JP2020046236A - Electronic device, route search method, and route search program - Google Patents

Abstract

To provide an electronic device, a route search method and a route search program with which it is possible to search for an appropriate guidance route and provide it taking into account the cost of exiting a node.SOLUTION: The route search program executed by the electronic device comprises the steps of: searching for a route from the present position or a discretionary point to a destination on the basis of map data; and setting the cost of exiting for each exit link, with a link for entering a node defined as an entry link and one or a plurality of links through which the node can be exited, defined as an exit link. The search step further calculates a traffic cost to the destination taking into account the set cost of exiting.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an electronic device having a navigation device, and more particularly to a technique for searching for a guidance route in consideration of a traffic cost at an intersection.

  A conventional typical in-vehicle navigation device detects the current position of a vehicle using an autonomous navigation sensor, a GPS (Global Positioning System) receiver, and the like, reads map data near the vehicle from a storage medium, and displays the map data on a screen. I do. Then, the current position of the vehicle can be known at a glance by superimposing and displaying the vehicle position mark indicating the vehicle position on a predetermined location on the screen.

  2. Description of the Related Art In-vehicle navigation devices are usually provided with a function (route guidance function) for providing guidance so that a user can easily travel on a road to a destination without making a mistake. According to this route guidance function, an optimal route (typically, the route with the lowest cost) from the departure point (typically, the current position of the vehicle) to the destination is searched using map data in a horizontal search. Method and the Dijkstra method are used to perform a simulation calculation and perform an automatic search. The searched route is stored as a guide route so that the guide route can be distinguished from other roads on a map image during traveling (for example, When the vehicle approaches a predetermined distance to an intersection where the course should be changed on the guidance route, the guide map of the intersection is displayed on the map image (by changing the color or increasing the line width). By displaying an enlarged view of the intersection, an arrow indicating the direction of travel at the intersection, the distance to the intersection, the name of the intersection, etc.), and which direction to travel at the intersection. User knows if it's okay It has been cut way.

  Note that the cost is a numerical value of the degree of suitability as a guidance route. The cost related to a node (a point expressed by latitude and longitude) and a link (a portion connecting two nodes, that is, a portion of a road) )). The cost of the link is based on the distance (road length) and is a coefficient determined based on certain rules according to the road type (road class) indicating whether it is a general road or an expressway, the number of lanes, the road width, etc. The value is a value (relative value) multiplied by a (weighted coefficient), a predicted travel time of the vehicle, or the like. On the other hand, the cost related to the node includes the number of directions in which other vehicles must be considered when passing through an intersection (hereinafter, referred to as a bill direction), the angle in the passing direction such as turning left and right, and the traffic light at the intersection. A value (relative value) multiplied by a coefficient (coefficient with predetermined weighting) determined based on a certain rule is set in accordance with the presence / absence of, for example.

  In a conventional in-vehicle navigation device, the calculation of a route to a destination is performed using a network in which actual roads to be traveled are abstracted into nodes and links. The "optimum route" to the destination is the sum of the link cost for each link from the departure point to the destination and the intersection passing direction cost for each node (that is, the total cost to the destination). Is a link string that minimizes the traffic cost.

  The traffic cost when passing through each link is calculated by, for example, the following equation (1).

Traffic cost = link cost + intersection passing direction cost ... (1)
Here, the link cost includes a road length, and is a value determined to be smaller as the road length between nodes is shorter. The intersection passing direction cost includes the number of billing directions, and is a value (relative value) determined based on a certain rule according to the number of directions in which another vehicle is to be considered when passing through the intersection. ) Is included. In the related art, the total traffic cost is obtained by adding the traffic cost based on the above equation (1) for each link from the departure point to the destination.

  As a technique related to such a route search, Patent Literature 1 discloses that a link evaluation value is calculated using a road width coefficient or a road type coefficient corresponding to a time, a day of the week, or the like, and the time / day of a route setting time is calculated.・ A technique for setting an appropriate route according to the date and time is described.

