JP5204734B2 - Navigation system, navigation device, navigation server, and navigation method - Google Patents

Description

  The present invention relates to a navigation system, a navigation device, a navigation server, and a navigation method.

  Conventionally, a navigation device that downloads necessary map data from a server or the like as appropriate without holding map data in advance has been disclosed.

  For example, in Patent Document 1, if necessary, the current position detected by the current position detection unit is notified to the map center via the communication unit, the map information is requested, and the map information acquired from the map center and the current position detection are disclosed. A navigation device is disclosed in which the current position detected from the means is combined and rendered, and displayed on a display unit.

  Patent Document 2 discloses a communication circuit that receives map information from a station that wirelessly distributes map information of a plurality of scales, and a control unit that selects a scale of map information received based on the reception strength of the communication circuit. A navigation device including the above is disclosed.

JP 2000-67385 A JP 2002-323324 A

  However, the conventional navigation device has a problem in that map data cannot be acquired when the communication is out of service range or when the communication state deteriorates rapidly.

  For example, the navigation device described in Patent Document 1 is configured to automatically acquire map information from a map center when the current position of a moving object reaches an adjacent area, but a map information acquisition request At times, there is a problem that map information cannot be obtained when the user is outside the communication range.

  Further, the navigation device described in Patent Document 2 is configured to select and receive a scale of map information according to the communication strength, but when the communication strength rapidly deteriorates, the map information is no longer displayed. It had a problem that it could not be acquired.

  The present invention has been made in view of the above problems, and can acquire detailed map data from a server. In addition, even when the state outside the communication range or the communication state deteriorates rapidly, the map is continuously acquired. It is an object to provide a navigation system, a navigation device, a navigation server, and a navigation method.

  In order to achieve such an object, the navigation system of the present invention can communicate with a navigation server including at least a storage unit and a control unit, and a navigation device including at least a display unit, a storage unit, and a control unit. A navigation system connected to the navigation server, wherein the storage unit of the navigation server includes detailed map data storage means for storing detailed map data, and the storage unit of the navigation device stores a wide area map data Data storage means, and the control unit of the navigation device, when the communication state determining means for determining the communication state with the navigation server, and the communication state determining means determines that the communication state is normal, An operation for transmitting the detailed map data acquisition request to the navigation server. If the communication state is determined to be not normal by the request transmission means, the detailed map data receiving means for receiving the detailed map data transmitted from the navigation server, and the communication state determination means, the wide area map data Wide area map data acquisition means for acquiring the wide area map data stored in the storage means, the detailed map data received by the detailed map data reception means, or the wide area map acquired by the wide area map data acquisition means Map data display means for displaying data on the display section, the control section of the navigation server, an acquisition request receiving means for receiving an acquisition request for the detailed map data transmitted from the navigation device; Based on the acquisition request received by the acquisition request receiving means, the corresponding Detailed map data acquisition means for acquiring fine map data from the detailed map data storage means; and detailed map data transmission means for transmitting the detailed map data acquired by the detailed map data acquisition means to the navigation device. It is characterized by having.

  In the navigation system according to the present invention, in the navigation system described above, when the communication state determination unit determines that the communication state is not normal, the control unit of the navigation device displays a current value on the display unit. The scale of the displayed detailed map data is stored in the storage unit, and when it is determined that the communication state has been restored to the normal state, the detailed map data is stored at the scale stored in the storage unit. The image display apparatus further includes a scale control unit that controls to be displayed on the display unit.

  The navigation system according to the present invention is characterized in that, in the navigation system described above, the communication state determination means monitors the communication state with the navigation server and makes the determination based on the communication state. .

  The navigation system according to the present invention is characterized in that, in the navigation system described above, the communication state is a communication strength level, a communication speed, a communication line type, and / or a communication range or a state outside the communication range. And

  In the navigation system according to the present invention, in the navigation system described above, the control unit of the navigation device further includes current position information acquisition means for acquiring current position information related to a current position of a user of the navigation device. The acquisition request transmission means transmits the acquisition request for the detailed map data to the navigation server based on the current position information.

  The navigation device of the present invention is a navigation device including at least a display unit, a storage unit, and a control unit, which is communicably connected to a navigation server including at least a storage unit. The unit stores detailed map data, the storage unit of the navigation device stores wide area map data, the control unit determines a communication state with the navigation server, and determines the communication state. When the determination unit determines that the communication state is normal, the acquisition request transmitting unit transmits the acquisition request for the detailed map data to the navigation server, and is acquired from the storage unit of the navigation server based on the acquisition request. The detailed map data to be transmitted is received from the navigation server. Wide-area map data receiving means and wide-area map data acquisition means for acquiring the wide-area map data stored in the storage unit of the navigation device when the communication state is determined to be not normal by the communication state determination means And the map data display means for displaying the detailed map data received by the detailed map data receiving means or the wide area map data acquired by the wide area map data acquiring means on the display unit. It is characterized by that.

  Further, the navigation server of the present invention is a navigation server including at least a control unit and a storage unit, which is communicably connected to a navigation device including at least a display unit and a storage unit. The storage unit stores wide area map data, the storage unit of the navigation server stores detailed map data, and the control unit is transmitted from the navigation device when the communication state is determined to be normal. An acquisition request receiving means for receiving an acquisition request for detailed map data, and a detailed map for acquiring the corresponding detailed map data from the storage unit of the navigation server based on the acquisition request received by the acquisition request receiving means The detailed map data acquired by the data acquisition means and the detailed map data acquisition means Detailed map data transmitting means for controlling to display the detailed map data or the wide area map data stored in the storage unit of the navigation device to be displayed on the display unit. It is characterized by.

