JP2020027083A - Navigation device and program - Google Patents

Abstract

To provide a navigation device with which it is possible to search for an appropriate route using the network data acquired from an information processing device via a network.SOLUTION: The present invention provides a navigation device 35 comprising: communication determination means 52 for determining whether or not communication with an information processing device is possible; map data acquisition means 45 for acquiring first map data held by the information processing device; first map data storage means 55 for storing the first map data acquired by the map data acquisition means; second map data storage means 56 for previously storing second map data; base point setting means 54 which, when it is determined by the communication determination means that communication with the information processing device is impossible, sets a base point to the boundary of the first map data stored in the first map data storage means and the second map data; and display processing means 57 for displaying a route searched using the base point as a waypoint.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a navigation device and a program.

  A navigation device mounted on a vehicle or the like can perform a route search or draw an electronic map by using preinstalled map data so that navigation can be performed by itself. In recent years, since the cost of wireless communication has dropped, a communication device may be mounted on a vehicle, and a vehicle called a connected car that provides various services to users such as occupants by communication has begun to spread. . Although there is no clear definition of a connected car, it may refer to something that can be connected to a network such as the Internet, or a vehicle may use information transmitted from or received from the vehicle. Sometimes it refers to something.

  Although the map data includes roads and various POIs (Point Of Interest), new roads are being constructed and POIs are constantly being abolished. It will be old. Therefore, a navigation device that can update map data using wireless communication is known (for example, see Patent Document 1). In Patent Literature 1, a server manages a date and time when link data is updated for each link and a range affected by the update, and the server determines a link in an area designated by the terminal and a link affected by the update of the link by the terminal. Is disclosed. Updating a part of the preinstalled map data in this way is called differential update. In the differential update, only the changed map data is transmitted, so that the communication load is reduced and the user can use the latest map data. In addition, wireless distribution of map data can be easily applied to a connected car.

  However, if the differential update is performed, road network data having different versions will be mixed. If there is a portion having inconsistency in road network data of different versions, it becomes difficult to search for a route that crosses one version of road network data and another version of road network data.

  To cope with such inconvenience, a technology has been devised that enables a route search even when road network data of different versions coexist (for example, see Patent Document 2). Patent Literature 2 discloses a route guidance apparatus that guides a base point in a guidance route in the section data that is the same as the version of the section data to which the current location or the departure point belongs, is continuous with the section data, and is closest to the section data to which the destination belongs. Is disclosed.

WO 2006/011278 JP 2017-133976 A

  However, in the differential update, there is a problem that an appropriate route cannot be searched unless road network data of different versions is matched.

  The present invention has been made in view of the above circumstances, and has as its object to provide a navigation device that can search for an appropriate route using network data acquired from an information processing device via a network.

  In view of the above problem, the present invention is a navigation device that can communicate with an information processing device via a network to acquire first map data, and determines whether communication with the information processing device is possible. Communication judging means for judging, map data obtaining means for obtaining the first map data held by the information processing apparatus, and first map storing the first map data obtained by the map data obtaining means A data storage unit, a second map data storage unit that stores second map data in advance, and the first map data storage unit when the communication determination unit determines that communication with the information processing apparatus is not possible. Base point setting means for setting a base point at a boundary between the first map data and the second map data stored in the means, and a display for displaying a route searched using the base point as a transit point Characterized in that it has a physical means.

  A navigation device capable of searching for an appropriate route using network data acquired from an information processing device via a network can be provided.

It is an example of a figure explaining operation of a navigation device at the time of off-line. 1 is an example of a system configuration diagram of a navigation system according to the present embodiment. It is an example of a figure explaining the kind of navigation device. FIG. 2 is an example of a hardware configuration diagram of a server and a navigation device. FIG. 2 is an example of a functional block diagram for explaining functions of a server and a navigation device included in the navigation system in a block shape. It is an example of a figure explaining operation of a navigation device at the time of online and offline at the time of a route search. It is an example of the flowchart figure which shows operation | movement of the navigation apparatus when a user searches for a route. FIG. 8 is a diagram illustrating an example of determining whether or not there is the latest map data on a route searched using pre-in map data. It is a figure which shows an example of the path | route (link) corresponding to the route and the route in the boundary of the latest map data and the pre-in map data. FIG. 11 is an example of a flowchart showing a procedure for searching for a route using the latest map data when the latest map data can be used offline. It is a figure showing the example of a display of the course in the electronic map displayed by a display. It is an example of a figure explaining search by only the latest map data. It is a flowchart figure of the procedure which the route search part determines whether route search can be performed by the latest map data. FIG. 13 is an example of a diagram illustrating a route search performed by a navigation device (third embodiment). It is a figure showing the road which passes the boundary of the latest map data and the pre-in map data. It is an example of a figure explaining the determination method of base points A-D. FIG. 3 is an example of a flowchart illustrating the operation of the navigation device according to the embodiment. It is a figure showing an example of a selection screen of a search mode.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

<Outline of operation of navigation device of this embodiment>
First, an outline of the operation of the navigation device of the present embodiment will be described with reference to FIG. FIG. 1 is an example of a diagram for explaining the operation of the navigation device 35 when offline. The navigation device 35 is pre-installed with map data covering the whole country. Hereinafter, this map data is referred to as pre-in map data 8 (second map data).

  It is assumed that the navigation device 35 in FIG. 1 is mounted on a so-called connected car, and can communicate with the server 31 wirelessly. The map data of the server 31 is appropriately updated to the latest map data. Hereinafter, this map data is referred to as latest map data 7 (first map data). When online, the navigation device 35 can acquire the latest map data 7 from the server 31 in mesh units.

  As shown in FIG. 1A, when performing a route search while offline, the navigation device 35 performs a route search using the pre-in map data 8. However, since the navigation device 35 of the present embodiment holds (caches) the latest map data 7 acquired from the server when online, the latest situation is possible if a route search using the latest map data 7 is possible. Can be provided.

  Therefore, the navigation device 35 of the present embodiment determines whether or not the latest map data 7 exists on the route 6 searched with the pre-in map data 8 when offline, and uses the latest map data 7 when it exists. Perform a route search.

  FIG. 1B shows the latest map data 7 acquired from the server 31 in units of meshes, superimposed on the route 6. Therefore, in the range where the route 6 and the latest map data 7 overlap, a route search can be performed using the latest map data 7. In a range where the route 6 and the latest map data 7 do not overlap, the pre-in map data 8 is used.

  As described above, in the present embodiment, a route search is performed for each of the latest map data 7 and the pre-in map data 8 (FIG. 1C). Let S be the original departure point and G be the original destination. A base point A is set in both map data, and from the starting point S to the base point A on the latest map data 7 side, the route 5 searched with the latest map data 7 is used, and from the base point A on the pre-in map data 8 side to the destination G Until the above, the route 6 searched in the pre-in map data 8 is used. When the coordinate position of the current position reaches the base point A on the latest map data 7, the latest map data 7 is switched to the pre-in map data 8.

  The switching timing of the map may be the timing of reaching the base point, or may be determined by determining whether or not the display area of the map is covered by one of the maps. When switching between the latest map data 7 and the pre-in map data 8, an announcement "the map will be switched" may be made. Note that the base point is not limited to a node.

  In this case, the route from the starting point S to the base point A can be searched with the latest map data 7. Since the route search of the pre-in map data 8 has been completed, the search is unnecessary, but may be performed again. A route from the departure point S to the destination G is connected to a route from the departure point S to the base point A (a link of the latest map data 7 as described later) and a route from the base point A to the destination G.

  When the base point A is determined, in order to cope with a case where the mesh boundary between the latest map data 7 and the pre-in map data 8 is inconsistent, for example, the coordinates of the route of the mesh boundary between the latest map data 7 and the pre-in map data 8 are calculated. It is determined whether there is a road within a predetermined distance and having the same road attribute.

  In this way, the latest map data 7 obtained from the server can be effectively used within a usable range, even when offline. As a user, even a part of the route can travel on the route searched by the latest map data 7, and it is expected that the traveling time is shortened.

<About terms>
Offline includes a state where complete communication is not possible and a case where it takes a certain time or more to receive the latest map data 7. For example, the case where the communication band is less than the threshold may be referred to as offline.

  In the present embodiment, as will be described later, a “always” pre-in map is drawn in area 2 of the drawing area (an area in which the pre-in map data is drawn). The drawing area corresponds to a drawing memory such as a VRAM (Video RAM). The navigation device switches between area 1 and area 2 for display, and displays area 1 with priority over area 2.