  Further, in Patent Document 2, in the route setting, if there is a traffic light installed at an intersection or if the installed traffic light is such that a right-turn arrow signal is displayed, the right-turn cost is reduced to a small value. A technique for setting and searching for a route that reduces the total value of the toll costs is described.

JP-A-2002-148065 JP 2005-321360 A

  As described above, in the conventional in-vehicle navigation device, basically, a route that minimizes the total traffic cost from the departure point to the destination is guided as a guidance route (recommended route).

  Here, FIG. 1 is a diagram showing the problem of the present invention. FIG. 1A specifically shows one of the problems of the present invention, in a case where there is a road (road link 2) prepared to enter the facility between the current location and the destination. It is. Note that G in FIG. 1A indicates a destination. Such road conditions include, for example, a rotary in front of a station. The nodes X and Y indicate intersections, and the road link 2 is one-way from the intersection X to the intersection Y. The road link 1 has the shortest road length among the links connecting the intersection X to the intersection Y.

  Here, when a route from the current position to the destination is searched, two routes as shown in FIG. 1B are calculated as candidates. Route 1 is the shortest distance route between the current location and the destination passing through the road link 1, and Route 2 is a route passing through the road link 2. The route 2 has a longer moving distance than the route 1, but the current navigation device has a longer moving distance and the route 2 that enters the facility road is selected as the guidance route.

  Here, the reason why the route 2 is selected will be described in detail with reference to FIG. 2 showing a method for setting the traffic cost at the intersection. FIG. 2A is a diagram schematically illustrating an intersection X in FIG. The link A is an entry link that enters the intersection X from the current position, and the links B, C, and D are exit links of the intersection X in the entry link A. That is, when the incoming link is the link A, the exit links are the three links B, C, and D. Arrows S11, S12, S21, S22, S31, S32, S41, and S42 indicate the direction of the account when passing through intersection X from approach link A. Note that the number of billing directions and the actual number of lanes are not the same, and the counting direction is a direction in which it is necessary to consider the traveling of other vehicles when passing through an intersection. In the following description, the link A, which is an entrance link, is referred to as an entrance link A, and the links B, C, and D which are exit links are referred to as exit links B, exit links C, and exit links D.

  FIG. 2B is a diagram showing the traffic costs of each of the exit links B, C, and D in the entrance link A. In the following description, the traffic cost on the escape link is referred to as the escape cost. The escape cost is set by the number in the account direction. For example, in the left turn direction of the exit link B, since the account direction is only S12, an escape cost 15 for one account direction is added. In addition, the value of the escape cost for one account direction may be changed depending on the embodiment. Next, since there are two account directions S12 and S21 in the straight traveling direction of the escape link C, an escape cost 30 for two account directions is added. Then, since there are three billing directions S12, S21, and S42 in the right turn direction of the escape link D, an escape cost 45 for three billing directions is added.

  FIG. 2C is a diagram illustrating a comparison of a total value of costs obtained by adding an exit cost and a link cost (cost based on distance) of an intersection from the current position to the destination at the intersection X. First, when the vehicle goes straight at the intersection X (route 2), the escape cost of the intersection X is set to 30, the link cost is set to, for example, 137 in consideration of the distance, and the same escape cost is calculated at the intersection Y. The escape cost is 30 according to the method, and the total value of the travel cost of the route 2 is 197. Next, at the intersection X, when making a right turn (route 1), the escape cost of the intersection X is set to 45, the link cost is set to, for example, 113 in consideration of the distance, and the same escape cost is calculated at the intersection Y. The escape cost is 45 according to the method, and the total value of the travel costs of the route 1 is 203. Therefore, since the route with the minimum traffic cost is automatically selected as the guidance route, the route of Route 2 having the low total value of the traffic costs is selected.

  The present invention is to solve such a conventional problem, and provides an electronic device, a route search method, and a route guidance program capable of searching for and providing an appropriate guide route in consideration of an escape cost of a node. With the goal.

  An electronic device according to the present invention is an electronic device having a navigation function, and includes an acquisition unit that acquires map data having nodes and links, and a current position or an arbitrary point based on the map data acquired by the acquisition unit. Route search means for searching for a route from a route to a destination, and obtaining link information of the exit link when the link entering the node is an entry link and one or more links that can escape from the node are exit links. Setting means for setting an escape cost for each of the escape links obtained from the means, and the route search means calculates a traffic cost to a destination in consideration of the escape cost set by the setting means. .