  Further, the navigation method of the present invention is executed in a navigation system in which a navigation server including at least a storage unit and a control unit and a navigation device including at least a display unit, a storage unit, and a control unit are connected to be able to communicate with each other. In the navigation method, the storage unit of the navigation server includes detailed map data storage means for storing detailed map data, and the storage unit of the navigation device stores wide area map data. A communication state determination step for determining a communication state with the navigation server, executed by the control unit of the navigation device, and the communication state determination executed by the control unit of the navigation device. If the communication status is normal in step An acquisition request transmission step for transmitting an acquisition request for the detailed map data to the navigation server, and the detailed map data transmitted from the navigation device, which is executed by the control unit of the navigation server. Based on the acquisition request received in the acquisition request receiving step, the acquisition request receiving step receiving the acquisition request, and the acquisition request receiving step executed in the control unit of the navigation server, the corresponding detailed map data is converted into the detailed map. Detailed map data acquisition step acquired from the data storage means, and the detailed map data acquired in the detailed map data acquisition step executed in the control unit of the navigation server and transmitted to the navigation device Data transmission step and the above navigation A detailed map data receiving step for receiving the detailed map data transmitted from the navigation server, executed in the control unit of the navigation device, and a communication state determining step executed in the control unit of the navigation device. When the communication state is determined to be not normal, the wide area map data acquisition step for acquiring the wide area map data stored in the wide area map data storage means and the control unit of the navigation device are executed. A map data display step for displaying the detailed map data received in the detailed map data receiving step or the wide area map data acquired in the wide area map data acquiring step on the display unit. It is characterized by that.

  The navigation method of the present invention is a navigation method that is executed in a navigation device that includes at least a display unit, a storage unit, and a control unit, and is communicably connected to a navigation server that includes at least a storage unit. The storage unit of the navigation server stores detailed map data, the storage unit of the navigation device stores wide area map data, and determines a communication state with the navigation server, which is executed in the control unit. Based on the communication status determination step, the acquisition request transmission step of transmitting the acquisition request for the detailed map data to the navigation server when the communication status is determined to be normal in the communication status determination step, and the acquisition request Acquired from the storage unit of the navigation server and transmitted. The detailed map data is stored in the storage unit of the navigation device when it is determined that the communication state is not normal in the detailed map data receiving step for receiving from the navigation server and the communication state determining step. The wide area map data acquisition step for acquiring the wide area map data, the detailed map data received in the detailed map data reception step, or the wide area map data acquired in the wide area map data acquisition step. And a map data display step to be displayed on the display unit.

  The navigation method of the present invention is a navigation method executed in a navigation server having at least a control unit and a storage unit, which is communicably connected to a navigation device having at least a display unit and a storage unit. The storage unit of the navigation device stores wide-area map data, the storage unit of the navigation server stores detailed map data, and is executed in the control unit. When the communication state is determined to be normal The acquisition request receiving step for receiving the acquisition request for the detailed map data transmitted from the navigation device to the navigation device, and the corresponding detailed map data for the navigation based on the acquisition request received in the acquisition request receiving step. A detailed map data acquisition step acquired from the storage unit of the server; The detailed map data acquired in the detailed map data acquisition step is transmitted to the navigation device, and the detailed map data or the wide area map data stored in the storage unit of the navigation device is displayed on the display unit. And a detailed map data transmission step for controlling to be performed.

  According to this invention, the navigation server stores the detailed map data in the storage unit, the navigation device stores the wide-area map data in the storage unit, the navigation device determines the communication state with the navigation server, and the communication state When it is determined that the communication status is normal, the detailed map data acquisition request is transmitted to the navigation server, the detailed map data transmitted from the navigation server is received, and the communication status is determined to be normal, and is stored in the storage unit. The acquired wide area map data is acquired and the received detailed map data or the acquired wide area map data is displayed on the display unit, and the navigation server receives the acquisition request of the detailed map data transmitted from the navigation device. Based on the received acquisition request, the corresponding detailed map data is acquired from the storage unit and acquired. Fine map data, can be transmitted to the navigation device. As a result, the present invention can acquire detailed map data from the server, and can continuously display a map even when the state outside the communication range or the communication state deteriorates rapidly. Play. In particular, the present invention does not have a large-capacity storage or memory on the local (navigation device) side, and is applied to a navigation device that stores only wide-area map data with a small amount of data. Detailed map data is downloaded from the server only when the communication status is sufficient to download the map data, so the local (navigation device) side acquires and displays appropriate map data according to the communication status. There is an effect that can be.

  Further, according to the present invention, when the navigation device determines that the communication state is not normal, the navigation device stores the scale of the detailed map data currently displayed on the display unit in the storage unit, and the communication state is normal. When it is determined that the state has been recovered, the detailed map data can be controlled to be displayed on the display unit at the scale stored in the storage unit. Thus, the present invention can restore the scale of the detailed map data displayed on the display unit before the communication state deteriorates, and can display the map at a desired scale without giving the user a sense of incongruity. There is an effect.

  Further, according to the present invention, the navigation device can monitor the communication state with the navigation server and determine the communication state based on the communication state. Thereby, the present invention has an effect that it is possible to grasp the transition of the communication state and acquire appropriate map data according to the current communication state.

  Further, according to the present invention, the communication state can be a communication strength level, a communication speed, a communication line type, and / or a communication range or a state outside the communication range. Thus, according to the present invention, in order to download detailed map data depending on the communication strength, the communication speed, the type of the communication line, the communication status such as the communication range / out of communication range, etc. Even if it is insufficient, there is an effect that the map data can be continuously provided without giving the user a sense of incongruity.

  Further, according to the present invention, the navigation device can acquire current position information related to the current position of the user of the navigation device, and can transmit an acquisition request for detailed map data to the navigation server based on the current position information. it can. Thereby, this invention has an effect that the detailed map data containing the present position of the user of a navigation apparatus can be acquired.

  In the above description, the navigation system of the present invention has been described as an example. However, the navigation apparatus, the navigation server, and the navigation method have the same effect.

FIG. 1 is a block diagram showing an example of the configuration of the navigation system in the present embodiment. FIG. 2 is a flowchart showing an example of basic processing of the navigation system in the present embodiment. FIG. 3 is a diagram illustrating an example of a scale restoration process of the navigation system according to the present embodiment. FIG. 4 is a diagram illustrating an example of a detailed map data display screen displayed when the communication state is normal. FIG. 5 is a diagram illustrating an example of a display screen of wide area map data displayed when the communication state is not normal. FIG. 6 is a diagram illustrating an example of a detailed map data display screen displayed when the communication state is recovered.

  DESCRIPTION OF EMBODIMENTS Embodiments of a navigation system, a navigation device, a navigation server, a navigation method, and a program according to the present invention will be described below in detail with reference to FIGS. Note that the present invention is not limited to the embodiments.

[Navigation system configuration]
First, an example of the configuration of the navigation system in the present embodiment will be described below with reference to FIG. Here, FIG. 1 is a block diagram showing an example of the configuration of the navigation system in the present embodiment, and conceptually shows only the portion related to the present invention in the configuration.

