JP2013190266A - Navigation device and navigation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a navigation device and a navigation method, which are capable of obtaining map information economically by limiting usage of a mobile phone line while considering the memory space for the map information on the navigation device side.SOLUTION: A navigation device includes first communication means 7, storage means 11, path guidance means 24, and communication control means 25 so that the device guides to the destination by repeating the steps of: obtaining new map information, by the communication control means 25 via the first communication means 7, from a server 3 via an access point; and guiding a route, by the path guidance means 24, to a new access point included in the new map information. In the process, obtaining of map information having an information volume within the memory space of the storage means 11 is repeated.

Description

  The present invention relates to a navigation device and a navigation method, and more particularly to a navigation device and a navigation method suitable for performing route guidance to a destination based on map information acquired from a server.

  2. Description of the Related Art Conventionally, in a communication navigation device including a mobile terminal equipped with a navigation function such as Google (registered trademark) Map, a necessary map data is stored in a server without almost having map data on the navigation device side. From time to time was downloaded.

  In the past, downloading of such map data was generally performed by communication with a server via a mobile phone line, but recently, wireless communication has been performed by using a Wi-Fi function installed in a mobile terminal. Map data can be downloaded via a fixed line via a LAN access point.

  As a conventional technique related to downloading map data through such an access point, for example, a technique disclosed in Patent Document 1 is known.

JP 2004-198315 A

  By the way, in a region that can move to other countries on land such as Europe, the destination of navigation may be outside the country.

  In such a case, there is a problem that roaming occurs by moving outside the country where the cellular phone usage contract is made, and the data communication cost required for downloading the map data via the cellular phone line is high. It was happening.

FIG. 5 schematically shows such a problem. In other words, as shown in the figure, when using the mobile phone line only to download the map data D ₁ and D ₂ when going from the departure place to the destination outside the country, it could not be downloaded or saved at the time of departure. for map data D ₂ of the country, there was a need to download a roaming in the local.

  In this connection, in data communication via mobile phone lines, there is often an upper limit on the amount of data that can be communicated at a fixed amount every month, so data communication exceeding the upper limit is performed. If this happens, additional data communication costs have been incurred.

  On the other hand, map data can be downloaded without using a mobile phone line in an environment where the Wi-Fi function can be used such as at home, but the memory / storage capacity of the mobile terminal is limited. Therefore, all necessary map data may not be downloaded and held in advance. This is especially true when the destination is far away, such as abroad.

  Note that Patent Document 1 discloses a technique for reducing communication costs by downloading map data via a fixed line at an access point, but for an optimal download method considering the storage capacity of a mobile terminal, No effective proposal has been made.

  Therefore, the present invention has been made in view of the above points, and it is efficient to obtain economical map information while suppressing the use of a mobile phone line while considering the storage capacity of map information on the navigation device side. It is an object of the present invention to provide a navigation device and a navigation method that can be performed in the same manner.

  In order to achieve the above-described object, a navigation device according to the present invention includes a first communication between a current position detecting unit that detects a current position, a destination setting unit that sets a destination, and a server via an access point. First communication means for obtaining map information from the server, second communication means for obtaining map information from the server by second communication with the server via a mobile phone line, and the first Storage means for storing the map information acquired by the communication means or the second communication means, and the destination set by the destination setting means based on the map information stored in the storage means A navigation device including route guidance means for performing route guidance of the vehicle, when the destination is set by the destination setting means, up to the destination Based on the searched reference optimum route, the current position detected by the current position detection means, and the storage capacity information of the storage means, the first communication means and the second communication means One communication means capable of communicating with the server is map information corresponding to a region ahead in the traveling direction along the reference optimum route with respect to the current position, and the amount of information within the storage capacity of the storage means Communication control means for acquiring the map information from the server, the route guidance means to the access point included in the map information based on the map information acquired from the server by the communication control means The communication control means performs the route guidance to the access point by the route guidance means so that the current position is Triggered by reaching the point, the first communication means corresponds to a region on the front side in the traveling direction along the reference optimum route with respect to the access point by the first communication via the access point. New map information that is map information and has an information amount within the storage capacity of the storage means is acquired from the server, and acquisition of the new map information via the access point by the communication control means is obtained. And the route guidance to the new access point included in the new map information by the route guidance unit is repeatedly performed until the destination is included in the new map information, and the new map When the destination is included in the information, the destination based on the new map information is obtained by the route guidance unit. It is characterized by performing route guidance to.

