, or the point close to the direction from the feature to the departure point Good. In the example shown in the figure, if the route or distance from the feature is selected as a reference, the point G5 closest to the building BLD1 is the arrival point. If an overlapping portion with the quasi-network data is selected as a reference, the point G6 becomes the arrival point. If the departure point is in the leftmost direction in the figure, the point G7 becomes the arrival point if the direction of the departure point is selected as a reference.

In this embodiment, the arrival point is set according to the above-described procedure, and is set in advance in the feature data 211. The arrival point may not be set in advance, but may be obtained in the course of processing such as route search.

C. Maintenance of Feature Data: FIG. 5 is a flowchart of the feature data maintenance process. This is a process mainly executed by the database maintenance unit 306 and the arrival point calculation unit 307 of the database generation device 300, and is a process executed by the CPU of the database generation device 300 in terms of hardware.

The CPU reads the map data in the range specified by the operator from the map database storage unit 305, and displays the map on the display (step S10). The CPU inputs an instruction such as a name, a polygon shape of the feature, a representative point, and an attribute to the feature to be processed (step S11). When processing an existing feature, since these pieces of information are already stored in the feature data, only the update-needed portions need be corrected. Further, the CPU inputs designation of the entrance / exit line and usage (step S12). The entrance / exit line is information for associating a feature with a road. A plurality of entrance / exit lines may be set for the feature. The application can be set for each entrance / exit line. For example, it is specified in the form of an entrance / exit used for entering / exiting people or a parking lot. The entrances used for entering and exiting people may be subdivided into entrances and back doors.

The CPU performs an arrival point search process to obtain an arrival point corresponding to each entrance / exit line of the feature (step S13). This process is a route search starting from the entrance / exit point described in FIG. This route search may use all of the main network data, quasi-network data, and road polygons. Road polygons are not composed of links and nodes, but because there is data specifying adjacent polygons, the relationship between polygons is defined, and as with links and nodes, routes It can be used for searching. As a result of the route search starting from the entrance / exit point, a point where the main network data is reached may be set as the arrival point. A plurality of arrival points may be searched for each entrance / exit point. In such a case, it may be possible to narrow down to any arrival point and register it in the feature data. However, in this embodiment, all searched arrival points are registered. By doing so, there are more choices of arrival points in the route search described later, and the possibility that a more suitable route can be presented increases.

Based on the above processing, the CPU stores the name, feature polygon shape, representative point, attribute, entry / exit line, usage, and arrival point data in the feature data, and updates the feature data (step S14). If there are other features to be processed, this process is repeatedly executed according to the operator's instructions.

D. Route guidance processing: D1. Overall Processing: FIG. 6 is a flowchart of route guidance processing. This is a process mainly executed by the route search unit 107 and the display control unit 106 of the navigation apparatus 100, and is a process executed by the CPU of the navigation apparatus 100 in terms of hardware.

The navigation apparatus 100 inputs a starting point and a destination (step S20). The departure point may be specified by the user, or the current position acquired by GPS or the like may be set as the departure point. As the destination, a feature may be specified, or may be specified by coordinates.

Next, the navigation apparatus 100 acquires the arrival point with respect to the designated destination (step S30). In this embodiment, the arrival point is stored in the feature data 211. Therefore, when the feature as the destination is designated, the navigation device 100 may read the arrival point from the feature data corresponding to the designated feature. When the destination is designated by coordinates, the navigation apparatus 100 identifies which polygon the coordinates are included in, and reads the arrival point corresponding to the feature data of the identified polygon. . There may be multiple arrival points for a feature. The contents of the arrival point acquisition process will be described later.

Next, the navigation device 100 performs a route search starting from the obtained arrival point (step S50). When a plurality of arrival points are obtained, the navigation device 100 selects an arrival point and a route to be route guidance targets. The navigation device 100 may take a method of displaying the arrival point and the route on a map and allowing the user to select directly. Further, the navigation device 100 may automatically select according to some selection condition. Various selection conditions can be applied to the selection, but in the present embodiment, conditions selected in advance by the user from the following three conditions are used. (1) Select an arrival point that minimizes the cost (hereinafter referred to as “route cost”) by route search from the departure point to each arrival point. (2) Select an arrival point that minimizes the sum of the route cost and the cost from the destination to each arrival point (hereinafter referred to as “arrival point cost”). (3) Select the arrival point with the shortest distance to the line connecting the departure point and the destination. That is, it is a condition in which a perpendicular line is dropped from the arrival point with respect to the line segment connecting the departure point and the destination, and evaluation is performed based on the distance. For arrival points that are in a positional relationship in which no perpendicular line can be drawn with respect to the line segment, the linear distance to the destination is used. This condition is based on the idea that if an arrival point located between the departure point and the destination is selected, a route with a low sum of the route cost and the arrival point cost can be obtained.