  As shown in FIG. 1, the navigation system of this embodiment schematically includes a navigation server 200 including at least a control unit 202 and a storage unit 206, and a display unit 114, a control unit 102, and a storage unit 106. At least the navigation device 100 provided is configured to be communicable. The communication is, for example, remote communication such as wired / wireless communication via the network 300, and has a function of mutually connecting the navigation device 100 and an external device such as the navigation server 200. For example, the Internet, It may be a telephone line network (including a mobile terminal line network and a general telephone line network), an intranet, power line communication (PLC), or the like. Each unit of the navigation device 100 and the navigation server 200 is communicably connected via an arbitrary communication path.

[Configuration of Navigation Server 200]
Here, in FIG. 1, the navigation server 200 receives the detailed map data acquisition request transmitted from the navigation device 100, acquires the corresponding detailed map data from the storage unit 206 based on the received acquisition request, It has a function of transmitting the acquired detailed map data to the navigation device 100. The navigation server 200 is connected to the navigation apparatus 100 through the communication control interface unit 204 via the network 300 so as to be communicable with each other, and includes a control unit 202 and a storage unit 206. The control unit 202 is a control unit that performs various processes, and acquires and transmits detailed map data. The communication control interface unit 204 is an interface connected to a communication device (not shown) such as an antenna or a router connected to a communication line, a telephone line, etc., and performs communication control between the navigation server 200 and the network 300. It has a function to perform. That is, the communication control interface unit 204 has a function of communicating data with the navigation device 100 or the like via a communication line. The storage unit 206 is a storage unit such as a fixed disk device, and stores various databases and tables (such as a detailed map database 206a).

  Among these components of the storage unit 206, the detailed map database 206a is a map data storage unit that stores map data that is more detailed than the map data stored in advance in the navigation device 100. The detailed map data stored in the detailed map database 206a includes, for example, 1) map drawing data, 2) network data, 3) spot data, and the like.

  1) Map drawing data is data for drawing a map, for example, drawing data for drawing a landform such as a building, a road, or a mountain / river. For example, the drawing data may be data representing one area, site, area, or the like on a map with polygonal polygons, or data for two-dimensional display or three-dimensional display. Further, the drawing data may be outdoor map data such as road maps of the whole country and each region, and indoor map data such as a floor guide map relating to a building having height information (for example, a multilevel parking lot). There may be.

  2) Network data is data defining a traffic network, for example, data relating to roads and passages constituted by nodes and links. This network data is composed of, for example, a combination of node data related to nodes that are nodes in road network expression such as intersections and link data related to links that are road sections between nodes. More specifically, the node data may include a node number, position coordinates such as latitude and longitude, a node type, the number of links to be connected, a connection node number, an intersection name, and the like. The link data includes the link number, the type of road to be connected (whether it is an expressway or a general road, etc.), route numbers such as national roads, prefectural roads, and city roads, important route information, attribute information of administrative districts where links exist, Link length, road usage status, abnormal weather traffic restriction section, vehicle weight restriction, vehicle height restriction, width, road width classification, number of lanes, traffic speed restriction such as speed limit, in-link attributes such as overpasses, tunnels and bridges, and The name may be included.

  3) Spot data is data in which information is associated with a certain point. For example, facility information such as stores, notes (characters such as place names), icons (advertisements, etc.) are associated with latitude and longitude. Information such as additional icons, general icons, etc.) and symbols (such as map symbols) are stored.

  These various detailed map data are stored in advance in the detailed map database 206a, and the control unit 202 of the navigation server 200 periodically downloads the latest detailed map data via the network 300 and stores it in the detailed map database 206a. You may update the various detailed map data memorize | stored. Also, these various detailed map data may be configured in mesh units (for example, first to third mesh sections, 100 m mesh sections (1/10 subdivided mesh sections), etc.) partitioned by longitude and latitude. Good. The detailed map data stored in the detailed map database 206a may be raster format map data or vector format map data.

  The control unit 202 has an internal memory for storing a control program such as an OS (Operating System), a program that defines various processing procedures, and necessary data. And the control part 202 performs the information processing for performing various processes with these programs. The control unit 202 includes an acquisition request reception unit 202a, a detailed map data acquisition unit 202b, and a detailed map data transmission unit 202c in terms of functional concept.

  Among these, the acquisition request receiving unit 202 a is an acquisition request receiving unit that receives a map data acquisition request from the navigation device 100.

  The detailed map data acquisition unit 202b is a detailed map data acquisition unit that acquires detailed map data corresponding to the acquisition request received by the acquisition request reception unit 202a from the detailed map database 206a. For example, the detailed map data acquisition unit 202b acquires the corresponding detailed map data by extracting the corresponding detailed map data from the detailed map database 206a based on the map range, center coordinates, scale, and the like specified in the acquisition request. Further, when the current position information is added to the acquisition request, the detailed map data acquisition unit 202b may acquire the detailed map data corresponding to the current position information from the detailed map database 206a. Further, the data format of the detailed map data acquired by the detailed map data acquisition unit 202b may be a raster format or a vector format. For example, the detailed map data acquisition unit 202b stores the detailed map data in vector format in the detailed map database 206a. Is stored, the detailed map data in the vector format may be converted into the raster format at the scale specified in the acquisition request. Here, in the present embodiment, the “scale” is a reduction ratio for drawing a map with a size smaller than the actual size, for example, “1 / 25,000”, “1 / 50,000”, etc. Map size, map data mesh type (primary to tertiary mesh sections, 100m mesh section, etc.), distance on the map displayed per unit pixel of the display unit 114 of the navigation device 100 (1m, etc.) ). For example, when the detailed map data is stored in the detailed map database 206a in a plurality of mesh sections (primary to tertiary mesh sections, 100m mesh sections, etc.), the detailed map data acquisition unit 202b uses a scale in the acquisition request. Detailed map data of a specified mesh section may be acquired.

  The detailed map data transmission unit 202c is a detailed map data transmission unit that transmits the detailed map data acquired by the detailed map data acquisition unit 202b to the navigation device 100.

[Configuration of Navigation Device 100]
In FIG. 1, the navigation device 100 determines the communication state with the navigation server 200, and when the communication state is determined to be normal, the navigation device 100 transmits a detailed map data acquisition request to the navigation server 200 to obtain the detailed map data. When it is received from the navigation server 200 and it is determined that the communication state is not normal, the wide area map data stored in the wide area map database 106a is acquired, and the received detailed map data or the acquired wide area map data is It has a function of displaying on the display unit 114. In the present embodiment, the navigation device 100 is connected to the navigation server 200 via the network 300 via the communication control interface unit 104 so as to be able to communicate with each other. The control unit 202, the storage unit 206, and the display unit 114. And an input unit 116. Here, the navigation apparatus 100 may include a position acquisition unit 112 having a GPS function, an IMES function, or the like so that current position information can be acquired in real time.