  Even if it is referred to as “always”, a state in which the image is not drawn temporarily may occur, such as at the moment when the display range of the display device 213 is switched by the movement of the vehicle or the scroll operation of the user. In addition, when the drawing of area 1 (the area where the latest map data is drawn) of the drawing area is prioritized and the drawing of area 2 is later in time, the pre-in map is drawn in area 2 and the time required for drawing of area 1 May not occur. As described above, “always” includes a situation where drawing is not performed to the extent that the user feels that there is no delay when switching from area 1 to area 2.

<System configuration example>
FIG. 2 is an example of a system configuration diagram of the navigation system 100 according to the present embodiment. The navigation system 100 has a server 31 and a navigation device 35 communicably connected via a network 34.

  The network 34 is constructed by mainly wireless lines (3G, 4G, LTE, wireless LAN, WiMAX, etc.) such as a mobile phone network provided by a line carrier, and a provider network of a provider connecting various lines to the Internet. Have been. Since the server 31 is located in a facility such as a data center, the server 31 may include an indoor LAN, a wide area Ethernet (registered trademark), or the like. It also includes the so-called Internet. The network 34 may be constructed by wire or wireless, and may be a combination of wire and wireless.

  A base station 32 such as an access point is connected to the network 34, and the navigation device 35 connects to the network 34 by connecting to the base station 32 wirelessly. The navigation device 35 communicates with the base station 32 via a wirelessly constructed communication network.

  The server 31 provides the navigation device 35 with navigation services and functions. For example, the position information of the current position is acquired from the navigation device 35, and the latest map data 7 around the current position is transmitted to the navigation device 35. When the route search request is acquired together with the position information of the departure place and the destination, the route is searched and the route information and the guide information are transmitted to the navigation device 35.

  A navigation device 35 can be connected to the network 34. Connection refers to the above-mentioned online state. The number of navigation devices 35 that communicate with the server 31 is not limited to one, and a plurality of navigation devices 35 can be provided with services and functions from the server 31.

  The navigation device 35 is used by being mounted on the moving body 9. 2 is a vehicle that runs using at least one of an internal combustion engine and an electric motor as power. Vehicles include motorcycles as well as four-wheeled vehicles. In recent years, a mobility (commuter) of one or two persons has been marketed as a vehicle. Ships may be included. In addition, a bicycle (including electric assist), a light vehicle, and the like that have no power are also the moving objects 9. Further, this does not mean that the navigation device 35 of the present embodiment cannot be used for a pedestrian. A pedestrian can also move with the navigation device 35 carried.

  The navigation device 35 has a navigation function by itself (even without the server 31). That is, the route from the departure point to the destination is searched and set as a road map, and the route and the current location are displayed on an electronic map displayed on a display device 213 such as a display or a HUD (Head Up Display), or the route is displayed. Based on the route change, an appropriate route is guided by voice guidance or an animation on an electronic map before the route change. When mounted on a vehicle, it may be called a “car navigation device”. As described below, there is not only a dedicated navigation device 35 mounted on a vehicle but also a general-purpose navigation device 35 in which a smartphone, a tablet, or the like executes an application to perform navigation.

  FIG. 3 is an example of a diagram for explaining types of the navigation device 35. The navigation device 35 may be a dedicated terminal 352 or a general-purpose information processing terminal 351. The navigation device 35 as the dedicated terminal 352 may have an AV (Audio Visual) function. The AV function is a function of reproducing content broadcast on a radio / television or content stored in a storage medium such as a DVD, and displaying surrounding images captured by a camera. Further, a function for displaying a Web page on the Internet by connecting to the network 34 may be provided. The navigation function and the AV function may be collectively referred to as an AVN function.

  The navigation device 35 as the general-purpose information processing terminal 351 is, for example, a smartphone, a tablet terminal, a mobile phone, a PDA (Personal Digital Assistant), a notebook PC, a wearable PC (for example, a wristwatch type, a sunglass type, and the like). is there. The general-purpose navigation device 35 is not limited to these devices, and may be any device that is appropriate for displaying a navigation screen and providing route guidance. These general-purpose information processing terminals 351 are usually used as general-purpose information processing devices. However, when application software for navigation is executed, route search, route guidance, and the like are performed similarly to the dedicated terminal 352.

  The application software executed by the general-purpose information processing terminal 351 may be either application software dedicated to navigation or a Web browser.

  Further, the navigation device 35 may be capable of switching between a state of being mounted on the moving body 9 and a state of being portable in both the general-purpose information processing terminal 351 and the dedicated terminal 352.

<Hardware configuration>
FIG. 4 is an example of a hardware configuration diagram of the server 31 and the navigation device 35. The server 31 and the navigation device 35 have the function of an information processing device. As shown in FIG. 4A, the server 31 includes, as hardware configurations, a CPU (Central Processing Unit) 211, a ROM (Read Only Memory) 215, a RAM (Random Access Memory) 216, an auxiliary storage device 217, and It has a communication device 214.

  As shown in FIG. 4B, the navigation device 35 has a hardware configuration of a CPU 211, a ROM 215, a RAM 216, an auxiliary storage device 217, an input device 212, a display device 213, a communication device 214, and a voice input / output device 218. , And a GPS receiver 219.

  The CPU 211 executes various programs and performs arithmetic processing. The ROM 215 stores programs and the like necessary at the time of startup. The RAM 216 is a work area for temporarily storing processing in the CPU 211 and for storing data. The auxiliary storage device 217 is a nonvolatile memory for storing various data and programs 2101, 2102.

  The input device 212 of the navigation device 35 can be realized by a touch panel capable of detecting a contact position (touch coordinates) on the screen instead of or in addition to the keyboard and the mouse. Further, the input device 212 may have a function as a voice recognition device that recognizes voice input by the voice input / output device 218.

  The display device 213 is a display, a projector, or a HUD, and displays, for example, a navigation screen or the like. The communication device 214 connects to the network 34 via the base station 32 and performs communication with the server 31 and the like. The voice input / output device 218 is a device for inputting / outputting voice, and outputs voice guidance for navigation, for example. The GPS receiver 219 is an example of a GNSS (Global Navigation Satellite System) that receives a radio wave from a GPS satellite and calculates the current location.

  The programs 2101 and 2102 stored in the server 31 or the auxiliary storage device 217 of the navigation device 35 are distributed while being stored in a storage medium such as a USB memory. Alternatively, the program is distributed by the navigation device 35 downloading the program from a distribution server that distributes the program. The program 2102 of the navigation device 35 may be application software dedicated to route guidance or browser software. Further, the program may be distributed in an executable format or an installation format.

  It should be noted that cloud computing may be applied to the server 31. Cloud computing refers to a usage mode in which resources on a network are used without being conscious of specific hardware resources. Therefore, the illustrated hardware configuration of the server 31 does not need to be housed in one housing or provided as a unit, and indicates hardware elements that the server 31 preferably has. . It should be noted that the server 31 may be provided by a single information processing apparatus instead of cloud computing.

<Functional configuration example>
Next, the function of the navigation system 100 will be described with reference to FIG. FIG. 5 is an example of a functional block diagram illustrating the functions of the server 31 and the navigation device 35 of the navigation system 100 in a block form.
<< About the server >>
The server 31 includes a second receiving unit 11, a route searching unit 12, a route information generating unit 13, a guide information generating unit 14, a map data providing unit 15, and a second transmitting unit 16. These functions are functions or means realized by the CPU 211 shown in FIG. 4A executing the program 2101 and cooperating with the hardware of the server 31. Some or all of these functions may be realized by a hardware circuit such as an IC.

  In addition, the server 31 includes the storage unit 20 configured by the auxiliary storage device 217, the ROM 215, or the RAM 216 illustrated in FIG. In the storage unit 20, a map drawing DB 17, a road network DB 18, and a facility information DB 19 are constructed. Each of these DBs may not be directly owned by the server 31 and may be located at any location on the network 34 to which the server 31 can access.

  First, each database will be described.

Table 1 schematically shows map drawing data stored in the map drawing DB 17. The map drawing DB 17 stores map drawing data for the navigation device 35 to draw an electronic map of the latest map data 7. The information displayed on the electronic map has many display objects such as prefectural divisions, green areas and rivers, roads and railroads, signs and notes, so they are classified into similar characteristics and classified according to the display target of each classification. You can draw on. Each of the classified display objects or a state in which the display objects are drawn is called a layer, and the electronic map is drawn by overlapping several layers. The map data of each layer is described in a format suitable for a display target out of vector data or raster data. The data file of Table 1 includes data of each layer.