Next, the navigation apparatus 100 performs a guidance target intersection setting process (step S60). In this embodiment, the navigation device 100 provides guidance for assisting the user to travel, such as guidance for dangerous places, in addition to route guidance such as turning left and right during route guidance. The guidance target intersection setting process is a process in which the navigation device 100 sets an intersection that is a target for guidance. In the present embodiment, the following two types of intersections are set as guidance targets. The first is guidance for virtual intersections. Since network data is not maintained for all roads, there are actually road intersections even if the network data is not configured as an intersection. In the present embodiment, such a location is referred to as a virtual intersection in the sense of a virtual intersection when viewed from the network data. In the present embodiment, the navigation device 100 selects a guidance target intersection from such virtual intersections, and guides the existence of the intersection to the user. The second is guidance for intersections requiring attention. At intersections crossing roads that face houses, there are people, including infants, and there are also dangers such as jumping out. In the present embodiment, the navigation device 100 alerts the user using such an intersection as a guidance target intersection. The specific contents of the guidance target intersection setting process for performing these guidance will be described later.

When the information necessary for route guidance is obtained in this way, the navigation apparatus 100 performs route guidance according to the following procedure. The navigation device 100 acquires the current position of the user (step S90), and displays the searched route and the current position on the display (step S92). The navigation apparatus 100 may perform voice guidance of the route together with the display of the route. In addition, when the user approaches the guidance target intersection, the navigation device 100 outputs a traffic guidance (step S94). As described above, the existence of a virtual intersection or the like is indicated, or the attention of a critical intersection is alerted. The navigation device 100 repeatedly executes the above processing until the user arrives at the destination (step S96).

The processing procedure in the route guidance process is not limited to this. For example, the guidance target intersection setting process (step S60) may be changed to a process subsequent to the route / current position display process (step S92). That is, when the route search processing for the arrival point in step S50 is completed, the navigation device 100 performs the processing for acquiring the current position in step S90 and displays the route and current position in step S92 that has been performed subsequently. After the process is completed, the guidance target intersection setting process in step S60 is performed. And after the guidance object intersection setting process of step S60 is complete | finished, the process of the traffic guidance output of step S94 is performed. In the case of such a processing procedure, the execution time of the guidance target intersection setting process per time is shortened by performing the guidance target intersection setting process after the process of acquiring the current position. It is possible to guide the intersection.

D2. Arrival Point Acquisition Process: FIG. 7 is a flowchart of the arrival point acquisition process. This process corresponds to step S30 of the route guidance process (FIG. 6), and is a process for obtaining an arrival point corresponding to the designated destination. The navigation device 100 reads feature data corresponding to the destination (step S32). When the destination designates the feature, the navigation apparatus 100 may read the feature data corresponding to the designation. When the destination is designated by coordinates, the navigation device 100 reads the feature data of the feature including the coordinate point. When the arrival point is set in the feature data (step S34), the navigation device 100 reads the set arrival point data (step S36). When the arrival point is not set (step S34), the navigation apparatus 100 reads the entrance / exit line data (step S38), performs the arrival point search process, and obtains the arrival point (step S40). The arrival point search process is the same as the process described in step S13 of the feature data maintenance process (FIG. 5).

And the navigation apparatus 100 selects an arrival point according to route search mode. If a search mode is specified in which the user walks from the arrival point to the destination (step S42), the navigation apparatus 100 prioritizes the cost from the arrival point to the destination, that is, the arrival point having a low arrival point cost. (Step S44). The cost is an evaluation value for evaluating each route in route search, and can be set based on a distance, a time required for movement, and the like. The cost may be set in consideration of a moving load based on the road structure such as up / down slope and stairs. In step S44, in consideration of moving from the arrival point on foot, it means that an arrival point with a low effort required for movement such as a short distance is selected. “Priority” includes a mode in which one arrival point is selected and a mode in which priorities are set for a plurality of arrival points. In the latter case, priorities are set based on the conditions in step S44, and the destinations to be guided are determined in consideration of the selection conditions in step S50 of the route guidance process (FIG. 6). You may make it select.