  The navigation device 100 is, for example, an in-vehicle car navigation device that performs car navigation, an information processing device such as a desktop or notebook personal computer that is generally commercially available, a mobile navigation device such as a mobile phone, PHS, or PDA. It may be. Here, as an in-vehicle navigation device 100 that performs car navigation, for example, it is supplied with electric power from a vehicle, is detachably fixed to a vehicle main body such as a dashboard by an attachment or the like, and is largely connected to the device main body (local). It has no capacity storage and can acquire signals (for example, vehicle speed pulse, fuel consumption, etc.) from the vehicle, has a built-in communication module, and can communicate with the navigation server 200 and the like via the network 300 within the communication range. Yes, it is a device that can also download data such as map data from the navigation server 200.

  Of the configuration of the navigation device 100, the position acquisition unit 112 may be, for example, a position acquisition unit that receives a position information signal transmitted from the position transmission device 500. For example, the position acquisition unit 112 has a GPS function, an IMES function, and the like so that current position information can be acquired in real time. Here, the position transmitting device 500 may be a GPS device that transmits a position information signal (GPS signal) related to orbit data, time information, and the like, and uses a position information signal having characteristics similar to those of the GPS signal. An IMES device that realizes an IMES (Indoor Message System) technology that enables indoor positioning may be used. The IMES technology is a system developed from the framework of the quasi-zenith satellite, which is a positioning satellite system. Further, the position transmission device 500 may be a GPS repeater that transmits a GPS signal received outdoors indoors. Further, the position transmission device 500 may be a small transmission device that is arbitrarily installed at various locations on each floor in a building (for example, a multilevel parking lot). In addition, self-position information (position ID etc.) according to an installation place is allocated to this small transmitter. When the navigation device 100 enters the communicable range, the navigation device 100 receives the self-position information transmitted from the small transmitter as a position information signal. The communication method at this time may be, for example, various short-range wireless methods such as an RFID (Radio Frequency Identification) tag system and Bluetooth (registered trademark), an infrared communication method, and the like. Further, the position transmission device 500 may be a wireless LAN access point. In the present embodiment, the control unit 102 calculates position information including latitude, longitude, and height information from the position information signal acquired by the position acquisition unit 112. Further, the position acquisition unit 112 may receive the wireless LAN signal and acquire the identification information of the access point. In the present embodiment, the control unit 102 may acquire the position information by specifying the position of the access point from the identification information unique to the access point acquired by the position acquisition unit 112.

  In addition, the position acquisition unit 112, for example, based on the direction information such as the traveling direction of the navigation device 100 detected by the direction sensor, the distance information detected by the distance sensor, and the map data, the user of the navigation device 100 You may acquire the positional information which shows a present position. Here, a geomagnetic sensor that detects the absolute traveling direction of the navigation device 100 and an optical gyro that detects the relative traveling direction of the navigation device 100 may be used as the direction sensor. In addition, the direction sensor may be an electronic compass that can acquire information on the direction and inclination by combining a geomagnetic sensor and an acceleration sensor. Further, when the navigation device 100 is an in-vehicle information processing terminal, the distance sensor may generate a pulse corresponding to the rotation of the vehicle and detect the travel distance based on the number of rotations of the wheels. Further, when the navigation device 100 is an in-vehicle information processing terminal, the position acquisition unit 112 may acquire position information indicating the own vehicle position from inter-vehicle communication of a communication device mounted on each vehicle.

  Further, the display unit 114 is a display means (for example, a display composed of a liquid crystal, an organic EL, etc.) for displaying the detailed map data received from the navigation server 200, the wide area map data acquired from the wide area map database 106a, and the like. Monitor, etc.). The input unit 116 may be input means (for example, a key input unit, a touch panel, a keyboard, a microphone, etc.) for inputting a departure point, a current location, a destination, and the like. The input / output control interface unit 108 controls the position acquisition unit 112, the display unit 114, the input unit 116, and the like.

  The communication control interface unit 104 is an interface connected to a communication device (not shown) such as an antenna or a router connected to a communication line, a telephone line, etc., and communicates between the navigation device 100 and the network 300. It has a function to perform control. That is, the communication control interface unit 104 has a function of communicating data with the navigation server 200 or the like via a communication line.

  The storage unit 106 is a storage unit such as a fixed disk device or a cache memory, and stores various files, tables, and databases (a wide-area map database 106a, a detailed map data temporary file 106b, a scale state file 106c, etc.).

  Among these, the wide area map database 106 a is a wide area map data storage unit that stores map data that is wider than the map data stored in the detailed map database 206 a of the navigation server 200. For example, the wide area map data stored in the wide area map database 106a stores map data having a smaller scale than the detailed map data stored in the detailed map database 206a. As an example, when the mesh unit of the detailed map data is a 100 m mesh section (length of one side: about 100 m), the mesh unit of the wide area map data is a third mesh section (length of one side: about 1 km). Also good. Further, the wide area map data may be obtained by omitting some data items in the detailed map data and extracting only main data items, and the wide area map data is stored in advance without being updated. 106 may be stored. In other words, the wide area map data is rough and / or older than the detailed map data, and the wide area map data stored in the wide area map database 106a is stored in the detailed map database 206a. The data size is relatively smaller than the detailed map data.

  The detailed map data temporary file 106b is detailed map data storage means for storing the detailed map data received by the detailed map data receiving unit 102d. Here, the detailed map data temporary file 106b may temporarily store the detailed map data received by the detailed map data receiving unit 102d, and is configured using, for example, SRAM (Static Random Access Memory) or the like. A small-capacity high-speed memory (for example, a cache memory) may be used.

  The scale state file 106 c is a scale state storage unit for storing the scale of the detailed data currently displayed on the display unit 114.

  The control unit 102 includes an internal memory for storing a control program such as an OS, a program defining various processing procedures, and necessary data. And the control part 102 performs the information processing for performing various processes by these programs. The control unit 102 is functionally conceptually configured as a current position information acquisition unit 102a, a communication state determination unit 102b, an acquisition request transmission unit 102c, a detailed map data reception unit 102d, a wide area map data acquisition unit 102e, a map data display unit 102f, a scale. A control unit 102g is provided.

