JP7145712B2 - Map data download method and map recording device - Google Patents

Description

The present disclosure relates to a map data download method and a map recording device.

In the map information updating method of the conventional movement guidance device, when updating the map information stored in the storage medium to new map information, the map update information is acquired from the external server and stored in the map information storage medium. Before the update of the map information is completed, the information to be used for movement guidance of the mobile object is first acquired from the external server for the area where the mobile object is expected to move along the guide route.

JP 2016-125952 A

In the conventional method, the update target area of the map information is the four areas centered on the current position of the vehicle. Information is also obtained from an external server. For this reason, there is a problem that the acquisition of map information in the area after the vehicle has passed is useless because it is unnecessary for movement guidance.

The present disclosure has been made with a focus on the above problems, and aims to provide a map data download method and a map recording device that eliminate unnecessary downloads of map data and provide appropriate route guidance to users. and

To achieve the above object, the present disclosure provides communication between an external server that stores server map data and a user controller that executes route guidance based on user map data and a travel guidance route stored in a memory. This is a map data download method. When the user controller downloads the server map data from the departure point to the destination by communication with the external server, dividing it into section map data for each section for each guidance point on the driving guidance route, the following things are performed. conduct. First, the required travel time required to travel a predetermined section from one guidance point to the next guidance point is predicted. Next, a required download time required to download the section map data of a predetermined section is predicted. Next, the required travel time and the required download time are compared. Next, out of the first information and the second information that constitute the section map data, the first information that is used for route guidance at the next guidance point in the predetermined section and has a data amount smaller than that of the second information is compared as a time comparison result. Download regardless. Then, when it is determined from the time comparison result that the required travel time is less than or equal to the required download time, the second information is not downloaded, and when it is determined that the required travel time is longer than the required download time, the first information is downloaded. After the end, the second information is downloaded.

In this way, it is possible to eliminate unnecessary downloading of map data and provide appropriate route guidance to the user. In addition, it is possible to reliably download the guide information within the travel time. To surely download guidance information necessary for route guidance in time for the next guidance point, and to surely perform route guidance.

1 is an overall system diagram showing configurations of a navigation device and an external server of Example 1. FIG. 3 is a block diagram showing a control block configuration of the navigation control unit of Example 1; FIG. FIG. 4 is an explanatory diagram showing prediction of required travel time and required download time, determination of time comparison, and download of section map data according to the first embodiment; 4 is a flow chart showing the flow of external server processing executed by the external server of the first embodiment; 4 is a flow chart showing the flow of route guidance processing executed by the navigation control unit of embodiment 1; 4 is a flow chart showing the flow of download processing executed by the navigation control unit of embodiment 1. FIG. FIG. 10 is an operation explanatory diagram showing the download operation of the embodiment 1; 4 is a flow chart showing the flow of new/old notification processing executed by the navigation control unit of the first embodiment; FIG. 10 is a diagram showing an example of guidance route information displayed when map data versions match in the HMI device of Example 1; FIG. 8 is a diagram showing an example of guidance route information display and old information display that are displayed when map data versions do not match in the HMI device of Example 1; FIG. 11 is an explanatory diagram showing prediction of total required travel time and total required download time, determination of time comparison, and download of section map data in Example 2; 10 is a flow chart showing the flow of download processing executed by the navigation control unit of embodiment 2. FIG. FIG. 10 is an operation explanatory diagram showing the download operation of the second embodiment;

Embodiments for implementing a map data download method and a map recording device according to the present disclosure will be described below based on Embodiments 1 and 2 shown in the drawings.

The map data download method and the map recording device in the first embodiment are applied to a car navigation system mounted on a vehicle. Hereinafter, the configuration of the first embodiment will be described by dividing it into the "whole system configuration" and the "main part configuration of the navigation control unit".

Based on FIG. 1, the overall system configuration will be described.

It has a navigation device 1 and an external server 100 as an overall system configuration.

The navigation device 1 includes an in-vehicle sensor 2, a map data storage section 3 (memory), a navigation control unit 4 (user controller), a touch panel 5, and an HMI device 6 (notification device).