  Further, the navigation method according to the present invention stores the map information acquired from the server by the first communication with the server via the access point or the second communication with the server via the mobile phone line. A navigation method for guiding a route to a set destination based on the map information stored in the storage means and when the destination is set by the navigation device A first step of searching for a reference optimum route to the destination, the reference optimum route searched in the first step, a current position of the navigation device, and storage capacity information of the storage means Based on the current position by the executable one of the first communication and the second communication. A second step of distributing map information corresponding to a region on the front side in the traveling direction along the sub-optimal route, the map information having an information amount within the storage capacity of the storage means from the server to the navigation device; And a third step of guiding the route to the access point included in the map information on the navigation device side based on the map information distributed in the second step, and the third step The direction of travel along the reference optimum route for the access point by the first communication via the access point when the current position has reached the access point by route guidance to the access point in Map information corresponding to the area on the front side, the amount of information within the storage capacity of the storage means A new step of distributing the new map information from the server to the navigation device, the distribution of the new map information via such an access point, and the new map information included in the new map information A fifth step in which route guidance to the access point is repeatedly performed until the destination is included in the new map information, and the destination is included in the new map information And a sixth step of guiding the route to the destination based on the new map information on the navigation device side.

  According to the present invention as described above, it is possible to obtain new map information from the server via the access point and return to the destination while repeating route guidance to the new access point included in the acquired new map information. Therefore, it is possible to efficiently acquire map information via the access point while considering the storage capacity of the storage means.

  Furthermore, in the navigation device of the present invention, when the destination is set by the destination setting unit, the communication control unit is configured such that both the first communication unit and the second communication unit are connected to the server. If communication is possible, the first communication means may be used to acquire the map information. Similarly, in the navigation method of the present invention, the second step includes the first step when both the first communication and the second communication are executable when the destination is set. The communication may be used for distributing the map information.

  And according to such this invention, since the map information at the time of destination setting can be acquired via an access point, acquisition of map information can be performed further economically.

  Furthermore, in the navigation device according to the present invention, when the map information acquired by the communication control unit includes a plurality of the access points, the route guidance unit includes the current one of the plurality of access points. Route guidance from the position to the access point existing at the farthest position on the front side in the traveling direction along the reference optimum route may be performed. Similarly, in the navigation method of the present invention, when the map information distributed from the server includes a plurality of access points, the third step and the fifth step include the plurality of access points. It may be a step of performing route guidance from the current position to the access point existing at the furthest position on the front side in the traveling direction along the reference optimum route.

  According to the present invention, map information reaching the area as close to the destination as possible at the access point can be acquired while considering the storage capacity of the storage means. As a result, communication costs can be further reduced.

  In the navigation device of the present invention, the reference optimum route is searched on the navigation device body side or on the server side where the current position and the destination information are acquired from the navigation device body, The navigation device main body includes an access point search unit that searches for the access point included in the map information when the destination is not included in the map information acquired by the communication control unit, and the access point search unit A route setting unit that automatically sets the access point detected by the route point to be routed to the destination, and an optimum route to the access point set as the route point by the route point setting unit. And searching based on the map information acquired by the communication control means. And a route searching unit that, the route guidance unit, in accordance with the optimum route searched by the route searching unit may perform a route guidance to the access point. Similarly, in the navigation method of the present invention, the first step is a step performed on the navigation device side or on the server side that acquires the current position and destination information from the navigation device, and the second step Or the seventh step of searching the access point included in the map information on the navigation device side when the destination is not included in the map information distributed in the step or the fourth step, and An eighth step of automatically setting the access point detected in the seventh step as a transit point to be routed to the destination on the navigation device side, and setting as a transit point in the eighth step The optimal route to the access point that has been determined is the second step or the second step And a ninth step of searching on the navigation device side based on the map information distributed in the step of, wherein the third step and the fifth step are searched for in the ninth step. It may be a step of performing route guidance to the access point according to the optimum route.

  According to the present invention, the navigation device side obtains from the server side by searching for the access point based on the map information obtained from the server and searching for the optimum route to the detected access point. The obtained map information can be used effectively on the navigation device side.

  Alternatively, in the navigation device of the present invention, the reference optimum route is searched on the navigation device body side or the server side where the current position and the destination information are acquired from the navigation device body, When the destination is not included in the map information to be acquired by the navigation device body, the server searches for the access point included in the map information, and sends the detected access point to the destination. Automatically set to the waypoint to be routed, search for the optimum route to the access point set to this route point based on the map information to be acquired by the navigation device body, the route guidance means, According to the optimum route searched by the server, the access point Route guidance and may be carried out in. Similarly, in the navigation method of the present invention, the first step is a step performed on the navigation device side or on the server side that acquires the current position and destination information from the navigation device, and the second step Or when the destination is not included in the map information to be distributed in the step or the fourth step, a seventh ′ step for searching the access point included in the map information on the server side; and 8th step of automatically setting the access point detected in the 7 'step as a waypoint to be routed to the destination on the server side, and a waypoint in the 8' step In the second step or the fourth step. A 9 ′ step of searching on the server side based on the map information to be distributed, wherein the third step and the fifth step are the optimum searched in the 9 ′ step. It may be a step of performing route guidance to the access point according to the route.