  Among these, the current position information acquisition unit 102a is current position information acquisition means for acquiring current position information related to the current position of the user of the navigation device 100. Here, the current position information acquisition unit 102 a is the navigation apparatus detected by the position information calculated from the position information signal received from the position transmission device 500 by the position acquisition unit 112 and / or the direction sensor of the position acquisition unit 112. The current position information of the user of the navigation device 100 including direction information such as the traveling direction of 100 may be acquired. Further, the current position information acquisition unit 102a may acquire, as current position information, position coordinates and the like regarding the current position input by the user via the input unit 116. Here, the current position input by the user via the input unit 116 may be a position where the user actually exists, and a virtual current position arbitrarily selected by the user (for example, Tokyo It may be an arbitrary point such as a station or an airport in Osaka selected by a user in the area. Specifically, the coordinates specified on the display screen displaying the map data displayed on the display unit 114 by the user via the input unit 116 (for example, specifying operation on the touch panel type display unit 114), And / or direction information may be acquired as current position information.

  The communication state determination unit 102b is a communication state determination unit that determines a communication state with the navigation server 200. For example, the communication state determination unit 102b monitors the communication state with the navigation server 200 and makes a determination based on the communication state. The communication state monitored by the communication state determination unit 102b includes the strength of communication strength, the communication speed, the type of communication line, the state within / out of communication range, and the like. For example, when the communication state determination unit 102b is in a communication state sufficient to receive the detailed map data transmitted from the navigation server 200 (for example, the communication strength is strong, the communication speed is fast, the communication line is thick, the communication The communication state is determined to be normal. On the other hand, if the communication state is insufficient to receive the detailed map data transmitted from the navigation server 200 (for example, the communication strength is weak, the communication speed is slow, the communication line is thin, In the case of being out of communication range), it is determined that the communication state is not normal.

  The acquisition request transmission unit 102c is an acquisition request transmission unit that transmits an acquisition request for detailed map data to the navigation server 200 when the communication state determination unit 102b determines that the communication state is normal. Here, the map data acquisition request may include, for example, information for designating a map range, scale, position (center coordinates, etc.), etc., and is centered on the current position of the user of the navigation device 100. For acquiring a map or the like, the current position information acquired by the current position information acquiring unit 102a may be included.

  The detailed map data receiving unit 102d is a detailed map data receiving unit that receives the detailed map data transmitted from the navigation server 200 and stores it in the detailed map data temporary file 106b.

  Moreover, the wide area map data acquisition part 102e acquires the wide area map data acquisition means which acquires the wide area map data memorize | stored in the present position information acquisition part 102a, when the communication state determination part 102b determines with a communication state not being normal. It is.

  The map data display unit 102f displays the detailed map data received by the detailed map data receiving unit 102d and stored in the detailed map data temporary file 106b, or the wide area map data acquired by the wide area map data acquiring unit 102e. It is a map data display means to be displayed on the unit 114. That is, for example, the map data display unit 102f displays the detailed map data stored in the detailed map data temporary file 106b on the display unit 114, and when there is no detailed map data corresponding to the detailed map data temporary file 106b, the details are displayed. Instead of the map data, the wide area map data acquired by the wide area map data acquisition unit 102e is displayed on the display unit 114. Here, the map data display unit 102f superimposes and displays a current position pointer based on the current position information acquired by the current position information acquisition unit 102a on a display screen for displaying detailed map data or wide area map data. If the display screen of the detailed map data including the current position pointer cannot be displayed, the display screen may be switched to the display screen of the wide area map data.

  The scale control unit 102g stores the scale of the detailed map data currently displayed on the display unit 114 in the scale state file 106c when the communication state determination unit 102b determines that the communication state is not normal. Scale control means for controlling the detailed map data to be displayed on the display unit 114 at the scale stored in the scale state file 106c when the communication state determination unit 102b determines that the communication state has been restored to the normal state. . That is, the scale control unit 102g restores the detailed map data to be displayed on the display unit 114 at the original scale when the communication state is restored to a normal state. For example, when the communication state determination unit 102b determines that the communication state has been restored to the normal state, the scale control unit 102g transmits a detailed map data acquisition request based on the scale stored in the scale state file 106c. The acquisition request transmission unit 102c may be controlled as described above. In addition, the scale control unit 102g receives the details received by the detailed map data receiving unit 102d and stored in the detailed map data temporary file 106b when the communication state determining unit 102b determines that the communication state has been restored to the normal state. The map data display unit 102f may be controlled so that the map data is displayed at a scale stored in the scale state file 106c.

  Above, description of an example of a structure of the navigation system in this embodiment is finished.

[Navigation system processing]
Next, an example of processing of the navigation system according to the present embodiment configured as described above will be described in detail below with reference to FIGS.

[Basic processing]
First, an example of the basic processing of the navigation system in the present embodiment will be described with reference to FIG. FIG. 2 is a flowchart showing an example of basic processing of the navigation system in the present embodiment.

  As shown in FIG. 2, first, the communication state determination unit 102b of the navigation device 100 monitors the communication state with the navigation server 200 to determine whether or not the communication state is normal (step SA-1). . For example, when the communication state determination unit 102b is in a communication state sufficient to receive the detailed map data transmitted from the navigation server 200 (for example, the communication strength is strong, the communication speed is fast, the communication line is thick, the communication When the communication state is determined to be normal and the communication state is insufficient to receive the detailed map data transmitted from the navigation server 200 (for example, the communication strength is If the communication state is weak, the communication speed is slow, the communication line is thin, or the communication area is out of service area, etc., it is determined that the communication state is not normal. In order to determine whether or not the communication state is normal, a threshold value may be set in advance in association with the communication state, and the communication state determination unit 102b may perform determination based on the threshold value.

  And the acquisition request transmission part 102c of the navigation apparatus 100 transmits the acquisition request of detailed map data to the navigation server 200, when the communication state determination part 102b determines with a normal communication state (step SA-1, Yes). (Step SA-2). Here, in order to acquire map data including the current position of the user of the navigation device 100, the acquisition request transmission unit 102c adds the current position information acquired by the current position information acquisition unit 102a and transmits an acquisition request. May be. The current position information acquisition unit 102a may acquire current position information from a position information signal transmitted from the position transmission device 500, and map data displayed on the display unit 114 to the user via the input unit 116. The coordinates specified on the display screen that displays (for example, the specifying operation on the touch panel display unit 114) and the azimuth information may be acquired as the current position information.