  As shown in Table 1, the map drawing data is divided into meshes for each region such as longitude and latitude, and one or more meshes are combined to create a one-screen electronic map. In the case of vector data, the positions of points, polylines, and polygons are determined by latitude and longitude. In the case of raster data, data corresponding to the scale is prepared in association with the latitude and longitude. Communication load can be reduced by using the latest map data 7 as vector data. The update information holds, for each mesh, when the latest map data 7 was last updated.

  As described above, the map drawing data in the map drawing DB 17 is divided into meshes and associated with the mesh IDs. When the drawing map data and the road network data of the latest map data 7 are transmitted to the navigation device 35, Sent for each mesh.

Table 2 schematically shows the configuration of the road network DB 18. The road network DB 18 is road network data representing the structure of a road on which vehicles can pass among the latest map data 7, and the node table in Table 2 (a) and the link table in Table 2 (b) are mutually referred to. It is held in a possible structure. In the node table, a node ID for identifying the node, coordinates (latitude / longitude) of the node, and update information are registered. A node is a node on the road network representation. Specifically, the node is, for example, an intersection, a junction, a junction, a bend, or the like. If the node ID is known, the link connected to the node can be found from the link table, so that the route can be searched by referring to the node table and the link table mutually. The update information indicates when the node was last updated.

  In the link table, a link ID for identifying the link, a link start node, a link end node, a link length, a width, a road type, a section ID, a regulation such as a speed limit, a mesh ID, and update information are provided. Is registered. The link represents a road connecting the nodes, and the link is a line connecting the nodes. The road type refers to a type of road, such as a national road, a general road, a prefectural road, an expressway, a motorway, a tunnel, and a private road. A section is a unit for handling a certain number of links at once. One section is determined, for example, as follows. It is determined according to a predetermined rule such as two links or three links. In addition, nodes and links for approximately several hundred meters may be formed as one section. In addition, sections may be set so that sections are switched according to road types, sections such as streets, addresses, and issues. The regulations register the traffic rules that vehicles must observe. Update information is the same as in the node table.

  Although the details of the facility information DB 19 are omitted, the facility information DB 19 registers business names, store names, addresses, postal codes, telephone numbers, facility coordinates, icons, and the like in association with each other.

(About the functions of the server)
Next, functions of the server 31 will be described. The second receiving unit 11 receives various requests related to navigation from the navigation device 35. This request includes, for example, position information such as a current position, a destination, or an arbitrary position for requesting the latest map data 7 (map data for drawing and road network data). There is also a case of a route search request designating a departure place and a destination. In addition, a request to provide various functions of the server 31 is received. The second receiving unit 11 distributes these requests to the route search unit 12 and the map data providing unit 15.

  The route search unit 12 searches for a route from the departure place to the destination included in the route search request. When the destination is given by a facility name, an address, or the like, the facility information DB 19 is searched to acquire facility coordinates that are the position of the destination. In response to the route search request, the route search unit 12 uses the road network DB 18 in which the road network data of the latest map data 7 is stored to search for a route between the departure point and the destination, and creates a search result. The search result is a list in which links or nodes on which the vehicle travels are set in order. For the route search, the Dijkstra method and the A-Star method are known in which the link length, width, and congestion are converted into costs, and the route that minimizes the total cost from the departure point to the destination is selected. . The search result is sent to the route information generator 13.

  The route information generator 13 generates route information. The route information according to the present embodiment is a coordinate point sequence in which a link included in the search result is represented by coordinates. That is, each link is converted into latitude and longitude coordinates at regular intervals, and a coordinate point sequence in which the coordinates from the starting point to the destination are arranged in the moving order is used as the path information.

  The guidance information generation unit 14 generates guidance information for guiding the user based on the search result of the route. The guidance information is guidance points and information for moving the user along the route at each guidance point. The guidance information generation unit 14 calculates an angle between links and specifies a node whose course is changed at an angle equal to or larger than a threshold. A guide point (position) is a predetermined distance (for example, several km, several hundred meters, several tens meters, immediately before, etc.) of this node. In many cases, a plurality of guidances according to the distance to the node are provided for one course change opportunity. If the guidance point is a right or left turn, a voice message (voice data or text data) such as "turn right at a meter distance." At a large intersection, a 3D display animation is prepared, and in the guidance information, an animation or the like is associated with the guidance point. Note that the guide point may be set at a passing node (straight-ahead node) for preventing a non-guide section from becoming long. The navigation device 35 guides the route by voice or video using the guide points. The guidance information is sent to the map data providing unit 15.

  The map data providing unit 15 obtains the latest map data 7 around the position from the map drawing DB 17 and the road network DB 18 for the drawing map data of the latest map data 7 and the position information for requesting the road network data. I do. Further, for the route information (or any of the search results), the map data for drawing and the road network data of the latest map data 7 of all meshes through which the route passes (including the link of the route information) are mapped. It is acquired from the drawing DB 17 and the road network DB 18. The latest map data 7 may be transmitted together with the route information, or may be transmitted from the navigation device 35 upon request.

  The second transmission unit 16 transmits the latest map data 7 (map data for drawing and road network data), route information, and guidance information to the navigation device 35. Since the navigation device 35 draws the electronic map using the map data for drawing of the latest map data 7 and the route information, the navigation device 35 draws the map data for drawing, the route information, and the guidance information of the latest map data 7. It is in the form of program code and data to be executed. On the other hand, when the map data for drawing of the latest map data 7 is provided as raster data, image data such as GIF, BMP, and JPEG and program codes (route information and guidance information) are transmitted. When the navigation device 35 executes a browser application, JavaScript (registered trademark) is known as a program code.

<< About the navigation device >>
Subsequently, functions or means of the navigation device 35 will be described. The navigation device 35 includes a first transmission unit 41, an information requesting unit 42, a position detection unit 43, an operation reception unit 44, a latest map data management unit 45, a first reception unit 46, a route guidance unit 47, a navigation screen drawing unit 48, It has a drawing area 49, a route search unit 51, a communication determination unit 52, a base point setting unit 54, and a display processing unit 57. These are functions or means realized by the CPU 211 shown in FIG. 4B executing the program 2102 and cooperating with the hardware of the navigation device 35. Some or all of these functions may be realized by a hardware circuit such as an IC.

  Further, the navigation device 35 has a storage unit 60 constructed by the auxiliary storage device 217, the ROM 215, or the RAM 216 shown in FIG. The storage unit 60 includes a latest map data storage unit 55 and a pre-in map data storage unit 56. The latest map data storage unit 55 stores (caches) the latest map data 7 (map data for drawing and road network data) transmitted from the server 31. Which mesh of the latest map data 7 (map data for drawing and road network data) is stored depends on which mesh has been displayed on the display device 213 by the user in the past, or which mesh has been searched. It depends on whether it passes through or not. However, not all the meshes passing through the route are stored in the latest map data storage unit 55. This is because the navigation device 35 may not have received the latest map data 7 (drawing map data and road network data) if a search has been made to the destination but the vehicle has not actually moved along the route. is there.

  The pre-in map data storage section 56 stores pre-in map data 8. The pre-in map data 8 is map data covering the whole of Japan. For example, if the place where the moving body 9 is likely to move is preferably covered even if the place where the moving body 9 rarely moves is covered. However, in Japan, it is not necessary to guarantee that there is no area without map data. The pre-in map data 8 is installed in advance when the navigation device 35 is shipped. Alternatively, it is installed at least when the user starts using it. Further, the entire pre-installed pre-in map data 8 may be updated by a dealer or the like. In this case, the installed map data is a pre-in map. Note that the structure of the pre-in map data 8 may be the same as that of the latest map data 7.

  In most cases, the version of the latest map data 7 is newer than the version of the plain map data 8, but immediately after the plain map data 8 is installed, the version of the latest map data 7 is the same as the version of the plain map data 8. In some cases.

(About the function of the navigation device)
Next, functions of the navigation device 35 will be described. The first transmission unit 41 transmits various requests such as position information and a route search request to the server 31. The first receiving unit 46 also receives the latest map data 7 (map data for drawing and road network data), route information, and guidance information from the server 31. The information request unit 42 sends various information such as position information (map request) and a route search request to the first transmission unit 41 based on requests from the position detection unit 43, the operation reception unit 44, and the navigation screen drawing unit 48. Is sent.