  According to the present invention, the server side searches for the access point based on the map information to be distributed to the navigation device and searches for the optimum route to the detected access point. The processing burden can be reduced.

  ADVANTAGE OF THE INVENTION According to this invention, economical map information acquisition which suppressed use of a mobile telephone line can be efficiently performed in consideration of the storage capacity of map information on the navigation device side.

The block diagram which shows embodiment of the navigation apparatus which concerns on this invention The block diagram which shows the main control part of the navigation apparatus of FIG. The schematic diagram which shows the operation example of the navigation apparatus of FIG. The flowchart which shows embodiment of the navigation method concerning this invention Explanatory drawing for demonstrating the problem of the conventional navigation apparatus

(Embodiment of navigation device)
Hereinafter, an embodiment of a navigation device according to the present invention will be described with reference to FIGS. 1 to 3.

  FIG. 1 is a configuration diagram illustrating a navigation system 1 including a navigation device according to the present embodiment.

  As shown in FIG. 1, a navigation system 1 is roughly divided into a communication type navigation device 2 mounted on a vehicle, and a server 3 that can be connected to the navigation device 2 via a communication network 4 such as the Internet. And is composed of. The navigation device 2 may be a portable terminal having a navigation function.

  First, the navigation device 2 will be described in detail. As shown in FIG. 1, the navigation device 2 has a navigation CPU 5. The navigation CPU 5 performs various processes and controls for navigation by executing a predetermined execution program.

  As shown in FIG. 1, the navigation CPU 5 is connected with a wireless LAN communication unit 7 as a first communication means. The wireless LAN communication unit 7 acquires map data from the server 3 by communication (first communication) with the server 3 via the wireless LAN access point 8 and the communication network 4 connected to the wireless LAN access point 8 via a fixed line. It is possible.

  Further, as shown in FIG. 1, a mobile phone line communication unit 10 as a second communication means is connected to the navigation CPU 5. The mobile phone line communication unit 10 can acquire map data from the server 3 by communication (second communication) with the server 3 via the communication network 4 via the mobile phone line.

  Furthermore, as shown in FIG. 1, the navigation CPU 5 is connected to a navigation-side map storage unit 11 as a storage means. The navigation-side map storage unit 11 stores map data acquired from the server 3 by the wireless LAN communication unit 7 or the mobile phone line communication unit 10. The navigation side map storage unit 11 may be realized by an SD memory or the like.

  Here, the map data includes, for example, various physical data frames such as a road data frame, a background data frame, a name data frame, a route guidance data frame, a route calculation data frame, a point information frame, and an audio data frame. .

  Of these, the road data frame is used for displaying a road map. In this road data frame, a link column data record is stored. This link column data record includes a link column header, link column shape information indicating the shape of the link column, and nodes / links indicating relationships with other link columns. It consists of link connection information, node additional information (link ID, width / lane information, road name, etc.), altitude information, traffic regulation information, and the like.

  The background data frame is used for displaying a background map. In this background data frame, a graphic data list column organized for each display class is stored, and each graphic data list further includes element point coordinate information for expressing the shape of a graphic (line or surface). (Start point coordinates, offset coordinates, etc.) are stored.

  Further, the name data frame is used for displaying a character string on a map. In this name data frame, a name data list collected for each display class is stored, and this name data list is composed of a name data record string. Each name data record corresponds to character data for displaying characters on a map. The character string displayed using this name data frame is the name of the display target feature for each display class, such as a building name, park name, administrative division name, and river name.

  Furthermore, the route guidance data frame is used for route guidance, and the route guidance data frame stores a guidance data frame, a character string data frame, a shape data frame, a pattern data frame, and the like. . Here, an intersection name, a road name, a direction name, a spot guide, a direction guide, and the like are stored in the guidance data frame. The character string data frame stores actual display characters, pronunciation characters, accent information, and the like related to the guidance data frame. Further, the shape data frame stores a shape for drawing an entity related to the guidance data frame. Furthermore, the pattern data frame stores actual data for drawing an image corresponding to the approach direction of the intersection for guidance.

  Further, the route calculation data frame is used for route calculation such as calculation of the optimum route to the destination, and this route calculation data frame includes a node data frame, a link data frame, a link cost data frame, An upper level node / link correspondence data frame, a node coordinate data frame, and the like are stored. Here, in the node data frame, for example, node data is stored in units of rank in which a plurality of road types are collected. The link data frame stores a link record, a regulation record, an inter-link cost record, and the like. Further, the link cost data frame stores the link ID, the cost of the link itself, and the like. Furthermore, in the data frame corresponding to the upper level node / link, information for specifying an upper node and a link based on the level is stored. The node coordinate data frame stores the coordinates of the node.