The in-vehicle sensor 2 has a GPS 21 , a gyro sensor 22 , a vehicle speed sensor 23 and an in-vehicle data communication device 24 . Sensor information acquired by the vehicle-mounted sensor 2 is output to the navigation control unit 4 .

The GPS 21 is a vehicle position sensor that has a GNSS antenna 21a and uses satellite communication to detect the vehicle position (latitude and longitude) while the vehicle is stopped/running. In addition, the GPS 21 may have poor accuracy in detecting the position of the vehicle in tunnels or sections with relatively many buildings. Based on this, the vehicle position is estimated by calculation. Here, "GNSS" is an abbreviation for "Global Navigation Satellite System", and "GPS" is an abbreviation for "Global Positioning System".

The gyro sensor 22 is a sensor that detects the traveling direction of the vehicle, and the vehicle speed sensor 23 is a sensor that detects the speed of the vehicle.

The in-vehicle data communication device 24 performs wireless communication with the external data communication device 101 via the transmission/reception antennas 24a and 101a, thereby transmitting information and requests of the navigation device 1, and transmitting information and requests according to the requests. It is an external data sensor that acquires data from an external server 100 .

The map data storage unit 3 is configured by an in-vehicle memory that stores stored map data (user map data) in which latitude/longitude and map information are associated with each other. The stored map data has road information associated with each point. The road information includes information specifying a road by its position/area, road type for each road, lane width for each road, and road shape information. Furthermore, the position of the intersection, the approach direction of the intersection, the type of the intersection, and other information related to the intersection are stored in association with the identification information of each road link. Furthermore, for each road link identification information, road type, lane width, road shape, whether to go straight, priority of progress, whether to overtake (whether to enter adjacent lane), speed limit, signs, etc. Information about roads is associated and stored.

Here, the stored map data includes background map information and node information. "Background map information" is road information, terrain information, and facility information, and includes two-dimensional map data, three-dimensional map data, and enlarged display data displayed at intersections and the like. The “node information” is information of latitude and longitude nodes (coordinate points) provided at predetermined intervals in the road information. Background map information and node information also contain version information for that information. Further, when the travel guidance route is generated, the node information includes guidance information for the vehicle to travel along the travel guidance route. "Guidance information" is used for route guidance, and is direction information at each node on the travel guidance route, for example, right turn or left turn information. The guidance information includes latitude and longitude information as well as node information.

When the communication with the external server 100 is on-line, the navigation control unit 4 requests the external server 100 to acquire the latest map data and generate a travel guidance route. That is, the navigation control unit 4 recognizes the position of the vehicle detected by the GPS 21 as the position information of the vehicle. It transmits the latest map data acquisition request and route generation request to the external server 100 . The navigation control unit 4 downloads the latest map data (server map data) and guidance information through communication with the external server 100 and stores the latest map data in the map data storage section 3 . Then, the navigation control unit 4 acquires the stored map data by requesting the map data storage unit 3 for the stored map data centered on the vehicle position, and based on the vehicle position information, the stored map data and the guidance information. It outputs guidance route information to the HMI device 6 . When communication with the external server 100 is off-line, the navigation control unit 4 integrates input information from the in-vehicle sensor 2 and the map data storage unit 3, and generates a travel guidance route from the departure point to the destination. have a function. The navigation control unit 4 then outputs guidance route information to the HMI device 6 .

The touch panel 5 is data input means provided on the surface of the HMI device 6 . A user of the navigation device 1 operates the touch panel 5 to input the destination of the vehicle to the navigation control unit 4 .

The HMI device 6 is a device that provides information such as where the vehicle is moving on the map during route guidance. "HMI" is an abbreviation for "Human Machine Interface". Examples of the HMI device 6 include a HUD (Head-UP Display), a meter display, and an in-vehicle monitor in combination of one or more.

The external server 100 is a server in a cloud environment, and has a function of returning external map data (server map data) including guidance information to the navigation device 1 in response to a request from the navigation device 1 . The external server 100 has an external data communication device 101 , a latest map data storage section 102 and a route generation section 103 .

The external data communication device 101 performs wireless communication with the vehicle-mounted data communication device 24 via the transmission/reception antennas 24a and 101a, receives information and requests from the navigation device 1, and displays an external map according to the request. Data is sent to the navigation device 1 .