  In one embodiment, the setting means sets the escape cost according to the number of account directions that need to be considered when passing through the escape link, and includes at least one of the escape links connected to the node. Based on one piece of link information, when it is assumed that another vehicle cannot enter the intersection from the direction of the exit link, the exit cost is changed. In one embodiment, when at least one piece of link information among the escape links connected to the node is one-way, the setting unit changes the escape cost for each of the escape links. In one embodiment, when at least one link information among the escape links connected to the node is information related to the prohibition of traffic, the setting unit changes the escape cost for each of the escape links. In one embodiment, the setting unit acquires the number and / or type of lanes in the account direction from the acquisition unit, and sets an escape cost for each escape link in consideration of the number and / or type of the lanes. I do. In one embodiment, the route search unit further includes a determination unit that determines a guidance route from the plurality of searched routes, and the route search unit includes a link of a link set on a route from a current position to a destination. The traffic cost is calculated by sequentially adding the cost and the escape cost of the escape link set in consideration of the link information at each node, and the determining unit determines the route having the smallest traffic cost as the guide route. I do.

  A route search method according to the present invention is a route search method in an electronic device that executes a navigation function using map data having nodes and links, and based on the map data, a route from a current position or an arbitrary point to a destination. A step of searching for a route, and in a case where a link entering a node is an entry link and one or a plurality of links that can escape from the node is an exit link, an exit cost for each exit link based on link information of the exit link. And the searching step further includes a step of calculating a traffic cost to the destination in consideration of the set escape cost.

  A route search program according to the present invention is a route search program in an electronic device that performs a navigation function using map data having nodes and links, and based on the map data, a route search program from a current position or an arbitrary point to a destination. A step of searching for a route, and in a case where a link entering a node is an entry link and one or a plurality of links that can escape from the node is an exit link, an exit cost for each exit link based on link information of the exit link. And the searching step further includes a step of calculating a traffic cost to the destination in consideration of the set escape cost.

  According to the present invention, since the escape cost of each escape link is set based on the link information of the escape link, an optimal route from the current location to the destination can be provided as a guidance route.

It is a figure showing a subject of the present invention. It is a figure showing the setting method of the traffic cost of an intersection in the subject of the present invention. It is a block diagram showing composition of a navigation device concerning an embodiment of the present invention. It is a figure showing the contents of map data concerning an embodiment of the present invention. It is a figure showing the functional composition of the route search program concerning the embodiment of the present invention. 4 is a flowchart illustrating an operation of the navigation device according to the embodiment of the present invention. It is a figure showing the setting method of the traffic cost of the intersection concerning the embodiment of the present invention.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. The electronic device according to the present invention can be an in-vehicle device fixedly mounted on a moving body such as an automobile, or a portable computer device that can be carried into the moving body. Although the electronic device of the present invention has a navigation function, other functions such as a function of reproducing audio / video data, a function of receiving a television / radio broadcast, and a function of executing application software are integrated. It may be provided.

  The electronic device of the present invention has a navigation function, and uses map data to execute the navigation function. This map information may use map data stored in a storage medium such as a DVD-ROM, or acquire necessary map data from a distribution site or a distribution server via data communication means. There may be. In the following description, a vehicle-mounted device mounted on a vehicle will be described as an example of the electronic device.

  FIG. 3 is a block diagram illustrating a configuration of the vehicle-mounted device according to the embodiment of the present invention. The in-vehicle device 100 includes an input unit 110, a vehicle position detection unit 120, a communication unit 130, a voice output unit 140, a display unit 150, a storage unit 160, and a control unit 170.

  The input unit 110 allows a user to input various information to the in-vehicle device. The input unit 110 includes, for example, an input key device, a voice input recognition device, a touch panel, and the like. A user inputs a menu selection operation, a map scroll, a destination setting, a route search instruction, and the like via the input unit 110. be able to.