  Further, point information is stored in the point information frame. This point information is used for searching for a candidate for a destination or waypoint, displaying a POI (Points Of Interests) icon (in other words, a landmark) on a map, and the like. . Specifically, the point information includes a point name, a position (longitude and latitude), an address, a postal code, a telephone number, a type, a POI icon, and the like.

  In this embodiment, the point information includes information (name, position (coordinates), address, etc.) of the wireless LAN access point 8 such as a Wi-Fi spot. The access point 8 may be installed in a service area, a parking area, or the like.

  As shown in FIG. 1, a navigation side main storage unit 12 is connected to the navigation CPU 5. The navigation-side main storage unit 12 is used for storing an execution program of the navigation CPU 5, temporarily storing processing results of the navigation CPU 5, and the like. The navigation-side main storage unit 12 may be realized by a ROM, a RAM, or the like.

  Further, as shown in FIG. 1, a satellite navigation receiver 14 is connected to the navigation CPU 5. The satellite navigation receiver 14 receives a positioning signal including information on an orbit and time distributed from a positioning satellite (for example, a GPS satellite) (not shown), and inputs the received positioning signal to the navigation CPU 5. Yes.

  Furthermore, as shown in FIG. 1, a display 16 is connected to the navigation CPU 5 via an image interface (I / F) 15. On the display 16, various images generated by the navigation CPU 5 are output and displayed by the navigation CPU 5.

  As shown in FIG. 1, a speaker 18 is connected to the navigation CPU 5 via a voice interface (I / F) 17. From the speaker 18, various sounds are output by the navigation CPU 5.

  Further, as shown in FIG. 1, an input operation unit 20 is connected to the navigation CPU 5 via a user interface (I / F) 19. The user can perform various input operations for navigation on the navigation CPU 5 by using the input operation unit 20. The input operation unit 20 may be a touch panel of the display 16 or the like.

  Next, the navigation CPU 5 will be described in more detail. As shown in FIG. 2, the navigation CPU 5 has a current position calculation unit 22 as current position detection means as one of its functional blocks. The current position calculation unit 22 receives a positioning signal output from the satellite navigation receiver 14. The current position calculation unit 22 performs satellite navigation that calculates (detects) the current position of the navigation device 2 as an absolute coordinate based on the input positioning signal.

  As shown in FIG. 2, the navigation CPU 5 has a destination setting unit 23 as destination setting means as one of its functional blocks. The destination setting unit 23 displays various operation screens for setting a destination on the display 16 and then sets a destination according to the operation result of the input operation unit 20 for the displayed operation screen. It has become.

  Furthermore, as shown in FIG. 2, the navigation CPU 5 has a route guidance unit 24 as route guidance means as one of its functional blocks. The route guidance unit 24 guides the route to the destination set by the destination setting unit 23 based on the map data stored in the navigation-side map storage unit 11. The route guidance may be performed by displaying an enlarged view of an intersection, an enlarged view of a junction, or the like on the display 16, or by voice guidance or the like at the intersection via the speaker 18.

  Furthermore, as shown in FIG. 2, the navigation CPU 5 has a communication control unit 25 as a communication control means as one of its functional blocks. When the destination is set by the destination setting unit 23, the communication control unit 25 is one of the communication units 7 that can communicate with the server 3 among the wireless LAN communication unit 7 and the mobile phone line communication unit 10. 10 is made to communicate with the server 3 to acquire (download) map data (hereinafter referred to as original map data) from the server 3. This initial map data acquisition includes the reference optimum route to the destination searched on the navigation device 2 side or the server 3 side, the current position calculated by the current position calculation unit 22, and the navigation side map storage unit 11. Based on the storage capacity information. Further, the initial map data is map data corresponding to an area on the front side in the traveling direction along the reference optimum route with respect to the current position, and has map data having a data amount within the storage capacity of the navigation side map storage unit 11; Has been. Of course, the size of the area corresponding to the original map data depends on the storage capacity of the navigation-side map storage unit 11. Such acquisition of the initial map data is performed by the communication control unit 25 using the one communication unit 7, 10 to the server 3 for the destination and current position information and the navigation side map as necessary. The request for the initial map data accompanied by the transmission of the storage capacity information of the storage unit 11 and the reference optimal route information may be made, and the distribution of the initial map data from the server 3 in response to this request may be realized. . However, when the reference optimal route is calculated on the server 3 side, it is not necessary to transmit information on the reference optimal route, and the server 3 knows the storage capacity of the navigation-side map storage unit 11 in advance. Therefore, it is not necessary to transmit the storage capacity information of the navigation-side map storage unit 11. In addition, the reference optimum route may be an optimum route to a destination with a search condition that the route is not routed (a route with the lowest cost according to the search condition). The reference optimum route search condition may be configured to be set by an operation of the input operation unit 20. Furthermore, when searching for the reference optimum route on the navigation device 2 side, simple (rough detail) map data that can withstand the search for the reference optimum route is stored in the navigation-side map storage unit 11 or the like. You can keep it in

  And the communication control part 25 memorize | stores the initial map data acquired from the server 3 in this way in the navigation side map memory | storage part 11. FIG.