When the search mode for moving by car from the arrival point to the destination is specified (step S42), the navigation device 100 refers to the use of the entrance / exit line and determines the arrival point corresponding to the entrance / exit line of the parking lot. Prioritize (step S46). The road from the arrival point to the destination is a road that has not been thoroughly investigated for traffic regulations, so there may be roads that are not suitable for car traffic, such as lack of space. However, if it is an arrival point corresponding to the parking lot, the route from the arrival point to the destination is more likely to be suitable for passing the car than other arrival points. According to the aspect of step S46, the navigation apparatus 100 can give priority to the arrival point suitable for moving to the destination by not only guiding the entrance / exit where the car can be parked when arriving at the destination.

D3. Guidance target intersection setting process: FIG. 8 is a flowchart of the guidance intersection setting process. This is a process corresponding to step S60 of the route guidance process (FIG. 6), and is a process for setting a virtual intersection and a point for guidance for alerting.

The navigation device 100 extracts an arrival point on the route (step S62), and selects an unprocessed arrival point as a processing target (step S64). Specifically, the navigation device 100 compares the coordinates of the arrival point obtained by referring to the feature located in the predetermined range around the route and the coordinates of the link obtained by referring to the link data corresponding to the route. Then, the arrival point overlapping the link on the route is extracted. Next, the navigation apparatus 100 extracts all the features corresponding to this arrival point (step S66). Since the arrival point is a point that reaches the main network by following any road from the feature, the arrival point for a plurality of features may be the same point. In step S66, the navigation device 100 searches all the features corresponding to the arrival point to be processed from the feature data.

When the searched feature has a parking lot (step S68), the navigation device 100 identifies an intersection shape based on the position of the parking lot (step S70), and for a location that is an intersection (step S72), virtual An intersection is set (step S74).

The processing content of steps S70 to S74 will be described with a specific example. FIG. 9 is an explanatory view showing a guidance target intersection setting example (1). An example in which parking lots P61 to P65 exist around the link L60 is shown. In each parking lot, representative points C61 to C65, arrival points G61 to G63, and entrance / exit lines D61 to D65 are set. In the case of the parking lot P61, the navigation device 100 does not set a virtual intersection because the arrival point G61 exists on the link L60 but faces the link L60 and is not an intersection. This is because it is not necessary to guide the parking lot visible from the user traveling on the link L60. Various methods can be used to determine whether or not the vehicle is at an intersection. In the present embodiment, the navigation device 100 determines that it is not an intersection when the coordinates of the end point of the entrance / exit line D61 coincide with the coordinates of the arrival point G61, and excludes it from the guidance target. The navigation apparatus 100 can also take the method of determining that it is not an intersection when the distance between the representative point C61 of the parking lot P61 and the link L60 is about the width of the road.

In the case of the arrival point G62, it can be seen that the parking lot P62 exists only on the right side of the link L60 from the coordinates of the representative point of the parking lot P62 corresponding to the arrival point G62. Therefore, the navigation apparatus 100 determines that the “three-way road”. In the case of the arrival point G63, the parking lots P63 and P64 exist on the right side of the link L60, and the parking lot P65 exists on the left side. Therefore, the navigation apparatus 100 determines that the intersection is a “crossover” or a “four-way”. Thus, the navigation apparatus 100 can determine the intersection shape according to the distance between the parking lot and the link and whether the parking lot is arranged on the left or right side of the link.

When the process related to the parking lot is completed, when the number of “houses” corresponding to the arrival point is two or more (step S76), the navigation device 100 sets the arrival point as a critical intersection (step S78). This process will be described with a specific example. FIG. 10 is an explanatory diagram showing a guidance target intersection setting example (2). An example in which the houses H71 to H79 exist around the link L70 is shown. The representative points are points C71 to C79, respectively, and arrival points G71 to G73, G75 and G77, and entrance lines D71 to D79 are set.