  The operation receiving unit 44 receives an operation for displaying an electronic map from the user, receives at least an input of a destination for a route search, and, if necessary, receives a departure point other than the current location. In addition, instructions for starting route guidance, for rerouting, for enlarging and reducing the size of the navigation screen, and for changing the display range are received.

  The position detection unit 43 detects the current location periodically, for example, using the GPS receiver 219, and in response to a user operation. The detected position information of the current position is transmitted from the first transmission unit 41 to the server 31 alone or together with the route search request. Further, the position information detected by the position detection unit 43 can use each function of the navigation device 35. For example, the route guidance unit 47 and the navigation screen drawing unit 48 may use the position information.

  The route guidance unit 47 performs route guidance based on the route information acquired from the server 31 and the current location. That is, when the current location of the moving body 9 arrives at the guide point included in the route information, the voice input / output device 218 outputs voice data indicating a turn or the like. The voice data may be transmitted from the server 31 or may be generated by the navigation device 35 performing voice synthesis based on the text data for guidance. When the current location of the moving object 9 arrives at the guide point included in the route information, the route guide unit 47 displays a 3D display of the intersection, an enlarged display of the intersection, and a signboard icon that displays a road name on the electronic map. Or superimposed on the part.

The communication determination unit 52 monitors the communication state between the navigation device 35 and the server 31 at the following timing to determine whether the navigation device 35 is online or offline.
(i) Timing at which the navigation device 35 such as IG-ON or ACC-ON starts displaying an electronic map
(ii) Timing at which the drawing range of the electronic map displayed by the display device 213 is changed
(iii) Periodic timing in the offline state, that is, whether online or offline is determined at the timing when the latest map data 7 (map data for drawing and road network data) is required. In the case of offline, since the pre-in map is displayed, it is periodically determined whether the user is online or offline to display the latest map at an early stage.

  Whether the server is online or offline is determined based on whether or not a band capable of receiving the latest map data 7 (map data for drawing and road network data) transmitted by the server 31 is secured as described above. do it. Although there are various determination methods, for example, the communication speed [bps] of a certain amount of data is measured, or the time until a response is returned to some inquiry is measured and compared with a threshold. The communication determination unit 52 notifies the display processing unit 57, the route search unit 51, and the navigation screen drawing unit 48 of online or offline.

  The latest map data management unit 45 causes the latest map data (drawing map data and road network data) received by the first reception unit 46 to be stored in the latest map data storage unit 55 of the storage unit 60. When the map drawing data of the same area as the area already stored in the latest map data storage unit 55 is transmitted, the update information may be compared and overwritten when the update information is newer. The same applies to road network data. In this way, the latest map data can always be held.

  When the route is off-line, the route search unit 51 searches the route from the departure point to the destination included in the route search request using the pre-in map data 8. However, even when the route search unit 51 is online, it is preferable to search for a route using the pre-in map data 8. As a result, a path can be provided without delay even if the path is switched from online to offline. The route information is notified to the navigation screen drawing unit 48.

  In addition, the route search unit 51 may perform a route search using the latest map data 7 when the latest map data 7 is available when offline. Although the details will be described later, the base point setting unit 54 determines that the latest map data 7 is present on the route searched by the pre-in map data 8, and further determines the route of the mesh boundary between the latest map data 7 and the pre-in map data 8. If a road having the same attribute can be found within a predetermined distance from the coordinate position (hereinafter referred to as “when the latest map data 7 can be used offline”), the route search unit 51 Route search using.

  When online, the navigation screen drawing unit 48 draws an electronic map based on the map drawing data among the latest map data 7 received from the server 31 and writes the electronic map in the area 1 of the drawing area 49. The drawing area 49 corresponds to a drawing memory, and is a memory in which an electronic map is drawn. The drawing area 49 is divided into an area 1 where the latest map data 7 is drawn and an area 2 where the pre-in map data 8 is drawn. Actually, they are classified by, for example, addresses.

  Further, the navigation screen drawing unit 48 draws a route to the destination on the electronic map based on the route information. If no route is set, no route information is received, so no route is drawn. Road network data in the latest map data 7 is used for map matching of the position of the vehicle.

  In addition, when the user displays the electronic map or starts the navigation, the navigation screen drawing unit 48 always (whether online or offline) draws the map from the pre-in map data 8 read out from the pre-in map data storage unit 56. An electronic map is drawn based on the application data and written in area 2 of the drawing area 49. In addition, the route to the destination is drawn on the electronic map based on the route information. The road network data in the pre-in map data 8 is further used for map matching of the own vehicle position.

  However, when the latest map data 7 can be used offline, the navigation screen drawing unit 48 draws the latest map data 7 and the route in the area 1 and the pre-in map data 8 in the area 2. In a state where the latest map data 7 is displayed only on a part of the display device 213, the user sees the maps of the area 1 and the area 2 in a mixed manner.

  The display processing unit 57 displays the latest map of the area 1 when the latest map of the area 1 is cached even when online or offline, and displays the area 2 when the offline map is not cached and the latest map of the area 1 is not cached. Is displayed on the display device 213. Therefore, the latest map of the area 1 is displayed online, only the pre-in map of the area 2 is displayed offline, only the map of the area 1 (when the entire range of the display device 213 is the latest map data 7), or the area 1 and the area 2 Are displayed (when the latest map data 7 is displayed only on a part of the display device 213).

  Note that the navigation screen drawing unit 48 acquires the current location in any of the areas 1 and 2, and renders the current location icon superimposed on the electronic map.

  It is assumed that the function of the route search unit 51 is the same as that of the route search unit 12. When the latest map data 7 can be used offline, the route search unit 51 may perform a route search using the latest map data 7. When the latest map data 7 cannot be used offline, the route search unit 51 uses the pre-in map data 8. Perform a route search.

<Operation procedure>
Hereinafter, operation procedures of some phases will be described.

<Process during route search>
Subsequently, a process at the time of a route search will be described. For convenience of explanation, before describing the route search method of the present embodiment, a standard route search method when the latest map data 7 can be used and when it cannot be used will be described.

  FIG. 6 is an example of a diagram for explaining the operation of the navigation device 35 at the time of online and offline in the route search. FIG. 6A shows the operation of the navigation device 35 when online, and FIG. 6B shows the operation of the navigation device 35 when offline.

  When online, the navigation device 35 acquires the map drawing data and the road network data of the latest map data 7 from the server 31, but can also acquire the route information from the server 31. If the navigation device 35 performs a route search, it is necessary to acquire map drawing data and road network data of the latest map data 7 over a wide range from the departure point to the destination from the server 31 before the search. It gets bigger.

  In addition, the navigation device 35 appropriately obtains the map drawing data and the road network data of the latest map data 7 of the mesh passing through the route based on the route information. The term “obtain appropriately” may be obtained following the route information, or as the moving body 9 moves, the map drawing data and the road network data of the latest map data 7 of the passing mesh may be sequentially obtained. Say good things. For example, it may be acquired at a timing when the communication load is reduced.

  In the offline case, the navigation device 35 cannot acquire the map drawing data and the road network data of the latest map data 7 from the server 31, and cannot acquire the route information from the server 31. Therefore, the navigation device 35 performs a route search using the pre-in map data 8. Therefore, in the case of offline, only the navigation device 35 does not communicate with the server 31 and can perform navigation based on the pre-in map.

  FIG. 7 is an example of a flowchart illustrating the operation of the navigation device 35 when the user searches for a route.

  First, the operation receiving unit 44 of the navigation device 35 receives a route search operation including a departure place and a destination (S301).

  In order to determine whether the route search is performed by the server 31 or the navigation device 35, the communication determination unit 52 determines whether or not online (S302).

  First, in the case of online (Yes in S302), the information requesting unit 42 transmits a route search request including a departure place and a destination to the server 31 via the first transmitting unit 41, and the first receiving unit 46 transmits the request to the server 31. The route information and the guidance information are acquired from (S303).

  Next, since the navigation screen drawing unit 48 has acquired the route information, the navigation requesting unit 42 requests the server 31 at least the map drawing data of the latest map data around the departure place and the road network data to the information requesting unit 42 (S304). The map data providing unit 15 specifies a mesh corresponding to an area including a route information + a buffer (a predetermined range around a display range), and outputs map drawing data of the latest map data of all meshes passing through the route and a road network. Get the data. Further, the latest map data may be automatically transmitted together with the route information.