  As shown in FIG. 2, the navigation CPU 5 has an access point search unit 27 as an access point search means as one of its functional blocks. This access point search unit 27, when the destination is not included in the initial map data acquired by the communication control unit 25 (that is, when the destination does not belong to the area corresponding to the original map data) Based on the original map data, the access point 8 included in the original map data is searched.

  Furthermore, as shown in FIG. 2, the navigation CPU 5 has a waypoint setting unit 28 as a waypoint setting means as one of its functional blocks. The waypoint setting unit 28 automatically sets the access point 8 detected by the access point search unit 27 as a waypoint where the host vehicle should stop (should pass) before reaching the destination. ing.

  Furthermore, as shown in FIG. 2, the navigation CPU 5 has a route search unit 29 as route search means as one of its functional blocks. The route search unit 29 searches for an optimal route to the access point 8 set as a route point by the route point setting unit 28 based on the initial map data acquired by the communication control unit 25. . For searching for the optimum route to the access point 8, a known route calculation method such as Dijkstra method may be used. Further, the route calculation function of the route search unit 29 may be used for searching for the reference optimum route.

  Then, the route guiding unit 24 performs route guidance to the access point 8 according to the optimum route to the access point 8 searched by the route searching unit 29 in this way.

  Further, when the current position reaches the access point 8 by route guidance to the access point 8 as described above, the communication control unit 25 determines the arrival determination by the route guidance unit 24 and the calculation result of the current position calculation unit 22. The detection is based on the above. Then, triggered by this detection, the communication control unit 25 causes the wireless LAN communication unit 7 to acquire new map data from the server 3 through communication with the server 3 via the access point 8. . The new map data to be acquired at this time is map data corresponding to an area on the front side in the traveling direction along the reference optimum route with respect to the access point 8, and the data amount within the storage capacity of the navigation side map storage unit 11 It is supposed to have map data. Such acquisition of new map data may be performed in the same manner as the acquisition of the initial map data (request to the server 3 and response from the server 3). The acquired new map data is overwritten and saved in the navigation-side map storage unit 11 by the communication control unit 25, and the original map data is deleted.

  In the present embodiment, the acquisition of new map data via the access point by the communication control unit 25, the route guidance to the new access point 8 included in the new map data by the route guidance unit 24, and Is repeated until the destination is included in the new map data. At this time, a new access point 8 included in the new map data is searched by the access point search unit 27.

  When the destination is included in the new map data while repeating the acquisition of the new map data and the route guidance to the new access point 8 included in the map data, The route search unit 29 searches for the optimum route from the current position to the destination based on the new map data. The route guidance unit 24 performs route guidance according to the optimum route to the destination searched in this way.

  Next, the server 3 will be described in detail. As shown in FIG. 1, the server 3 has a server-side CPU 31. The server-side CPU 31 performs various processes and controls for distributing map data to the navigation device 2 by executing a predetermined execution program.

  As shown in FIG. 1, a server side communication unit 32 is connected to the server side CPU 31. The server-side communication unit 32 distributes map data to the navigation device 2 via a fixed line when the wireless LAN communication unit 7 accesses through the wireless LAN access point 8. It has become. The map data distributed in this way is, of course, received by the wireless LAN communication unit 7. Further, the server-side communication unit 32 distributes map data to the navigation device 2 via the mobile phone line when the mobile phone line communication unit 10 accesses the mobile phone line. It has become. The map data distributed in this way is received by the mobile phone line communication unit 10.

  As shown in FIG. 1, a server-side map storage unit 333 is connected to the server-side CPU 31. The server-side map storage unit 33 stores detailed and latest map data over a wide area. The navigation device 2 is configured to distribute map data in a partial range (area) of the map data in the server-side map storage unit 33. As to which range of map data should be distributed, the server-side CPU 31 sends information on the destination transmitted from the navigation device 2 side, information on the current position, storage capacity information of the navigation-side map storage unit 11 as necessary, and It is determined according to the searched reference optimum route. The server-side map storage unit 33 may store map data for a plurality of adjacent countries. The server-side map storage unit 33 may be realized by a hard disk.

  Further, as shown in FIG. 1, a server-side main storage unit 34 is connected to the server-side CPU 31. The server-side main storage unit 34 is used for storing an execution program of the server-side CPU 31, temporarily storing processing results of the server-side CPU 31, and the like. The server-side main storage unit 34 may be realized by a ROM, a RAM, or the like.

  According to the above configuration, the acquisition of new map data from the server 3 via the access point 8 and the route to the new access point 8 included in the acquired new map data are repeated while heading to the destination. Therefore, economical map data acquisition via the access point 8 can be efficiently performed in consideration of the storage capacity of the navigation-side map storage unit 11.