The arrival points G71 and G72 are excluded from the intersections requiring attention based on the determination criteria in step S76 because the number of corresponding houses is one. As for the arrival point G71, as in the case of the parking lot, it may be determined that the house H71 faces the link L70 and excluded from the intersections requiring attention. The arrival point G73 has two houses H73 and H74 on the right side of the link L70. The arrival point G74 has a house H75 on the right side of the link L70 and a house H76 on the left side. The arrival point G77 has two houses H77 and H78 on the right side of the link L70 and the house H79 on the left side. Accordingly, the arrival points G73, G75, and G77 are set as cautionary intersections because two or more houses each correspond.

The navigation device 100 performs the above processing for all arrival points on the route, and sets a guidance target intersection. As described above, in this embodiment, a point serving as an intersection among arrival points corresponding to a parking lot and an arrival point corresponding to two or more houses are set as guidance target intersections.

In addition, it is good also as a structure which has beforehand the guidance object intersection data linked | related with network data. Specifically, as shown in FIG. 11, for example, the guidance target intersection data is associated with the link data of the network data, and the guidance target intersection ID, the reference point, the distance from the reference node, and information on the guidance contents are stored. Yes. “Guidance target intersection ID” is information for identifying a guidance target intersection. The “reference point” is information on a point serving as a reference for expressing where the guidance target intersection is located, and a node ID that is information on the end point of the link is stored. “Distance” stores information on the distance from the reference point. The “distance” may be a relative distance with respect to the length of the link. “Guidance contents” stores guidance contents at guidance intersections. Specifically, the guidance content is expressed by “three-way intersection”, “intersection” or “four-way intersection”, and “intersection requiring attention”. A plurality of guidance target intersections can be associated with one link.

D4. Guidance example: A guidance example for a guidance target intersection when a parking lot exists will be described with reference to FIG. As shown in FIG. 9, there are three and four forks at the points G62 and G63, but since the link L60 has no nodes at these points, as long as the link L60 is viewed, the points G62 and G63 The intersection cannot be grasped. However, since the points G62 and G63 are arrival points with respect to the parking lot, it can be seen that these points intersect with a road where cars can enter and leave. In consideration of such a state, the navigation device 100 according to the embodiment sets the virtual intersection of the points G62 and G63 as the guidance target intersection, and performs guidance indicating that the intersection is the intersection.

Specifically, the navigation device 100 guides "There is a three-way in front" when approaching the intersection G62, or guides "There is an intersection (or four-way) in front" when approaching the intersection G63. be able to. Along with these guidance, you may be alerted that "a car may come out". Further, when turning right at the intersection ahead of the point G62 in FIG. 9, the navigation apparatus 100 may guide “turn right at the next intersection after the three-way intersection” based on the three-way intersection at the point G62. Is possible. By doing so, it is possible to prevent the user from making a right turn at the intersection of the point G62.

Further, when the parking lot is located only on the right side with respect to the traveling direction as in the point G62, the navigation device 100 determines that the risk of the car coming out is relatively low, A reminder may be omitted. In addition, when the parking lot is located only on the left side, the navigation device 100 may alert the user to think that the degree of danger is recognized close to the lane where the user travels, and there are parking lots on both the left and right sides. You may make it abbreviate | omit alerting, considering that the degree of danger is low compared with the case where it is located.

In the present embodiment, the navigation device 100 can also provide route guidance to the parking lot P62 using the arrival point G62. That is, the route from the arrival point G62 to the parking lot P62 is guided using the polygon data of the road by searching the route to the arrival point G62 using the network data. In such a case, if guidance is to be made using only network data, point G62 is not recognized as an intersection on the network data, so only guidance to the extent of “near the destination” can be given. I can't. On the other hand, in the present embodiment, the navigation device 100 may perform route guidance “turn right at the next intersection” using the fact that the point G62 can be recognized as an intersection. This makes it possible to present more appropriate information to the user.

An example of guidance for a guidance target intersection when a house exists will be described with reference to FIG. For the arrival point corresponding to the house, the navigation device 100 provides guidance as a critical intersection where a person may jump out. Therefore, the navigation device 100 can guide the user to the point G73, G75, G77 as follows: “There may be people coming and going at this intersection. The shape of the intersection may be reflected in this guidance. For example, the navigation device 100 may change the direction such that “a person may come out from the right side” at the point G73, and “a person may come out from the left and right” at the points G75 and G77. Show and call attention.