The latest map data storage unit 102 is composed of an external server memory that stores the latest map data in which latitude/longitude and map information are associated with each other in the same manner as the stored map data. The latest map data storage unit 102 has road information associated with each point in the same manner as the stored map data, and includes background map information and node information. The latest map data storage unit 102 also stores traffic information such as congestion information and travel regulation information.

Here, the "latest map data" is the latest map data updated up to now. Among the latest map data, the map data from the departure point to the destination of the travel guidance route is called "external map data". The external map data also includes map data to be referred to when traveling the travel guidance route. Note that the travel guide route is generated upon request from the navigation control unit 4 . The map data of each section obtained by dividing the external map data into section Z(n) for each guidance point P(n) on the travel guidance route is referred to as "section map data". "Guidance location P(n)" is information attached to a node, and indicates that the node is attached with separate guidance information. Therefore, a node attached with the guidance point P(n) is in a state in which no guidance information is actually attached. A guide point P(n) has one node attached with the guide point P(n) or a node group (portion) in which a plurality of nodes attached with the guide point P(n) are continuous. In the case of a node group, it is handled as one guide point P(n). It should be noted that nodes at the departure point and the destination are attached with guidance points P(n). The section map data is composed of guide information as first information, background map information as second information, node information, and link information connecting each node. Among the information constituting the section map data, the guidance information has a smaller data amount than the background map information.

The route generation unit 103 integrates the vehicle position information, destination information, map data acquisition request, and route generation request from the navigation control unit 4 with the latest map data stored in the latest map data storage unit 102, etc., and provides travel guidance. It has the function of generating routes. The route generation unit 103 transmits the “node information and link information” from the departure point to the destination of the travel guidance route to the navigation control unit 4 through communication. It is assumed that the node information to be transmitted is attached with the guide point P(n) based on the generated travel guide route, but is not attached with the guide information. Furthermore, the route generation unit 103 divides the section map data into two parts, ie, “guidance information” and “background map information”, and transmits them to the navigation control unit 4 . Information on the generated travel guidance route is reflected in the guidance information. It is assumed that the latest map data acquisition request also includes a request to separately transmit "node information and link information" and section map data "guidance information" and "background map information". It is also assumed that the latest map data acquisition request also includes a request to attach the guide point P(n) to the "node information".

The main configuration of the navigation control unit 4 will be described with reference to FIGS. 2 and 3. FIG.

The navigation control unit 4 selects "node information and link information" from the departure point to the destination of the travel guidance route among the latest map data prior to "guidance information" and "background map information" of the section map data. to download. When storing the downloaded node information, the navigation control unit 4, of the stored map data already stored in the map data storage unit 3, stores the stored map data of the area corresponding to the downloaded departure point to the destination, Replace with downloaded information. Furthermore, at the time of this storage, the link information is not stored in the map data storage section 3, but is held by the navigation control unit 4. FIG.

The navigation control unit 4 uses the guidance point P(n) as a reference, and when the user's own vehicle arrives at the guidance point P(n), the navigation control unit 4 updates the section map data "guidance information" and " Download background map information. The navigation control unit 4 holds the downloaded guidance information and stores the downloaded background map information. When storing the background map information, among the stored map data already stored in the map data storage unit 3, the stored map data of the section corresponding to the downloaded predetermined section Z(n) is rewritten with the downloaded background map information. .

The navigation control unit 4 has a map recording device 40, a display route generation section 4e, a new/old comparison section 4f, and an output section 4g. The map recording device 40 has a time prediction section 4a, a time comparison section 4b, a first download section 4c, and a second download section 4d.