  As a more preferred embodiment, when the destination is set by the destination setting unit 23, the communication control unit 25 can communicate with the server 3 by both the wireless LAN communication unit 7 and the mobile phone line communication unit 10. First, the wireless LAN communication unit 7 is used for acquiring map data.

  If comprised in this way, since initial map data can be acquired via the access point 8, acquisition of map data can be performed more economically.

  More preferably, in addition to the above-described configuration, the route guiding unit 24 further includes a current one of the plurality of access points 8 when the map data acquired by the communication control unit 25 includes the plurality of access points 8. The route guidance from the position to the access point 8 existing at the farthest position on the front side in the traveling direction along the reference optimum route is performed.

  And if comprised in this way, the map data which reaches the area | region which is as close to the destination as possible in the access point 8 can be acquired in consideration of the memory capacity of the navigation side map memory | storage part 11, map data Communication frequency can be further reduced.

  Here, FIG. 3 schematically shows an example of the operation of the navigation system 1 in the present embodiment.

As shown in FIG. 3, in the present embodiment, the communication control unit 25 communicates with the server 3 via the access point 8 by using the wireless LAN communication unit 7 at the departure place such as home. The initial map data D ₁ around the reference optimal route R can be downloaded from the server 3. Since the initial map data D ₁ has a data size within the storage capacity of the navigation side map storage unit 11, it can be appropriately stored in the navigation side map storage unit 11.

Next, based on the original map data D ₁ stored in the navigation side map storage unit 11 in this way, the access point search unit 27 performs “Wi-Fi as an access point 8 as shown in FIG. Assume that “spot 1” is detected.

  In this case, the route search unit 29 searches for the optimum route from the departure place to “Wi-Fi spot 1”. Then, the route guidance unit 24 performs route guidance according to the optimum route to “Wi-Fi spot 1”.

Next, when the vehicle reaches “Wi-Fi spot 1” while receiving the route guidance, the communication control unit 25 uses the wireless LAN communication unit 7 to connect the server 3 via the “Wi-Fi spot 1”. communication with is performed by the communication, the reference optimum route new map data D ₂ around the R can be downloaded from the server 3. This new map data D ₂ also, since the data size within the storage capacity of the navigation device side map storage unit 11, which can be appropriately stored in the navigation device side map storage unit 11. Moreover, the new map data D ₂ is overwritten on the navigation device side map storage unit 11 (initial map data D ₁ is erased) for sufficient data within the storage capacity of the navigation device side map storage unit 11 it can be properly stored map data D ₂ of the size (memory capacity and almost the same size).

Next, based on the new map data D ₂ stored in the navigation-side map storage unit 11 in this way, the access point search unit 27 performs “Wi” as a new access point 8 as shown in FIG. Suppose that “-Fi spot 2” is detected.

  In this case, the route search unit 29 searches for the optimum route from “Wi-Fi spot 1” to “Wi-Fi spot 2”. Then, the route guidance unit 24 performs route guidance according to the optimum route to “Wi-Fi spot 2”.

Next, when the vehicle reaches the “Wi-Fi spot 2” while receiving the route guidance, the communication control unit 25 uses the wireless LAN communication unit 7 to connect the server 3 via the “Wi-Fi spot 2”. communication with is performed by the communication, the reference optimum route new map data D ₃ around the R can be downloaded from the server 3. This new map data D ₃ also, since the data size within the storage capacity of the navigation device side map storage unit 11, which can be appropriately stored in the navigation device side map storage unit 11 (overwritten).

At this time, since the new map data D ₃ stored in the navigation-side map storage unit 11 includes the destination, the access point search unit 27 does not search for the new access point 8. The route search unit 29 searches for an optimum route from “Wi-Fi spot 2” to the destination. Then, the route guidance unit 24 performs route guidance according to the optimum route to the destination.

  In this way, according to the configuration of the present embodiment, it is possible to go to the destination while repeatedly downloading the map data within the storage capacity of the navigation-side map storage unit 11 via the Wi-Fi spot. Occurrence can be effectively avoided.

(Embodiment of navigation method)
Next, an embodiment of a navigation method according to the present invention to which the above-described navigation device 2 is applied will be described with reference to FIG.

  In the present embodiment, first, the destination is set by the destination setting unit 23 in Step 1 (ST1) of FIG.

  Next, in step 2 (ST2), the communication control unit 25 causes the server 3 to transmit the destination map information, the storage capacity information of the navigation-side map storage unit 11 and the current position information to the server 3. Make a request. This request is made using the wireless LAN communication unit 7 as much as possible.

  Next, in step 3 (ST3), the server-side CPU 31 stores the map stored in the server-side map storage unit 33 based on the destination and current position information acquired from the navigation device 2 side in step 2 (ST2). The reference optimal route is searched using data.