The method of alerting may be changed according to the number of houses corresponding to the arrival point. The arrival point G73 and the point G75 in FIG. 10 correspond to two houses, whereas the arrival point G77 corresponds to three houses. Also good. For example, the content of a message to call attention may be changed, or it may be emphasized by a tone or volume of voice guidance, brightness of a screen display, color, or the like.

In the embodiment, an intersection having two or more houses is targeted for alerting (step S76 in FIG. 8). However, the number of houses can be arbitrarily set, and a larger number of houses may be used as a criterion value. If the judgment reference value is increased, the frequency at which guidance is performed decreases, and conversely, the user's attention when guidance is performed can be effectively evoked.

For guidance at a critical intersection, the navigation device 100 may obtain the density at which arrival points corresponding to a house appear along the route, and may set the content of information presentation for alerting according to the density. Good. When the points G77, G75, and G73 shown in FIG. 10 are relatively close to each other, when the navigation device 100 provides guidance that “a person may come out” at each intersection, the user is paralyzed by such guidance. This may reduce the effectiveness of alerting. Therefore, when there is an intersection requiring attention exceeding a predetermined density in this way, it may take a form of alerting the entire area such as “I will travel through an area where there is a risk of jumping out for a while”. When the navigation device 100 travels from the lower side to the upper side of the link L70 in FIG. 10, the navigation device 100 approaches the point G77, and as a comprehensive guide to the points G77, G75, G73, It alerts the whole.

As another aspect, when the density of the intersections requiring attention is high, the determination reference value (the value in step S76 in FIG. 8) for determining whether or not the intersection needs attention may be increased to make the determination criteria more strict. For the areas indicated by points G77, G75, and G73 in FIG. 10, the navigation device 100 changes the determination reference value to, for example, three houses. By doing so, since only the point G77 becomes a cautionary intersection, it is possible to avoid a situation in which alerting is frequently performed. As a specific processing mode, after executing the guidance target intersection setting process (FIG. 8), the navigation apparatus 100 calculates the density of the intersections requiring attention, and for areas where the density exceeds a predetermined value, step S76. A method of executing the guidance target intersection setting process (FIG. 8) again after increasing the determination reference value can be taken.

E. Modifications: In the examples, examples of virtual intersections and cautionary intersections have been shown, but the guidance of the examples can be applied in various modes depending on the type of arrival point. For example, when the arrival point corresponds to a restaurant or a store, the navigation device 100 provides guidance such as “There is a restaurant street on the right side” or “There is a store street” depending on the density. Also good. When performing a route search, if a purpose such as having a meal on the way to the destination is set, the navigation device 100 extracts an arrival point corresponding to the restaurant, and in the course of route guidance, "There is an Italian restaurant," you may present information according to the purpose. By presenting information according to the type of feature associated with the arrival point in this way, even if the feature is not selected as the destination by the user, Information that matches the intention can be presented.

In the embodiment, an example in which various information is presented after performing route guidance is shown. However, the present invention is applicable even when route guidance is not performed. For example, in FIG. 10, when the user is traveling on the link L70, the navigation device 100 detects the current position of the user, and “there is a possibility that a person will appear for the arrival point ahead of the user. Can be called. Even if the user's route is not known, the traveling direction can be determined from the change in the current position, so it is possible to easily determine whether the intersection is located ahead. When alerting by voice, the user may wait until a point at which the user can almost certainly pass through the intersection to be alerted. For example, consider a case where the user is traveling upward from the point G77 in FIG. The user may go straight through the point G75 or turn right or left here. If attention is paid to point G73 in such a situation, the user may be confused. However, after the user passes the point G75, it is clear that the user passes the point G73 unless it is a U-turn. As described above, the navigation device 100 can avoid the confusion of the user by taking the mode of delaying the guidance timing until it is determined that the passage is certain in consideration of the current position and the traveling direction of the user. . This determination is made by the navigation device 100 as to whether there is a branch or other arrival point between the arrival point G73, G72, G71 located in front of the user and the current position of the user (eg, point G75). Based on. While the arrival point G73 exists between the arrival points G71, G72 and the point G77, there is no branch or the like between the arrival point G73 and the point G75. In such a case, the navigation device 100 may determine that the possibility of passing through the arrival point G73 is high, and perform alerting. Attentions can be made not only by voice but also by display. For example, the navigation device 100 can take a form in which the arrival points G73, G72, etc. are displayed in a conspicuous color such as red depending on the degree of danger. In this way, when calling attention by display, there is a low possibility of causing confusion for the user, so it is also possible to target an arrival point within a predetermined range from the current position.