  Then, the acquisition request receiving unit 202a of the navigation server 200 receives a map data acquisition request from the navigation device 100 (step SA-3).

  And the detailed map data acquisition part 202b of the navigation server 200 acquires corresponding detailed map data from the detailed map database 206a based on the acquisition request received by the acquisition request reception part 202a (step SA-4). For example, the detailed map data acquisition unit 202b acquires the corresponding detailed map data by extracting it from the detailed map database 206a based on the map range, center coordinates, scale, current position information, and the like specified in the acquisition request. .

  And the detailed map data transmission part 202c of the navigation server 200 transmits the detailed map data acquired by the detailed map data acquisition part 202b to the navigation apparatus 100 (step SA-5).

  And the detailed map data receiving part 102d of the navigation apparatus 100 receives the detailed map data transmitted from the navigation server 200, and stores it in the detailed map data temporary file 106b (step SA-6).

  Thus, the navigation device 100 acquires the detailed map data from the navigation server 200 when the communication state determination unit 102b determines that the communication state is normal. On the other hand, in step SA-1 described above, the communication state is acquired. When the determination unit 102b determines that the communication state is not normal (No in step SA-1), the wide area map data acquisition unit 102e of the navigation device 100 converts the corresponding wide area map data into the current position information acquisition unit 102a. (Step SA-7).

  The map data display unit 102f of the navigation device 100 receives the detailed map data received by the detailed map data receiving unit 102d and stored in the detailed map data temporary file 106b, or the wide area map acquired by the wide area map data acquiring unit 102e. The data is displayed on the display unit 114 (step SA-8). That is, the map data display unit 102f displays the detailed map data stored in the detailed map data temporary file 106b on the display unit 114 when the communication state is normal, while the wide area when the communication state is not normal. The wide area map data acquired by the map data acquisition unit 102e is displayed on the display unit 114. Here, the map data display unit 102f superimposes and displays a current position pointer based on the current position information acquired by the current position information acquisition unit 102a on a display screen for displaying detailed map data or wide area map data. You may let them. In addition, the navigation device 100 may require new map data, such as when the current position information cannot be displayed on the map display screen due to an update of the current position information acquired by the current position information acquisition unit 102a. In step SA-1, the processing is returned to and the detailed map data or the wide area map data is acquired and displayed again. The above is an example of the basic processing of the navigation system in the present embodiment.

[Scale restoration processing]
Next, the scale restoration processing of the navigation system in the present embodiment will be described below with reference to FIG. In this scale restoration process, assuming that the communication state has deteriorated from the normal state and has returned to the normal state again, the scale of the detailed map data is not to be given to the user when the normal state is restored. One purpose is to restore and display. Here, FIG. 3 is a diagram showing an example of the scale restoration process of the navigation system in the present embodiment.

  As shown in FIG. 3, the map data display unit 102f of the navigation device 100 receives the detailed map data temporary file received by the detailed map data receiving unit 102d when the communication state is normal, as in step SA-8 described above. The detailed map data stored in 106b is displayed on the display unit 114 (step SB-1). Here, FIG. 4 is a diagram illustrating an example of a detailed map data display screen displayed when the communication state is normal. As shown in FIG. 4, for example, the map data display unit 102f displays detailed map data of a 100 m mesh section (length of one side: about 100 m) stored in the detailed map data temporary file 106b on the display unit 114. Let

  Then, the acquisition request transmission unit 102c of the navigation device 100 newly adds a case where the current position cannot be displayed on the detailed map data display screen by updating the current position information acquired by the current position information acquisition unit 102a. It is determined whether map data is necessary (step SB-2).

  When the acquisition request transmission unit 102c determines that map data is newly required (step SB-2, Yes), the communication state determination unit 102b of the navigation device 100 monitors the communication state with the navigation server 200. Then, it is determined whether or not the communication state is normal (step SB-3). On the other hand, when the acquisition request transmission unit 102c determines that new map data is not necessary (No in step SB-2), the map data display unit 102f of the navigation device 100 continues to display the detailed map data on the display unit 114. (Step SB-1).

  When the communication state determining unit 102b determines that the communication state is normal (step SB-3, Yes), as in step SA-2 described above, the acquisition request transmitting unit 102c of the navigation device 100 performs detailed map data. Is transmitted to the navigation server 200, the processing after step SA-2 is performed. In this case, the scale restoration processing is not necessary.

  On the other hand, when the communication state determination unit 102b determines that the communication state is not normal (step SB-3, No), the scale control unit 102g of the navigation device 100 displays the detailed map data currently displayed on the display unit 114. Are stored in the scale state file 106c (step SB-4). For example, when the display screen shown in FIG. 4 is displayed, the scale control unit 102g uses the type of mesh section (for example, 100 m mesh) as the scale of the detailed map data currently displayed on the display unit 114, A distance (1 m or the like) on the map to be displayed per unit pixel of the display unit 114 may be stored in the scale state file 106c.

  And the wide area map data acquisition part 102e of the navigation apparatus 100 acquires corresponding wide area map data from the wide area map database 106a (step SB-5).

  And the map data display part 102f of the navigation apparatus 100 displays the wide area map data acquired by the wide area map data acquisition part 102e on the display part 114 (step SB-6). Here, FIG. 5 is a diagram showing an example of a display screen of wide area map data displayed when the communication state is not normal. As shown in FIG. 5, as an example, the map data display unit 102f displays a wide area map data when the wide area map database 106a stores wide area map data of the third mesh section (length of one side: about 1 km). The wide area map data acquired by the map data acquisition unit 102e is displayed on the display unit 114.

  Then, the communication state determination unit 102b of the navigation device 100 determines whether or not the communication state has been restored to a normal state (step SB-7).

  If the communication state determination unit 102b determines that the communication state has not recovered to a normal state (step SB-7, No), the process returns to step SB-5 and a necessary wide area by the wide area map data acquisition unit 102e. The map data acquisition process and the wide area map data display process by the map data display unit 102f are continued.