  In the description of FIG. 7, the route information and the map drawing data of the latest map data are transmitted separately. However, the route information and the map drawing data of the latest map data may be transmitted collectively in step S303, for example. Good.

  Next, the navigation screen drawing unit 48 draws the latest map based on the map drawing data of the latest map data in the area 1, and the display processing unit 57 displays the latest map on the display device 213 (S305). That is, since it is online, the navigation screen drawing unit 48 draws the latest map in the area 1. As a result, the latest map is displayed on the display device 213.

  Further, the navigation screen drawing unit 48 displays the route on the display device 213 by drawing the route on the latest map in the area 1 (S306). Thus, the route searched by the latest map can be displayed on the latest map.

  Next, the navigation screen drawing unit 48 of the navigation device 35 draws a pre-in map based on the pre-in map data 8 in the area 2 (S307). Even if the user is online, the navigation screen drawing unit 48 always draws the pre-in map in the area 2. Thus, when the user goes offline, the latest map data 7 can be switched to the pre-in map data 8 and displayed without delay.

  In the case of offline (No in S302), the route search unit 51 performs a route search using the pre-in map data 8 (S308).

  Next, the navigation screen drawing unit 48 draws a pre-in map based on the pre-in map data in the area 2, and the display processing unit 57 causes the display device 213 to display the pre-in map (S309). That is, since the user is offline, the navigation screen drawing unit 48 draws a pre-in map in the area 2. As a result, the pre-in map is displayed on the display device 213.

  Also, the navigation screen drawing unit 48 displays the route on the display device 213 by drawing the route on the pre-in map of the area 2 (S310). Thus, the route searched by the pre-in map data 8 can be displayed on the pre-in map.

<When the latest map data can be used offline>
Next, a case where the latest map data 7 can be used offline will be described with reference to FIGS.

<< Judge whether there is the latest map data on the route >>
First, the determination of whether or not the latest map data 7 exists on the route searched by the pre-in map data 8 will be described with reference to FIG. FIG. 8 is a diagram illustrating an example of determining whether or not the latest map data 7 is present on the route 6 searched using the pre-in map data 8.

  First, it is assumed that the route information is a sequence of coordinate points. This coordinate point sequence is generated from the road network data of the pre-in map data 8. That is, the coordinate point sequence exactly overlaps the road in the pre-in map data 8. On the other hand, in the latest map data 7, since the road network may be different from the pre-in map data 8, the coordinate point sequence does not always overlap the road in the latest map data 7 exactly.

  In determining whether or not there is the latest map data 7 on the route, the base point setting unit 54 determines whether or not the mesh of the map drawing data stored in the latest map data storage unit 55 includes a coordinate point sequence. I do. Although it is preferable to make the determination for every coordinate point sequence, the determination may be made based on a coordinate point sequence sampled at regular intervals. As shown in Table 1, since the map drawing data includes a mesh area, comparison is easy (when the map drawing data is cached, the road network data is also cached). . In this way, all the meshes of the latest map data 7 on the route can be specified.

  In FIG. 8A, the latest map data 7 exists in the first half of the route 6 including the periphery of the departure point, and in FIG. 8B, the latest map data 7 exists in the second half of the route 6 including the periphery of the destination. I do. When a sufficient number of meshes exist on the route 6 as described above, the base point setting unit 54 determines whether the mesh of the map drawing data stored in the latest map data storage unit 55 includes a coordinate point sequence. I do. The road network of the latest map data 7 existing on the route specifies a node included in the mesh of the map drawing data including the coordinate point sequence from Table 2, and a link having the node as a start node or an end node. It is obtained by acquiring from the latest map data storage unit 55.

  On the other hand, in FIG. 8C, only one mesh exists on the route 6. Although the latest map data 7 exists on the route 6, it is considered that the effectiveness of searching only one mesh is not so great. Therefore, when the number of meshes of the latest map data 7 on the route 6 is small, the base point setting unit 54 may determine that the latest map data 7 does not exist on the route 6. Alternatively, the condition may be that the number of meshes continuously equal to or greater than the threshold exists. However, even if there is only one mesh on the route 6, it may be determined that the latest map data 7 exists on the route 6.

  FIGS. 8D to 8F show some variations when the latest map data 7 exists on the route. In FIG. 8D, there is no latest map data 7 around the departure point and the destination, and there is the latest map data 7 near the center of the route 6. In FIG. 8E, the latest map data 7 is present around the departure point and the destination. In FIG. 8 (f), there are the latest map data 7 around the departure point and the destination and near the center. The navigation device 35 of the present embodiment can correspond to any variation.

<< Road with the same attribute as the boundary between the latest map data and the pre-in map data >>
Next, a method of setting a base point will be described with reference to FIG. A base point is set at the boundary between the latest map data 7 and the pre-in map data 8, and a road having the same attribute as the base point is specified from the latest map data 7. FIG. 9 is a diagram illustrating an example of a route 6 and a road (link) corresponding to the route 6 at the boundary between the latest map data 7 and the pre-in map data 8. In this embodiment, the route 6 based on the pre-in map data 8 is searched.

  In FIG. 9A, there is no change in the mesh roads 303 and 304 at the boundary between the latest map data 7 and the pre-in map data 8. They are connected on a straight line. That is, there is no mismatch. Therefore, assuming that the boundary is the base point 301, a road 304 (a link having the same road attribute as the base point 301) on the route 6 can be found from the latest map data 7. That is, the coordinate point sequence of the route 6 matches the road 304. Since there is no inconsistency, the base point 301a of the pre-in map data 8 matches the base point 301b of the latest map data 7.

  On the other hand, in FIG. 9B, the road 304 of the latest map data 7 is changed, and the road on the side of the latest map data 7 and the road 303 on the side of the pre-in map data 8 are not connected in a straight line. That is, there is a mismatch. Therefore, the road 304 (a link having the same road attribute as the base point 301a) cannot be found on the route 6. In this case, using the coordinates of the route 6 at the boundary between the latest map data 7 and the pre-in map data 8 as the base point 301a, a search is made from the latest map data 7 for a road 304 having the same attribute within a predetermined distance from the base point 301a. The coordinates of the road 304 at the boundary between the latest map data 7 and the pre-in map data 8 are defined as a base point 301b.

  As described above, the base point setting unit 54 specifies the road 304 having the same attribute within a predetermined distance from the road 304 on the route 6 or the base point 301a. Then, the latest map data 7 is searched starting from the base point 301b of the road 304.

  A method for connecting the coordinate position of the base point 301b and the link of the road 304 will be described. This method is similar to a normal search for searching for a destination from a departure place such as a garage, for example. By the search, the coordinate position of the departure place and the link closest to the coordinate position of the departure place are connected. The route search unit 51 specifies a link closest to the coordinate position of the base point 301b or a link located within a predetermined distance from the coordinate position of the base point 301b, and searches for a route passing through the link.

  In this embodiment, since the destination may be searched from the base point 301b, the process of connecting the node of the pre-in map data 8 and the node of the latest map data 7 becomes unnecessary.

<Procedure for specifying the same road as the pre-in map data>
As described above, when the same road as the road corresponding to the route searched in the pre-in map data 8 can be specified from the latest map data 7, the navigation device 35 searches the route using the latest map data 7 even offline. be able to.

  FIG. 10 is an example of a flowchart illustrating a procedure for searching for a route using the latest map data 7 when the latest map data 7 can be used offline. Steps S401 to S404 may be the same as steps S301 to S308 in FIG.

  When the route search unit 51 performs a route search (S404), the base point setting unit 54 determines whether or not the latest map data 7 exists on the route (S405).

  If the determination in step S405 is No, the process proceeds to steps S419 and S420 because the latest map data 7 cannot be used. The processing in steps S419 and S420 is the same as steps S309 and S310 in FIG.