  Next, in step 4 (ST4), the server-side CPU 31 distributes to the navigation device 2 based on the acquired information from the navigation device 2 side in step 2 (ST2) and the reference optimum route calculated in step 3 (ST3). Determine the initial map data to be used. The initial map data has a data size within the storage capacity of the navigation-side map storage unit 11 and is map data corresponding to the area ahead of the current direction along the reference optimum route in the traveling direction. As a premise, further optimization (specification) may be attempted. For example, the initial map data may be map data corresponding to a region that spreads by an equal distance in the lateral direction with respect to the traveling direction of the reference optimum route. The same applies to new map data.

  Next, in step 5 (ST5), the server-side CPU 31 distributes (responds) the original map data determined in step 4 (ST4) to the navigation device 2 via the server-side communication unit 32.

  Next, in step 6 (ST6), the communication control unit 25 downloads the original map data distributed in step 5 (ST5) and stores it in the navigation-side map storage unit 11.

  Next, in step 7 (ST7), the access point search unit 27 searches for the access point 8 based on the original map data stored in the navigation-side map storage unit 11 in step 6 (ST6). For convenience, it is assumed that the initial map data does not include the destination.

  Next, in step 8 (ST8), the route searching unit 29 searches for the optimum route to the access point 8 detected in step 7 (ST7).

  Next, in step 9 (ST9), the route guidance unit 24 performs route guidance to the access point 8 according to the optimum route searched in step 8 (ST8).

  Next, in step 10 (ST10), the communication control unit 25 detects the arrival of the host vehicle at the access point 8.

  Next, in step 11 (ST11), the communication control unit 25 communicates with the server 3 via the access point 8 by using the wireless LAN communication unit 7, so that the current position of the server 3 is determined. Request new map data with information transmission.

  Next, in step 12 (ST12), the server-side CPU 31 determines new map data to be distributed to the navigation device 2 based on the acquired information from the navigation device 2 side in step 11 (ST11).

  Next, in step 13 (ST13), the server-side CPU 31 distributes (responds) the new map data determined in step 12 (ST12) to the navigation device 2 via the server-side communication unit 32.

  Next, in step 14 (ST14), the communication control unit 25 downloads the new map data distributed in step 13 (ST13) via the wireless LAN communication unit 7 and stores it in the navigation side map storage unit 11 ( (Overwrite).

  Next, in step 15 (ST15), the navigation CPU 5 determines whether or not the new map data stored in the navigation-side map storage unit 11 in step 14 (ST14) includes the destination. If a positive determination result is obtained in step 15 (ST15), the process proceeds to step 16 (ST16). If a negative determination result is obtained, the process returns to step 7 (ST7).

  Here, when the process proceeds to step 16 (ST16), the route search unit 29 searches for the optimum route from the access point 8 to the destination, and the route guidance unit 24 uses the optimum route according to the optimum route. Route guidance to the ground.

  On the other hand, when returning to step 7 (ST7), the processing after step 7 (ST7) is repeated for new map data.

  In addition, this invention is not limited to embodiment mentioned above, A various change can be made in the limit which does not impair the characteristic of this invention.

  For example, by providing a configuration corresponding to the above-described access point search unit 27 and route search unit 29 on the server 3 side, the search for the access point 8 based on the map data to be distributed to the navigation device 2 and the detected access The search for the optimum route to the point 8 or the destination may be performed on the server 3 side. In this case, the information on the optimum route to the access point 8 / destination may be distributed in accordance with the distribution of the map data.

  If comprised in this way, the processing burden by the side of the navigation apparatus 2 can be eased.

2 navigation device 3 server 7 wireless LAN communication unit 10 mobile phone line communication unit 11 navigation side map storage unit 22 current position calculation unit 23 destination setting unit 24 route guidance unit 25 communication control unit

Claims (10)