  The vehicle position detection unit 120 measures the current position of the vehicle. The own-vehicle position detection unit 120 detects the own-vehicle position by, for example, absolute position detection based on GPS positioning and relative position detection based on an autonomous navigation sensor. The autonomous navigation sensor includes, for example, an azimuth sensor such as an angular velocity sensor and a geomagnetic sensor, and a vehicle speed sensor such as a vehicle speed pulse sensor. In addition, the position information acquisition unit 110 may acquire the vehicle position information by accessing a position information distribution site or a distribution server via a network. Communication with the network at that time is performed via the communication unit 130.

  The communication unit 130 enables wired or wireless data transmission / reception with an external device or an external network. The communication unit 130 may include, for example, the vehicle-mounted device 100 having a built-in communication function, or may connect a terminal having such a communication function to the vehicle-mounted device 100. The communication unit 130 can access the distribution site (or the distribution server) and acquire the vehicle position information, the map data, and the detailed information on the charging facility via the network. Also, wired or wireless data communication using WiFi, LAN, infrared communication, telephone line, or the like is possible.

  The voice output unit 140 outputs voice guidance for guiding the route calculated by the control unit, and provides voice guidance of driving support information to the driver. The display unit 150 displays a road map based on the determined guidance route based on the execution of the route search program 200. The display unit 150 includes, for example, a display device such as a liquid crystal display, an organic EL display, and a projection display, and displays image data of a map, and displays a setting screen and a menu screen for performing user settings.

  The storage unit 160 stores a program and a database necessary for executing various navigation functions. In one embodiment, the storage unit 160 stores a map database 162, and the map database 162 includes map data, road data, facility data, and the like. Here, as the storage medium of the map database 162, a storage medium such as a DVD-ROM, a CD-ROM, and a hard disk may be used. In some embodiments, various map information may be obtained from outside via the communication unit 130 without using a storage medium.

  Here, the contents of data stored in the map database 162 will be described with reference to FIG. The map database 162 includes a road unit representing a road network, a drawing unit representing a place name and other objects other than roads to be displayed on a map, and an intersection unit. Here, in the road unit, a road network is defined as a set of nodes and links connecting the nodes. The road unit is provided with a node table including node information provided for each node, and a road table provided for each link. And a link table including link information. Note that nodes are always provided at road connection points such as intersections. Nodes are also provided at points where road types are different.

  Each node information includes a node number serving as an identifier of the corresponding node, node attributes representing various attributes of the corresponding node, node coordinates representing the position of the corresponding node, and a connection link representing a link connected to the corresponding node. Information, connection node information indicating another node connected to the corresponding node via one link, and a corresponding intersection number in which the intersection number of the intersection is registered when the node is a node constituting the intersection .

  Each link information includes a link number serving as an identifier of a corresponding link, a link attribute representing various attributes such as identification of a road representing a road section, and a node serving as one end point of the corresponding link. A first node number representing a node number of the first node, a second node number representing a node number of a second node which is a node corresponding to the other end point, a traffic direction representing a direction in which a vehicle can travel on the link, Connection link information indicating another link connected to the link.

  Here, if the link is a link indicating a section of a road that can travel in the up / down direction, bidirectional is registered as the traffic direction of the link information, and the link indicates a section of a one-way road. In this case, information indicating which one of the direction from the first node to the second node and the direction from the second node to the first node is the direction in which the vehicle can travel is registered. It should be noted that one road that can travel in the up / down direction is regarded as a set of two roads each having a traveling direction in the up / down direction, and a link that forms each road for each of the two roads. In this case, in the traffic direction of the link information of these links, the traveling direction of the road representing the road section corresponding to the link includes a direction from the first node to the second node, and a direction from the second node. Information indicating which of the directions toward the first node is the direction in which the vehicle can travel is registered.

  Next, the intersection unit has intersection data provided corresponding to each intersection, and each intersection data includes an intersection number which is an identification number of the intersection, an intersection attribute indicating the name of the intersection, and a node forming the intersection. A registered intersection configuration node table, an intersection connection link table in which links connecting to the intersection are registered, an intra-intersection link table in which links in the intersection are registered, and passage information are registered. Taking the enlarged view of the intersection X in FIG. 2A as an example, the links connected to the intersection at the intersection X are four links: link A, link B, link C, and link D.