  If the determination in step S405 is Yes, the base point setting unit 54 determines the coordinates of the route 6 at the boundary between the latest map data 7 and the pre-in map data 8 and the road attribute of the route 6 in the pre-in map data 8 at the coordinates. It is obtained from the storage unit 56 (S406). For example, assuming that the route is a sequence of coordinate points, the coordinates of the route at the boundary between the latest map data 7 and the pre-in map data 8 that are first determined to have the latest map data 7 along the route, or along the route The coordinates of the route at the boundary between the latest map data 7 initially determined not to have the latest map data 7 and the pre-in map data 8 are specified. A link having the coordinates or a node that substantially matches the coordinates is acquired from the pre-in map data storage unit 56. In addition, the road type of this link is obtained from the link table. When the route information is given in a link list, a link that is in contact with the boundary between the latest map data 7 and the pre-in map data 8 may be specified.

  Next, the base point setting unit 54 determines whether or not a road having the same attribute as the route 6 is within a predetermined distance from the coordinates acquired in step S406 in the latest map data 7 (S407). For example, referring to FIGS. 9A and 9B, a road 304 having the same road attribute as the road attribute of the route 6 (road attribute of the road 303) is located within a predetermined distance from the coordinate point of the base point 301a. 7 is determined.

  If the determination in step S407 is Yes, the base point setting unit 54 sets the coordinate point where the road 304 intersects with the boundary of both maps as the base point for the route search of the latest map data 7 and the pre-in map data 8 (S408). ). For example, in the case of FIG. 9, the base point 301a is set as the base point of the pre-in map data 8, and the base point 301b is set as the base point of the latest map data 7.

  Next, the route search unit 51 searches for a route of the latest map data 7 using the base point set on the latest map data 7 side (S409).

  The route search unit 51 obtains the latest route shown in FIG. 8 by connecting the route 6 and the route searched in step S409 with the base point set in step S408 as a waypoint (S410).

  The navigation screen drawing unit 48 displays the pre-in map and / or the latest map (S411). The reason why “and / or” is used is that only the plain map is displayed on the display device, only the latest map is displayed, and both the plain map and the latest map are displayed. .

  The navigation screen drawing unit 48 displays the latest route acquired in step S410 on the map displayed in step S411 (S412).

  If the determination in step S407 is No, the base point setting unit 54 cannot acquire the link leading to the route 6 from the latest map data 7 even when referring to all the road attributes existing in the latest map data 7, A new route is searched without using it.

  The base point setting unit 54 refers to the latest map data 7 and the pre-in map data 8, and links road attributes (both sides) connected to both the latest map data 7 and the pre-in map data 8 at a boundary portion overlapping the route 6. (Links having the same road attribute) are searched (S413).

  Next, when there is a link of the road attribute connected in step S413, the base point setting unit 54 sets the coordinate point where the boundary and the link on the latest map data 7 overlap as the base point of the route search of the latest map data 7. Then, a coordinate point where the boundary and the link on the side of the pre-in map data 8 overlap is set as the base point of the route search of the pre-in map data 8 (S414). For example, referring to FIGS. 15A and 15B, it is assumed that roads 303 and 304 having a road attribute connected to both at the boundary are searched. In this case, the coordinate point 302b where the boundary and the road 304 on the latest map data 7 overlap is set as the base point of the route search of the latest map data 7, and the coordinate point 302a where the boundary and the road 303 on the pre-in map data 8 overlap is defined in the pre-in map. It is set as the base point of the route search of the data 8.

  The route search unit 51 searches the route of the latest map data 7 using the base point set on the latest map data 7 side, and searches the route of the plain map data 8 using the base point set on the plain map data 8 side ( S415).

  The route search unit 51 obtains the latest route by connecting both routes searched in step S415 with the base point set in step S414 as a waypoint (S416).

  Steps S417 and S418 may be the same as steps S411 and S412.

<< Example of route >>
An example of a route search will be described with reference to FIG.

  When the latest map data 7 exists on the route 6 as shown in FIG. 8A, the route search unit 51 updates the route (first route) from the base point 330 of the latest map data 7 to the departure point S with the latest map data. Search with map data 7. Note that the route (third route) from the base point 330 to the destination G has been searched for in the pre-in map data 8, so that no route search is necessary. The route search unit 51 connects the route 5 to the departure point S searched by the latest map data 7 and the route 6 between the base point 330 and the destination G searched by the pre-in map data 8. The route from the departure point to the destination is assumed.

  When the latest map data 7 exists on the route 6 as shown in FIG. 8B, the route search unit 51 determines the route (first route) to the base point 331 of the latest map data 7 and the destination G by using the latest map. Search by data 7. Since the route (third route) from the base point 331 to the departure point S has already been searched in the pre-in map data 8, no route search is necessary. The route search unit 51 connects the route 5 from the base point searched by the latest map data 7 to the destination G, and the route 6 between the base point 331 searched by the pre-in map data 8 and the departure place S. Then, a route from the departure point to the destination is set.

  When the latest island-shaped map data 7 exists on the route 6 as illustrated in FIG. 8D, the route search unit 51 determines the route 5 (second route) between the base point 332 and the base point 333 of the latest map data 7. Is searched with the latest map data 7. Since the route 6 (corresponding to the third route A and the third route B, respectively) from the base point 332 to the departure point S and the base point 333 to the destination G has been searched by the pre-in map data 8, no route search is necessary. . The route search unit 51 includes a route 6 between the base point 332 searched in the pre-in map data 8 and the departure point S, a route 5 between the base point 332 and the base point 333 searched in the latest map data 7, and a pre-in map. The route 6 between the base point 333 retrieved by the data 8 and the destination G is connected to form a route from the departure point to the destination.

  When the latest map data 7 exists on the route 6 as shown in FIG. 8E, the route search unit 51 determines the route 5 (first route A) from the base point 334 of the latest map data 7 to the departure point and the latest map data. The route 5 from the base point 335 of the map data 7 to the destination G is searched using the latest map data 7. Since the route 6 (fourth route) between the base point 334 and the base point 335 has been searched using the pre-in map data 8, no route search is necessary. The route search unit 51 includes a route 5 between the base point 334 and the departure point S searched by the latest map data 7, a route 6 between the base point 334 and the base point 335, and a base point searched by the latest map data 7. Route 335 and route 5 (first route B) between destinations G are connected to form a route from the starting point to the destination.

  When the latest map data 7 exists as shown in FIG. 8 (f), it is a combination of FIGS. 8 (d) and 8 (e). The route search unit 51 determines the route 5 between the base point 334 of the latest map data 7 and the starting point S, the route 6 between the base point 334 and the base point 332, and the route between the base point 332 and the base point 333 of the latest map data 7. Route 5, a route 6 between the base point 333 and the base point 335, and a route 5 between the base point 335 of the latest map data 7 and the destination G by connecting the route from the departure place to the destination. I do.

  Although it has been described above that the search for the pre-in map data 8 is not necessary, a route search may be performed again.

<Display example of electronic map>
FIG. 11 is a diagram illustrating a display example of a route on the electronic map displayed by the display device. As described above, the latest map and route based on the latest map data 7 are drawn in the area 1, and the pre-in map and route based on the pre-in map data 8 are drawn in the area 2.

  In the case of offline, the navigation screen drawing unit 48 has described that the latest map is not drawn in the area 1. However, when the base point setting unit 54 determines that the latest map data 7 can be used offline, the navigation screen drawing unit 48 48 draws the latest map in area 1. Of course, the display may be performed only when the latest map data 7 in the display range of the display device 213 is stored in the latest map data storage unit 55.

  In addition, when the latest map data 7 displayed by the display device 213 is not stored in the latest map data storage unit 55 offline, the user can use the pre-in map and the route because the pre-in map of the area 2 is displayed. In this case, nothing is drawn in area 1.

  When only a part of the latest map data in the display range of the display device 213 is cached, it is determined that the latest map data is not cached.

<Summary>
As described above, the navigation device 35 of the present embodiment can effectively utilize the latest map data 7 acquired from the server within a usable range, even when the navigation device 35 is offline. As a user, even a part of the route can travel on the route searched by the latest map data 7, and it is expected that the traveling time is shortened.

  In the first embodiment, the search for the pre-in map data 8 is premised, but it may be determined whether the search from the departure point to the destination can be performed only with the latest map data 7. If the search is possible, navigation can be performed using this route, and the processing of the first embodiment becomes unnecessary. In this embodiment, the functional block diagram of the navigation device 35 of the first embodiment is used.

  FIG. 12 is an example of a diagram illustrating a search using only the latest map data 7. In FIG. 12A, the mesh of the latest map data 7 is continuous from the departure point to the destination. Therefore, to make a simple determination, the route search unit 51 determines whether the meshes of the latest map data 7 are continuous from the departure point to the destination. On the other hand, in FIG. 12B, since the meshes of the latest map data 7 are not continuous from the departure point to the destination, it is determined that the route cannot be searched.