  On the other hand, when the communication state determination unit 102b determines that the communication state has been restored to the normal state (step SB-7, Yes), the acquisition request transmission unit 102c of the navigation device 100 receives the acquisition request for detailed map data. Is transmitted to the navigation server 200 (step SB-8). Here, the scale control unit 102g controls the acquisition request transmission unit 102c so that an acquisition request for acquiring detailed map data is transmitted at a scale (for example, a 100 m mesh section) stored in the scale state file 106c. Also good.

  Then, the acquisition request receiving unit 202a of the navigation server 200 receives a map data acquisition request from the navigation device 100 (step SB-9).

  And the detailed map data acquisition part 202b of the navigation server 200 acquires corresponding detailed map data from the detailed map database 206a based on the acquisition request received by the acquisition request reception part 202a (step SB-10). Here, when the scale is specified in the acquisition request, the detailed map data acquisition unit 202b acquires the detailed map data of the scale from the detailed map database 206a.

  And the detailed map data transmission part 202c of the navigation server 200 transmits the detailed map data acquired by the detailed map data acquisition part 202b to the navigation apparatus 100 (step SB-11).

  The detailed map data receiving unit 102d of the navigation device 100 receives the detailed map data transmitted from the navigation server 200 and stores it in the detailed map data temporary file 106b (step SB-12).

  Then, the scale control unit 102g of the navigation device 100 changes the map data display unit 102f so that the detailed map data stored in the detailed map data temporary file 106b is displayed on the display unit 114 at the scale stored in the scale state file 106c. By performing the control, the scale is restored (step SB-13). Here, FIG. 6 is a diagram illustrating an example of a detailed map data display screen displayed when the communication state is recovered. As an example, as shown in FIG. 6, the map data display unit 102 f displays on the display unit 114 at a scale (for example, a 100 m mesh section or a distance 1 m on a map per unit pixel) stored in the scale state file 106 c. As described above, the detailed map data stored in the detailed map data temporary file 106b is displayed on the display unit 114 after performing drawing processing such as enlargement / reduction if necessary.

  The above is an example of the scale restoration process of the navigation system in the present embodiment. Thereby, the scale of the detailed map data displayed on the display unit 114 before the communication state deteriorates can be restored, and the map can be displayed at a desired scale without giving the user a sense of incongruity.

  Above, description of the process of the navigation system in this embodiment is finished.

[Other embodiments]
Although the embodiments of the present invention have been described so far, the present invention can be implemented in various different embodiments within the scope of the technical idea described in the claims other than the above-described embodiments. It may be done.

  In addition, among the processes described in the embodiment, all or part of the processes described as being automatically performed can be performed manually, or the processes described as being performed manually can be performed. All or a part can be automatically performed by a known method.

  In addition, processing procedures, control procedures, specific names, information including parameters such as registration data and facility search conditions, screen examples, and database configurations shown in the above documents and drawings may be specially noted. It can be arbitrarily changed except for.

  Further, regarding the navigation device 100 and the navigation server 200, each illustrated component is functionally conceptual and does not necessarily need to be physically configured as illustrated.

  For example, the processing functions provided in each device of the navigation device 100 and the navigation server 200, in particular, the processing functions performed by the control unit 102 and the control unit 202 are all or any part of the processing functions. (Central Processing Unit) and a program interpreted and executed by the CPU, or can be realized as hardware by wired logic. The program is recorded on a recording medium to be described later, and is mechanically read by the navigation device 100 and the navigation server 200 as necessary. That is, the storage unit 206 such as a ROM or HD stores a computer program for performing various processes by giving instructions to the CPU in cooperation with the OS. This computer program is executed by being loaded into the RAM, and constitutes a control unit in cooperation with the CPU.

  The computer program may be stored in the navigation apparatus 100 and an application program server connected to the navigation server 200 via an arbitrary network 300, and the computer program may be wholly or partially stored as necessary. It can also be downloaded.

  The program according to the present invention can also be stored in a computer-readable recording medium. Here, the “recording medium” is an arbitrary “portable physical medium” such as a flexible disk, a magneto-optical disk, a ROM, an EPROM, an EEPROM, a CD-ROM, an MO, a DVD, a Blu-ray Disc, or the like. It includes a “communication medium” that holds a program in a short period of time, such as a communication line or a carrier wave when a program is transmitted via a network represented by a LAN, WAN, or the Internet.

  The “program” is a data processing method described in an arbitrary language or description method, and may be in any format such as source code or binary code. Note that the “program” is not necessarily limited to a single configuration, and functions are achieved in cooperation with a separate configuration such as a plurality of modules and libraries or a separate program represented by the OS. Including things. Note that a well-known configuration and procedure can be used for a specific configuration for reading a recording medium, a reading procedure, an installation procedure after reading, and the like in each device described in the embodiment.

  Various databases and the like (detailed map database 206a, wide area map database 106a to scale state file 106c, etc.) stored in the storage unit 106 and the storage unit 206 are RAM, a memory device such as a ROM, a fixed disk device such as a hard disk, a flexible It is a storage means such as a disk or an optical disk, and stores various programs, tables, databases, web page files, etc. used for various processes and website provision.

  Further, the navigation device 100 and the navigation server 200 connect information processing apparatuses such as known personal computers and workstations, and software (including programs, data, etc.) that allows the information processing apparatus to implement the method of the present invention. It may be realized by mounting.

  Furthermore, the specific form of distribution / integration of the devices is not limited to that shown in the figure, and all or a part of them may be functional or physical in arbitrary units according to various additions or according to functional loads. Can be distributed and integrated.

  As described above in detail, according to the present invention, detailed map data can be acquired from the server, and the map is continuously displayed even when the state outside the communication range or the communication state deteriorates rapidly. The navigation system, the navigation device, the navigation server, and the navigation method can be provided, which is extremely useful in various fields such as information devices that support navigation and the information processing field.