  Next, exit information for each entry link is stored in the passage information of the intersection data. Taking the enlarged view of the intersection X in FIG. 2A as an example, when the incoming link is the link A, the outgoing links are stored as the link B, the link C, and the link D. In one embodiment, at the same time as the exit link is stored, the passing direction of the exit link with respect to the entrance link is also stored. That is, the escape link B may be stored in association with the left turn direction, the escape link C may be stored in the straight ahead direction, and the escape link D may be stored in the right turn direction.

  Next, the control unit 170 includes a microcontroller or a microprocessor having a ROM / RAM or the like, executes a predetermined process based on a control program stored in the ROM or the RAM, and executes the operation of each unit of the in-vehicle device 100. Control. The control program according to the present embodiment includes a route search program 200.

  The control unit 170 executes the route search program 200. FIG. 5 is a diagram showing a functional configuration of the route search program 200 according to the embodiment of the present invention. The route search program 200 includes an intersection identification unit 202, an entry link identification unit 204, an exit link identification unit 206, a link information acquisition unit 208, an exit cost setting unit 210, a traffic cost calculation unit 212, and a guidance route determination unit 214. .

  The intersection specifying unit 202 specifies an intersection that may possibly pass in a route search from the current location to the destination. The entry link identification unit 204 identifies a link that enters the intersection specified by the intersection specification unit 202. The exit link identification unit 206 identifies the exit link for the entrance link at the specified intersection by the intersection specifying unit 202. In addition, the passing direction (left turn, straight ahead, right turn) for the incoming link is also identified for each exit link.

  The link information acquisition unit 208 acquires link information on the escape link identified by the escape link identification unit 206. In the present embodiment, link information is obtained from a link table stored in a map database. In one embodiment, the information may be obtained from the outside via the communication unit 130. The escape cost setting unit 210 sets an escape cost for each escape link based on the link information of the escape link. In the present embodiment, the value of the escape cost for each escape link is changed when any one of the escape links is one-way in the direction of exiting the intersection.

  The traffic cost calculation unit 212 calculates a total of at least the set escape cost and the cost including the link cost to the destination. The guidance route determination unit 214 determines a route that minimizes the total traffic cost as a guidance route (recommended route), and performs route guidance.

  The operation of the navigation device according to the embodiment of the present invention will be described with reference to the flowchart of FIG. 6 and a diagram illustrating a method of setting a traffic cost at an intersection according to the embodiment of the present invention of FIG. FIG. 7 shows the same traffic situation as in FIG. 1, and FIG. 7A is a diagram schematically showing the intersection X in FIG. The link C in FIG. 7A has one-way link information in the escape direction from the intersection X. First, a destination is set according to an instruction from a user (S100). When the destination is set, the route search program 200 starts (S102). The route search is, for example, using link data and node data stored in the map database 162, and in a continuous link from the current location or a designated point to the destination, the sum of the link costs of each link is minimized. Search for a route that becomes In the process, first, the intersection specifying unit 202 specifies an intersection (node) where a traffic is assumed (S104). Here, when the intersection is not specified (the intersection is not included on the route), the process proceeds to S114 described later. When the intersection is specified, the process proceeds to S106. In FIG. 7A, the intersection X is specified.

  For the specified intersection, the entry link identification unit 204 and the entry link identification unit 206 identify the entry link at each intersection and the exit link for the entry link (S106). In FIG. 7A, the incoming link is identified by link A, and the exit link is identified by link B, link C, and link D. The link information acquisition unit 208 acquires link information on the identified escape link from the map database 162 (S108). In FIG. 7A, link information of link B, link C, and link D is obtained.