  The determination may be made based on whether or not the search can be actually performed using the latest map data 7. In the Dijkstra method, the cost to all the nodes connected to the departure place is calculated, so that the route can be calculated if it can be searched.

  However, when the latest map data 7 has a narrow range, the searched route may not be appropriate. For this reason, the route search unit 51 searches the pre-in map data 8 from the starting point to the destination, and compares the route searched in the pre-in map data 8 with the route searched in the latest map data 7. For example, if the route searched by the latest map data 7 has a longer arrival time or distance than the route searched by the pre-in map data 8, it is determined that the route cannot be searched.

  FIG. 13 is a flowchart of a procedure for determining whether or not the route search unit can search for a route using the latest map data 7. The process shown in FIG. 13 starts when the user searches for a route while the user is offline.

  The route search unit 51 determines whether a route search from the starting point to the destination can be performed using the latest map data 7 (S501).

  If the determination in step S501 is Yes, the route search unit 51 performs a route search using the latest map data 7, and the navigation screen drawing unit 48 displays the latest map data 7 on the display device 213 to provide route guidance (S502).

  If the determination in step S501 is No, as in the first embodiment, the navigation device uses the latest map data 7 as much as possible based on the pre-in map data 8 (S503).

  According to the present embodiment, it is first determined whether the latest map data 7 can be searched from the departure point to the destination, so that the latest map data 7 can be effectively used as much as possible off-line.

  In the second embodiment, when the route cannot be searched from the departure point to the destination in the latest map data 7, the route searched in the pre-in map data 8 is used. However, when the latest map data 7 can be used at least in part, the route searched by the pre-in map data 8 is not always optimal. In the present embodiment, when a route search from the departure point to the destination cannot be performed using the latest map data 7, a route is searched from each of the latest map data 7 and the pre-in map data 8 to obtain an optimal route from the departure point to the destination. The navigation device 35 will be described.

  First, a route search performed by the navigation device 35 of the present embodiment will be described with reference to FIG. As shown in FIG. 14, the route cannot be searched from the departure point to the destination using the latest map data 7. In this case, the navigation device 35 sets the base points A and C at the boundary between the latest map data 7 and the pre-in map data 8 by a predetermined method.

  More specifically, base points A and C are set so that an optimal route from the starting point to the destination is obtained. In this embodiment, since the route is not searched based on the pre-in map data 8, base points can be set by the number of links at the boundary between the latest map data 7 and the pre-in map data 8. Therefore, in the present embodiment, the base points A and C are determined by the round robin method. Details will be described later. FIG. 14A shows reference points A and C determined by the brute force method for reference.

  In this embodiment, when the base points A and C are determined, the optimum route is also determined. Therefore, in FIG. 14B, the route from the starting point S to the base point A, the route from the base point A to the base point C, and the route from the base point C to the destination G are connected to form a route from the starting point to the destination.

  According to the above-described processing, when a route cannot be searched from the departure point to the destination in the latest map data 7, both the latest map data 7 and the pre-in map data 8 can be searched for an optimum route.

<How to determine the base point>
A method of determining a base point will be described with reference to FIG. FIG. 15 is a diagram showing roads passing through the boundary between the latest map data 7 and the pre-in map data 8. In this embodiment, the route 6 has not been set yet. In FIG. 15A, the road 304 on the side of the latest map data 7 and the road 303 on the side of the pre-in map data 8 substantially coincide with each other at the boundary between the latest map data 7 and the pre-in map data 8. In addition, the base point setting unit 54 sets the base point 301 as a base point candidate because there is a road 304 that matches the road 303. That is, in the present embodiment, first, base point candidates are set.

  In FIG. 15B, there is an inconsistency between the road 304 on the latest map data 7 side and the road 303 on the pre-in map data 8 side. However, if the road 303 is within a predetermined distance from the base point candidate (that is, the boundary) and the road types of the road 303 and the road 304 are the same, the road 304 can be determined as a link candidate.

  In addition, it is preferable to determine the candidate of the base point in the highest (coarse) hierarchy as possible. This is because the number of high (coarse) hierarchical links is small, so that the base point can be narrowed, and there is a possibility that the link exists at a distant place, which is advantageous for route search. Therefore, it is preferable to find the link of the same road type within a predetermined distance in the link of the highest (coarse) hierarchy.

<How to determine the base point>
FIG. 16 is an example of a diagram illustrating a method of determining the base points A to D. As described with reference to FIG. 15, base point candidates are set at the boundary between the latest map data 7 and the pre-in map data 8. In FIG. 16A, a to d and e to h are set as base point candidates. In the latest map data 7, base point candidates a to d and e to h are specified. In FIG. 16A, some of the base point candidates in the latest map data 7 are omitted, but in practice, base point candidates can be set as a whole.

In this embodiment, since no route has been set yet, it is not known which of the base point candidates a to d is optimal and which of the base point candidates ef is optimum. Therefore, the base point setting unit 54 sets an optimum base point by the round robin method. The following procedure is an example.
(i) Search the latest map data 7 for a route from the base point candidates a to d of the latest map data 7 to the departure place.
(ii) The latest map data 7 is searched for a route from the base point candidates e to h of the latest map data 7 to the destination.
(iii) The route of the base point candidate a and the base point candidates e to h is searched in the pre-in map data 8. Similarly, for the base point candidates b to d, the route to the base point candidates e to h is searched in the pre-in map data 8. That is, the search is performed by brute force.
(iv) Evaluate all combinations of routes from the origin to the destination. For example, since the cost of each route (ease of movement determined from the travel time) has already been calculated, the costs may be summed. For example, the costs of the route of the starting point and the base point candidate a, the route of the base point candidate a and any of the base point candidates e to h, and the cost of the route between any of the base point candidates e to h and the destination are totaled.
(v) A route in which a plurality of routes having the lowest cost is connected is a route from the departure point to the destination.

  In this way, the optimum route can be determined by the brute force method, and the base points through which the optimum route passes are the base points A and C to be obtained. Therefore, it can be expected that a route in which a plurality of routes having the lowest cost combination is connected includes, for example, a route whose traveling time is shorter than or equal to the route obtained only with the pre-in map data of the first embodiment. .

  In the present embodiment, the layout variation of the latest map data 7 and the pre-in map data is the same as that in FIG. As shown in FIGS. 8D and 8F, the latest map data 7 may exist in an island shape with respect to the pre-in map data 8. In this case, as shown in FIG. A base point can occur throughout the circumference of 7. In this case, a route may be searched for all combinations. In the example of FIG. 16B, the base point setting unit 54 extracts two of the base point candidates a to l, and the route search unit 51 searches for a route using all combinations. For example, if there are N base point candidates, a route of N (N-1) / 2 is searched. The base point setting unit 54 connects these routes and the route on the side of the pre-in map data 8 to evaluate a combination of the routes.

  This will be described with reference to FIG. The route 6 is not set.

  When the latest map data 7 exists as shown in FIG. 8A, the route search unit 51 determines a route from all the candidates of the base point 330 at the boundary between the latest map data 7 and the pre-in map data 8 to the departure point S. Search using the latest map data 7. All the candidates for the base point 330 and the route to the destination G are searched in the pre-in map data 8. An optimum route is specified from a combination of the route on the latest map data 7 and the route on the pre-in map data 8, and a base point is determined from the route. FIG. 8B may be substantially the same as FIG. 8A.

  When the latest map data 7 exists as shown in FIG. 8D, the route search unit 51 determines the route between the latest map data 7 and the candidate of the base point 332, 333 of the boundary between the pre-in map data 8 by the latest map data 7. Search by. The route between the candidate of the base point 332 and the starting point of the boundary between the latest map data 7 and the pre-in map data 8 and the route between the candidate of the base point 333 and the destination are searched in the pre-in map data 8. From the combination of the route from the departure point to the latest map data 7, the route in the latest map data 7, and the route from the latest map data 7 to the destination, the route that is the optimal route is specified, and the base point is determined from the route. Decided.