100 Navigation device 102 Control unit
102a Current position information acquisition unit
102b Communication state determination unit
102c Acquisition request transmission unit
102d Detailed map data receiver
102e Wide area map data acquisition unit
102f Map data display section
102g Scale control unit 104 Communication control interface unit 106 Storage unit
106a Wide area map database
106b Temporary map data temporary file
106c scale state file 108 input / output control interface unit 112 position acquisition unit 114 display unit 116 input unit 200 navigation server 202 control unit
202a Acquisition request receiver
202b Detailed map data acquisition unit
202c Detailed map data transmission unit 204 Communication control interface unit 206 Storage unit
206a Detailed map database 300 Network 500 Location transmitter

Claims (7)

A navigation system in which a navigation server including at least a storage unit and a control unit, and a navigation device including at least a display unit, a storage unit, and a control unit are communicably connected,
The storage unit of the navigation server includes:
Detailed map data storage means for storing detailed map data,
With
The storage unit of the navigation device includes:
Wide area map data storage means for storing wide area map data;
With
The control unit of the navigation device includes:
Communication state determination means for determining a communication state with the navigation server;
An acquisition request transmitting means for transmitting an acquisition request for the detailed map data to the navigation server when the communication state is determined to be normal by the communication state determining means;
Detailed map data receiving means for receiving the detailed map data transmitted from the navigation server;
Wide area map data acquisition means for acquiring the wide area map data stored in the wide area map data storage means when the communication state determination means determines that the communication state is not normal;
Map data display means for displaying the detailed map data received by the detailed map data receiving means or the wide area map data acquired by the wide area map data acquiring means on the display unit;
When the communication state determination means determines that the communication state is not normal, the scale of the detailed map data currently displayed on the display unit is stored in the storage unit, and the communication state is normal Scale control means for controlling the detailed map data to be displayed on the display unit at the scale stored in the storage unit when it is determined that
With
The control unit of the navigation server is
An acquisition request receiving means for receiving an acquisition request for the detailed map data transmitted from the navigation device;
Detailed map data acquisition means for acquiring the corresponding detailed map data from the detailed map data storage means based on the acquisition request received by the acquisition request reception means;
Detailed map data transmitting means for transmitting the detailed map data acquired by the detailed map data acquiring means to the navigation device;
A navigation system characterized by comprising: The navigation system according to claim 1 ,
The communication state determination means includes
A navigation system, wherein the communication state with the navigation server is monitored and the determination is made based on the communication state. The navigation system according to claim 1 or 2 ,
The navigation system according to claim 1, wherein the communication state is a communication strength level, a communication speed, a communication line type, and / or a communication range or a state outside the communication range. The navigation system according to any one of claims 1 to 3 ,
The control unit of the navigation device includes:
Current position information acquisition means for acquiring current position information relating to the current position of the user of the navigation device;
Further comprising
The acquisition request transmission means includes
A navigation system, wherein the detailed map data acquisition request is transmitted to the navigation server based on the current position information. A navigation device including at least a display unit, a storage unit, and a control unit, connected to a navigation server including at least a storage unit so as to be able to communicate,
The storage unit of the navigation server includes:
Memorize detailed map data,
The storage unit of the navigation device includes:
Memorize wide area map data,
The control unit
Communication state determination means for determining a communication state with the navigation server;
An acquisition request transmitting means for transmitting an acquisition request for the detailed map data to the navigation server when the communication state is determined to be normal by the communication state determining means;
Detailed map data receiving means for receiving the detailed map data acquired and transmitted from the storage unit of the navigation server based on the acquisition request from the navigation server;
Wide area map data acquisition means for acquiring the wide area map data stored in the storage unit of the navigation device when the communication state determination means determines that the communication state is not normal;
Map data display means for displaying the detailed map data received by the detailed map data receiving means or the wide area map data acquired by the wide area map data acquiring means on the display unit;
When the communication state determination means determines that the communication state is not normal, the scale of the detailed map data currently displayed on the display unit is stored in the storage unit, and the communication state is normal Scale control means for controlling the detailed map data to be displayed on the display unit at the scale stored in the storage unit when it is determined that
A navigation device comprising: A navigation method executed in a navigation system in which a navigation server including at least a storage unit and a control unit, and a navigation device including at least a display unit, a storage unit, and a control unit are connected to be communicable,
The storage unit of the navigation server includes:
Detailed map data storage means for storing detailed map data,
With
The storage unit of the navigation device includes:
Wide area map data storage means for storing wide area map data;
With
Executed in the control unit of the navigation device;
A communication state determination step for determining a communication state with the navigation server;
Executed in the control unit of the navigation device;
An acquisition request transmission step of transmitting an acquisition request for the detailed map data to the navigation server when the communication state is determined to be normal in the communication state determination step;
Executed in the control unit of the navigation server,
An acquisition request receiving step for receiving an acquisition request for the detailed map data transmitted from the navigation device;
Executed in the control unit of the navigation server,
Based on the acquisition request received in the acquisition request reception step, a detailed map data acquisition step of acquiring the corresponding detailed map data from the detailed map data storage unit;
Executed in the control unit of the navigation server,
A detailed map data transmitting step for transmitting the detailed map data acquired in the detailed map data acquiring step to the navigation device;
Executed in the control unit of the navigation device;
A detailed map data receiving step for receiving the detailed map data transmitted from the navigation server;
Executed in the control unit of the navigation device;
When it is determined in the communication state determination step that the communication state is not normal, the scale of the detailed map data currently displayed on the display unit is stored in the storage unit, and the wide area map data storage unit A wide area map data acquisition step for acquiring the wide area map data stored in
Executed in the control unit of the navigation device;
A map data display step for displaying the detailed map data received in the detailed map data receiving step or the wide area map data acquired in the wide area map data acquiring step on the display unit;
Only including,
In the map data display step,
A navigation method comprising: controlling the detailed map data to be displayed on the display unit at the scale stored in the storage unit when it is determined that the communication state is restored to a normal state . A navigation method executed in a navigation device including at least a display unit, a storage unit, and a control unit, connected to a navigation server including at least a storage unit in a communicable manner,
The storage unit of the navigation server includes:
Memorize detailed map data,
The storage unit of the navigation device includes:
Memorize wide area map data,
Executed in the control unit,
A communication state determination step for determining a communication state with the navigation server;
An acquisition request transmission step of transmitting an acquisition request for the detailed map data to the navigation server when the communication state is determined to be normal in the communication state determination step;
A detailed map data receiving step of receiving from the navigation server the detailed map data acquired and transmitted from the storage unit of the navigation server based on the acquisition request;
When it is determined in the communication state determination step that the communication state is not normal, the scale of the detailed map data currently displayed on the display unit is stored in the storage unit, and the storage of the navigation device A wide area map data acquisition step for acquiring the wide area map data stored in the section;
A map data display step for displaying the detailed map data received in the detailed map data receiving step or the wide area map data acquired in the wide area map data acquiring step on the display unit;
Only including,
In the map data display step,
A navigation method comprising: controlling the detailed map data to be displayed on the display unit at the scale stored in the storage unit when it is determined that the communication state is restored to a normal state .

Images