  Next, the escape cost setting unit 210 determines whether there is an escape link having link information that satisfies the condition among the escape links at the intersection (S110). The condition is link information indicating that another vehicle does not enter the intersection from the direction of the exit link. In the present embodiment, it is determined whether or not the vehicle is one-way in a direction to escape from the intersection. That is, in FIG. 7A, as in the present embodiment, when the link C is one-way among the links B, C, and D, there is an escape link having link information that matches the condition. And the process moves to S112. If there is no escape link having link information that matches the condition among the links B, C, and D, the process proceeds to S114.

  The escape cost setting unit 210 sets an escape cost according to the number in the account direction. The setting values are set as defaults and set according to the number of account directions. For example, as shown in FIG. 2, when the vehicle turns left and passes through the escape link B, the number of directions is one, and the escape cost to the escape link B is set to 15. In the straight-ahead direction, the number of directions is two, and the escape cost to the escape link C is set to 30. In the right turn, the number of directions to the escape link D is three, and the escape cost to the escape link D is set to 45. However, in S110, if there is an escape link having link information that matches the condition, the escape cost setting unit 210 changes the default value of the escape cost (S112).

  As shown in FIG. 7A, when the exit link C is a one-way street, there is no other vehicle entering the intersection X from the exit link C, so that it is not necessary to count S42. Here, FIG. 7B is a diagram showing the traffic costs of each of the exit links B, C, and D in the entrance link A. As shown in FIG. 7B, the escape cost varies. First, when the vehicle turns left and passes through the escape link B, since the account is not originally counted in S42, the account direction is set to one (S12) and the escape cost is set to 15. Even in the straight-ahead direction, since S42 is not originally counted, the number of account directions is two (S12, S21) and the escape cost is set to 30. In the case of a right turn, the number of account directions is originally three (S12, S21, S42), but since S42 is excluded because it is not necessary to count, the number of account directions is two (S12, S21), and the escape cost changes to 30. Is set.

  If there is no escape link having link information that matches the condition, the default escape cost is set as it is (S114). The traffic cost calculation unit 212 adds the costs to reach the destination, such as the link cost based on the distance of the road and the traffic costs at other intersections, to the escape cost set in S112 or S114. Then, the total value of the toll costs is calculated (S116). The escape costs at the intersections X and Y are calculated by the above-described methods. The link costs of the road link 1 and the road link 2 are determined according to the distance. For example, it is assumed that the road link 1 is set to 113 and the road link 2 is set to 137.

  FIG. 7C is a diagram showing details of the traffic costs applied to each of Route 1 and Route 2 and the total value. First, since the route 2 travels straight at the intersection X, the traffic cost becomes 30. Thereafter, the traffic cost 137 for traveling on the road link 2 is added, and the traffic cost 30 for traveling straight on the intersection Y is further added. Therefore, the total of the traffic costs is 197. Next, the route 1 is a right turn at the intersection X, and as described above, the account direction decreases, so that the toll cost changes to 30, and thereafter, the toll cost 113 for traveling on the road link 1 is added. A traffic cost 45 is added to go straight on at the intersection Y. Therefore, the total of the traffic costs is 188.

  Next, the guide route determination unit 214 determines, as a guide route (recommended route), a route that minimizes the total traffic cost calculated by the traffic cost calculation unit 212 (S118). Comparing the total values of route 1 and route 2 in FIG. 7C, route 1 has a smaller total traffic cost than route 2 and no route candidate with a smaller value exists. 1 is determined as a guidance route (recommended route).

  According to the above-described embodiment, a circuitous route (route 2) via a road provided for intrusion into the facility has been selected as a guidance route based on the total traffic cost as shown in FIG. 2C. However, by setting the escape cost in consideration of the link information of the escape link at the intersection, as shown in FIG. 7 (c), the vehicle does not go through the road maintained for entering the facility, In addition, the shortest distance route (route 1) to the destination is selected as the guidance route. This makes it possible to provide the user with a route that is the shortest distance to the destination and does not enter a road such as a facility.

  In the above embodiment, the value of the escape cost is changed when one-way is present in the escape link. However, in one embodiment, construction and temporary traffic regulation may be performed in addition to the one-way. When information on traffic prohibition such as traffic prohibition due to an accident is acquired, the vehicle may not enter from the direction of the acquired escape link, and the escape cost may be similarly varied. Further, the present invention is applicable even when there are a plurality of escape links that satisfy the above-mentioned conditions among the escape links, and the escape cost can be set in consideration of the account direction.