  When the latest map data 7 exists as shown in FIG. 8E, the route search unit 51 searches the latest map data 7 for a route from all the candidates of the base point 334 to the departure place S. The route between all the candidates for the base point 334 (departure side) and all the candidates for the base point 335 (destination side) is searched in the pre-in map data 8. The route from all the candidates of the base point 335 to the destination G is searched by the latest map data 7. From the combination of the route of the latest map data 7 on the departure side, the route of the pre-in map data 8, and the route of the latest map data 7 on the destination side, the route that is the optimal route is specified, and the route is determined. Determines the base point. FIG. 8F may be substantially the same as FIGS. 8D and 8E.

<Operation procedure>
FIG. 17 is an example of a flowchart illustrating the operation of the navigation device 35 of the present embodiment.

  The route search unit 51 determines whether a route search from the departure point to the destination can be performed using the latest map data 7 (S601).

  If the determination in step S601 is Yes, the navigation screen drawing unit 48 displays the latest map data 7 on the display device 213 (S602).

  If the determination in step S601 is No, the navigation screen drawing unit 48 displays a search mode selection screen (S603). The search mode selection screen is a screen for the user to select how to use the latest map data 7. An example is shown in FIG.

  With the search mode selection screen, the user uses the latest map data 7 as much as possible based on the pre-in map data 8 (Example 1), and searches for an optimal route by combining the pre-in map data 8 and the latest map data 7 ( Either embodiment 3) or use only the pre-in map data 8 is selected.

  When the operation receiving unit 44 receives a selection to use the latest map data 7 as much as possible, the navigation device 35 uses the latest map data 7 as much as possible based on the pre-in map data 8 described in the first embodiment. The processing is performed (S605).

  When the operation receiving unit 44 receives the selection of searching for the optimal route by combining the pre-in map data 8 and the latest map data 7, the navigation device 35 performs the processing described in the present embodiment (S606).

  When the operation receiving unit receives a selection to use only the pre-in map data 8, the navigation device 35 performs a route search using only the pre-in map data 8 (S607).

  In this way, the user can search for a route in his / her favorite search mode, and when receiving a selection to search for an optimal route by combining the pre-in map data 8 and the latest map data 7, the user can use the pre-in map data. 8 and the latest map data 7 can be combined to search for an optimal route.

  FIG. 18 shows an example of a search mode selection screen. The search mode selection screen 401 includes a “use the latest map data as much as possible based on the pre-in map data” button 402, a “search for an optimal route by combining the pre-in map data 8 and the latest map data 7” button 403, and A “search route using only the pre-in map data 8” button 404 is provided. The user can select his / her favorite search mode.

<Summary>
As described above, when the navigation device 35 of the present embodiment cannot search for a route from the departure point to the destination using the latest map data 7, the navigation device 35 searches for a route from each of the latest map data 7 and the pre-in map data 8 and searches the route from the departure point. An optimal route to the destination can be determined.

<Other application examples>
As described above, the best mode for carrying out the present invention has been described using the embodiment. However, the present invention is not limited to such embodiment at all, and various modifications may be made without departing from the gist of the present invention. And substitutions can be added.

  For example, the configuration example in FIG. 5 and the like is divided according to main functions in order to facilitate understanding of processing by the server 31 and the navigation device 35. The present invention is not limited by the way of dividing the processing unit or the name. The processing of the server 31 and the navigation device 35 can be divided into more processing units according to the processing content. Further, it is also possible to divide the processing unit so that one processing unit includes more processing.

  The pre-in map data storage unit 56 is an example of a second map data storage unit, the latest map data storage unit 55 is an example of a first map data storage unit, and the pre-in map is an example of a second map. The latest map is an example of a first map, the communication determining unit 52 is an example of a communication determining unit, the base point setting unit 54 is an example of a base point setting unit, and the route searching unit 51 is an example of a route searching unit. It is. The latest map data management unit 45 is an example of a map data acquisition unit, and the display device 213 is an example of a display unit. Area 1 of the drawing area 49 is an example of a first drawing area, and area 2 of the drawing area 49 is an example of a second drawing area. The navigation screen drawing unit 48 is an example of a map drawing unit, and the display processing unit 57 is an example of a display processing unit.

9 moving body 31 server 35 navigation device 100 navigation system

Claims (10)

A navigation device capable of communicating with an information processing device via a network and acquiring first map data,
Communication determination means for determining whether communication with the information processing apparatus is possible,
Map data acquisition means for acquiring the first map data held by the information processing device;
First map data storage means for storing the first map data acquired by the map data acquisition means;
Second map data storage means for storing second map data in advance;
If the communication determining means determines that communication with the information processing device is not possible, a base point is set at a boundary between the first map data and the second map data stored in the first map data storing means. Base point setting means for setting
Display processing means for displaying a route searched using the base point as a transit point;
A navigation device comprising: A first route between the base point in the first map data and at least one of a departure point and a destination point, and a path between the two base points of the island-shaped first map data; Searching at least one of a second route with the first map data;
A third route between the base point of the second map data and at least one of a departure point and a destination point, and a third path between the two base points of the island-shaped second map data; And searching at least one of the four routes in the second map data,
At least one of the first route and the second route is connected to at least one of the third route and the fourth route, and the base point between the departure point and the destination is defined as a transit point. The navigation device according to claim 1, further comprising a route search unit that sets the route as a route. A first map based on the first map data acquired by the map data acquisition means and at least one of the first route and the second route are drawn in a first drawing area, and the first map Map drawing means for drawing a second map based on the second map data and at least one of the third route and the fourth route in a second drawing area,
At least one of the first map, the first route, and the second route in the first drawing area is displayed on the second map, the third route, and the fourth route in the second drawing area. 3. The navigation device according to claim 2, further comprising: display processing means for displaying on the display device with priority over at least one of the following. When the communication determining means determines that communication with the information processing device is not possible, the route searching means searches the second map data for a route between the departure place and the destination,
The base point setting means, when the first map data passing through the route is stored in the first map data storage means,
3. The navigation device according to claim 2, wherein the base point is set at a boundary between the first map data and the second map data through which the route passes. The base point setting means sets the coordinates of the route at a boundary between the first map data and the second map data as the base point of the second map data, and further sets the coordinates of the second map data. Identify the type of road at the boundary,
In the first map data, when there is a road within a predetermined distance from the coordinates of the base point and having the same type as the road type of the second map data,
The base point setting means sets a coordinate of the first map data at a boundary between the first map data and the second map data as a base point of the first map data;
The navigation device according to any one of claims 2 to 4, wherein the route search means searches for a route of the first map data using a base point of the first map data. In the first map data, when there is no road of the same type as the road type of the second map data within a predetermined distance from the coordinates of the base point,
The base point setting means sets the coordinates of the road of the first map data at the boundary between the first map data and the second map data as the base point of the first map data, and Setting the coordinates of the road of the second map data as the base point of the second map data;
The route searching means searches the first map data using the base point of the first map data, and searches the second map data using the base point of the second map data. The navigation device according to any one of claims 2 to 5, wherein: The route search means stores a route between the departure place and the destination in the first map data storage means when the communication determination means determines that communication with the information processing device is not possible. Determining whether the first map data can be searched,
When a route between the departure point and the destination can be searched for by the first map data stored in the first map data storage means, the route is determined between the departure point and the destination. The navigation device according to claim 2, wherein the navigation device is a route. When a route between the departure point and the destination cannot be searched for in the first map data stored in the first map data storage means,
The base point setting means sets a plurality of candidates for the base point at a boundary between the first map data and the second map data,
Determining one base point from a plurality of base point candidates by a predetermined method;
The first route between the base point and the starting point or the destination searched in the first map data, and the second path between the two base points of the island-shaped first map data; At least one of the routes,
The third route between the base point searched by the second map data and the starting point or the destination, and the fourth route between the two base points searched by the second map data. The navigation device according to claim 7, wherein at least one of the routes is connected to form a route between the departure point and the destination. When the route from the departure point to the destination cannot be searched in the first map data,
The navigation according to claim 3, wherein the map drawing means displays on the display device a selection screen for accepting whether to search for a route from a departure point to a destination in the second map data. apparatus. A navigation device that communicates with an information processing device via a network and can acquire first map data.
Communication determination means for determining whether communication with the information processing apparatus is possible,
Map data acquisition means for acquiring the first map data held by the information processing device and storing the first map data in a first map data storage means;
When the communication determining means determines that communication with the information processing apparatus is not possible, the first map data stored in the first map data storing means and the first map data stored in advance in the second map data storing means are stored. Base point setting means for setting a base point at the boundary of the second map data being set,
A program that functions as display processing means for displaying a route searched using the base point as a transit point.