The present invention does not necessarily have all the functions of the above-described embodiments, and only a part may be realized. Moreover, you may provide an additional function in the content mentioned above. Needless to say, the present invention is not limited to the above-described embodiments, and various configurations can be adopted without departing from the spirit of the present invention. For example, a part configured in hardware in the embodiment can be configured in software and vice versa.

The present invention can also be configured as a route guidance method described below. For the network data representing roads as nodes and links, and for features including roads, the points on the road where the network data has been maintained as roads where vehicles can pass, and any road from the features This is a guidance method for presenting information that supports road traffic by a computer having a map database that stores feature data that stores data of arrival points, which are points that can be reached by traffic, and detects the current position. A route guidance method comprising: a detection step; and a guidance step of presenting information according to a type of a feature corresponding to the arrival point for a point where an arrival point having a predetermined positional relationship with the current position exists. .

Furthermore, you may comprise as a computer program shown below. For the network data representing roads as nodes and links, and for features including roads, the points on the road where the network data has been maintained as roads where vehicles can pass, and any road from the features A computer program for presenting information supporting road traffic by a computer having a map database that stores feature data for storing arrival point data, which is a point where traffic can be reached, A computer realizes a detection function to detect and a guidance function to present information according to the type of the feature corresponding to the arrival point for a point where an arrival point having a predetermined positional relationship with the current position exists It is a computer program for.

INDUSTRIAL APPLICABILITY The present invention can be used for route search to a destination that is off the network and route guidance that takes into account the presence of features at points outside the network.

DESCRIPTION OF SYMBOLS 100 ... Navigation apparatus 101 ... Main control part 102 ... Transmission / reception part 103 ... Command input part 104 ... GPS input part 105 ... Map database 106 ... Display control part 107 ... Path | route search part 200 ... Server 201 ... Transmission / reception part 202 ... Database management part 210 ... Map database storage unit 211 ... feature data 212 ... character data 213 ... network data 300 ... database generation device 301 ... main control unit 302 ... transmission / reception unit 303 ... command input unit 304 ... display control unit 305 ... map database storage unit 306 ... Database maintenance department 307 ... Arrival point calculation department

Claims (6)

A guidance system for presenting information to support road traffic, in which network data that represents a road on which a car can pass by nodes and links, and points on the network data associated with a first feature position detector for detecting a map database storing section, the current position to store a certain first point of arrival and a second of the second arrival point is the point on the network data associated with the feature data When the current position is within a predetermined distance range from the first arrival point, the first information is presented according to the type of the first feature corresponding to the first arrival point, A guide unit that presents second information according to the type of the second feature corresponding to the second arrival point when the current position is within a predetermined distance range from the second arrival point. Guidance system with
The guidance system according to claim 1, wherein an input unit that inputs a departure point and a destination, a route search unit that performs a route search from the departure point to the destination with reference to the network data, and The guidance unit further presents the route to the user to perform route guidance, and the first arrival point or the second arrival point on the route from the current position to the destination . A guidance system for presenting one information or presenting the second information.
3. The guidance system according to claim 1, wherein the route guidance unit corresponds to the first arrival when the first feature or the second feature is a parking lot or a parking space. guidance system relative to the point or points where the second point of arrival are present to guide the point of the first point of arrival or of the second point of arrival is present as an intersection.
The guidance system according to claim 3, wherein the route guidance unit is configured according to how the parking lots corresponding to the first arrival point or the second arrival point are arranged on the left and right sides of the route. Guide system to set the content of information presentation.
A claims 1-4 guidance system according to any one, the route guidance unit, the first feature or said second feature is in the case of housing, corresponding to the first feature A guidance system for presenting information that alerts a user to safe passage at a point where the second arrival point corresponding to the first arrival point or the second feature exists.
The guidance system according to claim 5, wherein
The route guidance unit, for the first point of arrival or said second arrival point corresponding to said housing, said first point of arrival or said defined by the number present in the predetermined range definitive said path first The guidance system which calculates | requires the density of the arrival point of 2 and sets the content of the information presentation for the said alerting according to this density.