  Furthermore, in the description of the present embodiment, the escape cost is set by paying attention only to the number of the directions, but in one embodiment, the number of the lanes of the escape link for each direction of the account and the number of the lanes of the relevant lane are determined. The escape cost may be set in consideration of the type. For example, if S21 in FIG. 7 is composed of two lanes, a left-turn lane and a straight-ahead right-turn lane, the exit link C has an escape cost value that takes into account the two lanes of S21. Under the same conditions, the exit link D has one lane for the vehicle coming from the direction of the link B, so that the exit cost value for one lane is added. decide. In this way, by setting the escape cost in consideration of the number of lanes and the type of lane, it is possible to calculate a more optimal route.

  In the present embodiment, the route search program 200 is executed by the on-vehicle device 100 mounted on the car. However, the present invention is not limited to this. The external server may execute the route search program 200, receive the searched guidance route from the communication unit 130, and perform route guidance in the vehicle-mounted device 100 based on the received guidance route.

  Further, the minimum cost route to the destination may be calculated by using the present invention in combination with another route search technique.

  Although the preferred embodiment of the present invention has been described in detail, the present invention is not limited to a specific embodiment, and various modifications and changes may be made within the scope of the invention described in the appended claims. It is possible.

X, Y: intersection
S11, S12, S21, S22, S31, S32, S41, S42: Account direction 100: In-vehicle device 110: Input unit 120: Own vehicle position detection unit 130: Communication unit 140: Voice output unit 150: Display unit 160: Storage unit 162: Map DB
170: control unit

Claims (8)

An electronic device having a navigation function,
Acquisition means for acquiring map data having nodes and links;
Route search means for searching a route from a current position or an arbitrary point to a destination based on the map data acquired by the acquisition means;
When a link entering a node is an entry link, and one or a plurality of links that can escape from the node is an exit link, link information of the exit link is acquired from the acquisition unit, and an exit cost is calculated for each exit link. Setting means for setting;
The electronic device, wherein the route searching means calculates a traffic cost to a destination in consideration of the escape cost set by the setting means. The setting means sets the escape cost according to the number of account directions that need to be considered when passing through the escape link, and sets at least one of the escape links connected to the node to link information. The electronic device according to claim 1, wherein the escape cost is changed when it is assumed that another vehicle cannot enter the intersection from the direction of the escape link. The electronic device according to claim 2, wherein the setting unit changes the escape cost for each of the escape links when at least one of the escape links connected to the node is one-way. The electronic device according to claim 2, wherein the setting unit changes the escape cost for each of the escape links when at least one link information among the escape links connected to the node is information relating to the passage prohibition. . The said setting means acquires the number and / or type of the lane in the said account direction from the said acquisition means, and sets the escape cost for each of the escape links in consideration of the number and / or type of the lane. 5. The electronic device according to any one of items 4 to 4. The route searching means further includes a determining means for determining a guidance route from the plurality of searched routes, wherein the route searching means includes: a link cost of a link set on a route from a current position to a destination; The traffic cost is calculated by sequentially adding the escape cost of the escape link set in consideration of the link information in the above, and the determining means determines the route having the minimum traffic cost as the guidance route. 6. The electronic device according to any one of items 5 to 5. A route search method in an electronic device that performs a navigation function using map data having nodes and links,
Searching for a route from the current position or any point to the destination based on the map data;
Setting an exit cost for each of the exit links based on link information of the exit links, when a link entering the node is an entrance link, and one or more links that can exit from the node are exit links,
A route search method further comprising: calculating a traffic cost to a destination in consideration of the set escape cost. A route search program in an electronic device that performs a navigation function using map data having nodes and links,
Searching for a route from the current position or any point to the destination based on the map data;
Setting an exit cost for each of the exit links based on link information of the exit links, when a link entering the node is an entrance link, and one or more links that can exit from the node are exit links,
A route search program, further comprising a step of calculating a traffic cost to a destination in consideration of the set escape cost.

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