Current position detecting means for detecting the current position;
Destination setting means for setting the destination;
First communication means for acquiring map information from the server by first communication with the server via an access point;
Second communication means for acquiring map information from the server by second communication with the server via a mobile phone line;
Storage means for storing the map information acquired by the first communication means or the second communication means;
A navigation device comprising: route guidance means for performing route guidance to the destination set by the destination setting means based on the map information stored in the storage means;
When the destination is set by the destination setting means, the searched reference optimum route to the destination, the current position detected by the current position detecting means, and storage capacity information of the storage means One of the first communication means and the second communication means capable of communicating with the server, on the front side in the traveling direction along the reference optimum path with respect to the current position. Communication control means for acquiring, from the server, map information corresponding to the area of the map information having an information amount within the storage capacity of the storage means,
The route guidance means performs route guidance to the access point included in the map information based on the map information acquired from the server by the communication control means,
The communication control means triggers the first communication means via the access point when the current position has reached the access point by route guidance to the access point by the route guidance means. 1, the map information corresponding to the area ahead of the access point along the reference optimum route with respect to the access point and having the information amount within the storage capacity of the storage means Let's get from
The acquisition of the new map information via the access point by the communication control means and the route guidance to the new access point included in the new map information by the route guidance means Until the destination is included in the correct map information, and when the destination is included in the new map information, the route guidance means A navigation device characterized by performing route guidance to the destination. The communication control means, when the destination is set by the destination setting means, when both the first communication means and the second communication means can communicate with the server, The navigation device according to claim 1, wherein one communication unit is used to acquire the map information. When the map information acquired by the communication control unit includes a plurality of the access points, the route guidance unit proceeds along the reference optimal route from the current position among the plurality of access points. The navigation device according to claim 1 or 2, wherein route guidance to the access point existing at the farthest position on the front side in the direction is performed. The reference optimum route is searched on the navigation device body side or the server side where the current position and the destination information are acquired from the navigation device body,
The navigation device body includes:
An access point search means for searching for the access point included in the map information when the destination is not included in the map information acquired by the communication control means;
A waypoint setting means for automatically setting the access point detected by the access point search means as a waypoint to be routed to the destination;
A route searching means for searching for an optimum route to the access point set as a waypoint by the waypoint setting means based on the map information acquired by the communication control means, and
The navigation according to any one of claims 1 to 3, wherein the route guidance unit performs route guidance to the access point in accordance with the optimum route searched by the route search unit. apparatus. The reference optimum route is searched on the navigation device body side or the server side where the current position and the destination information are acquired from the navigation device body,
When the destination is not included in the map information to be acquired by the navigation device body, the server searches for the access point included in the map information, and detects the detected access point to the destination. Automatically set to the waypoint to be routed to, and search for the optimum route to the access point set to this route point based on the map information to be acquired by the navigation device body,
The navigation device according to any one of claims 1 to 3, wherein the route guidance unit performs route guidance to the access point according to the optimum route searched by the server. The map information acquired from the server by the first communication with the server via the access point or the second communication with the server via the mobile phone line is stored in the storage means of the navigation device, and stored in this storage means A navigation method for guiding a route to a set destination based on the map information,
When a destination is set by the navigation device, a first step of searching for a reference optimum route to the destination;
Execution of the first communication and the second communication based on the reference optimum route searched in the first step, the current position of the navigation device, and the storage capacity information of the storage means The map information corresponding to the area on the front side in the traveling direction along the reference optimum route with respect to the current position, and map information having an amount of information within the storage capacity of the storage means is obtained from the server. A second step of delivering to the navigation device;
On the basis of the map information distributed in the second step, the navigation device side performs route guidance to the access point included in the map information;
When the current position has reached the access point by route guidance to the access point in the third step, the reference optimum route for the access point is obtained by the first communication via the access point. 4th step of delivering new map information corresponding to the area ahead in the traveling direction along the line and having an information amount within the storage capacity of the storage means from the server to the navigation device; ,
Distribution of the new map information through such an access point and route guidance to the new access point included in the new map information are included in the new map information. A fifth step that is repeated until
A sixth step of guiding a route to the destination based on the new map information on the navigation device side when the new map information includes the destination. A navigation method characterized by the above. The second step uses the first communication for distribution of the map information when both the first communication and the second communication can be executed when the destination is set. The navigation method according to claim 6, wherein the navigation method includes: In the third step and the fifth step, when the map information distributed from the server includes a plurality of the access points, the reference optimal route from the current position among the plurality of access points. The navigation method according to claim 6, wherein a route guidance to the access point existing at the farthest position on the front side in the traveling direction along the line is performed. The first step is a step performed on the navigation device side or on the server side where the current position and the destination information are acquired from the navigation device;
A seventh step of searching the access point included in the map information on the navigation device side when the destination is not included in the map information distributed in the second step or the fourth step. When,
An eighth step of automatically setting the access point detected in the seventh step as a waypoint to be routed to the destination on the navigation device side;
In the eighth step, the navigation device searches for the optimum route to the access point set as a waypoint on the basis of the map information distributed in the second step or the fourth step. Including 9 steps and
The third step and the fifth step are steps for guiding a route to the access point according to the optimum route searched in the ninth step. Item 9. The navigation method according to any one of Items8. The first step is a step performed on the navigation device side or on the server side where the current position and the destination information are acquired from the navigation device;
7 ′ step of searching for the access point included in the map information on the server side when the destination is not included in the map information to be distributed in the second step or the fourth step When,
An 8 ′ step of automatically setting the access point detected in the 7 ′ step as a waypoint on the server side to be routed to the destination;
The server side searches for an optimum route to the access point set as a transit point in the eighth step based on the map information to be distributed in the second step or the fourth step. 9 'step and
The third step and the fifth step are steps for guiding a route to the access point according to the optimum route searched in the ninth 'step. The navigation method according to claim 8.