Vehicle position information, vehicle speed information, traffic congestion information, and the like are input to the time prediction unit 4a. When the time prediction unit 4a downloads the section map data of the predetermined section Z(n) divided for each guidance point P(n), when the own vehicle arrives at the guidance point P(n), the required travel time T(n ) and the required download time t(n). The required travel time T(n) is from the guide point P(n) indicating the start point of the predetermined section Z(n) to be downloaded to the next guide point P(n+1) indicating the end point. , is the time required for the vehicle to move in a predetermined section Z(n). When predicting the required travel time T(n), the vehicle speed of the own vehicle, the distance of the predetermined section Z(n), traffic information, and the characteristics of the predetermined section Z(n) are taken into consideration. The vehicle speed of the own vehicle is, for example, the legal speed of the predetermined section Z(n). The characteristics of the predetermined section Z(n) are the running load resistance (gradient and rough road) and road shape (curved road). When the guidance point P(n) or the next guidance point P(n+1) is a node group, the node located in front of the traveling direction of the vehicle is set as the starting point or the ending point. The required download time t(n) is the time required to download the section map data of the predetermined section Z(n). When estimating the required download time t(n), the communication speeds of the vehicle-mounted data communication device 24 and the external data communication device 101 in the predetermined section Z(n) are taken into consideration. The time prediction unit 4a outputs the predicted travel time T(n) and download time t(n) to the time comparison unit 4b.

Here, for example, as shown in FIG. 3, when downloading the first section map data of the first first section Z1, the first required travel time T1 and the first required download time t1 are predicted. The first section Z1 is a section from the initial guidance point P0 as the departure point to the next first guidance point P1. First, the first required travel time T1 is the time required for the vehicle to move in the first section Z1 from the initial guidance point P0 indicating the start point of the first section Z1 to the next first guidance point P1 indicating the end point. Become. Next, the first required download time t1 is the time required to download the first section map data.

The required travel time T(n) and the required download time t(n) are input to the time comparator 4b. The time comparison unit 4b compares the required travel time T(n) with the required download time t(n), and determines that the required travel time T(n) is less than or equal to the required download time t(n) (T(n)≤t( n))). For example, as shown in FIG. 3, when the first required download time t1 is time t11, the time comparator 4b determines that the first required travel time T1 is less than or equal to time t11 (T1≦t11). On the other hand, when the first required download time t1 is time t12, the time comparator 4b determines that the first required travel time T1 is longer than time t12 (T1>t12). The time comparison unit 4b outputs the time comparison result to the first download unit 4c, the second download unit 4d, and the new/old comparison unit 4f.

A time comparison result is input to the first download unit 4c. When the time comparison result is input, the first download unit 4c generates route guidance information of the next guidance point P(n+1) among the section map data of the predetermined section Z(n) through communication regardless of the result. Download from section 103 . Downloading of the guidance information is started when the vehicle arrives at the guidance point P(n) based on the guidance point P(n). For example, as shown in FIG. 3, with the initial guidance point P0 as a reference, when the vehicle arrives at the initial guidance point P0, downloading of the first guidance information of the first section map data is started. Specifically, when the vehicle position is the initial guidance point P0, the first guidance information for the next first guidance point P1 is downloaded from the route generation unit 103 by communication. When "T(n)>t(n)" holds, the first download unit 4c outputs a download end signal to the second download unit 4d when the download is completed.

The time comparison result and the download end signal are input to the second download unit 4d. The second download unit 4d does not download the background map information of the section map data of the predetermined section Z(n) when the time comparison result is "T(n)≤t(n)". For example, as shown in FIG. 3, the second download unit 4d does not download the first background map information of the first section map data when the time comparison result is "T1≤t11". On the other hand, if the time comparison result is "T(n)>t(n)", the second download unit 4d downloads the predetermined interval Z(n) through communication after the download end signal is input, that is, after the download of the guidance information is completed. of the section map data, the background map information is downloaded from the route generation unit 103 . For example, as shown in FIG. 3, when the time comparison result is "T1>t12", the second download unit 4d downloads the first background map information to the route generation unit 103 through communication after the download of the first guidance information is finished. Download from

The display route generation unit 4e reads the downloaded node information and the background map information from the map data stored in the map data storage unit 3. FIG. The read range of node information is the range displayed on the HMI device 6 . As the node information, the node information after rewriting by downloading is read out of the stored map data. The reading range of the background map information is the same range as the node information, and is the range to be referred to when traveling the travel guidance route. As the background map information, if the background map information is not downloaded or if the download of the background map information is not completed, the background map information before rewriting is read out of the stored map data. On the other hand, as the background map information, after the background map information has been downloaded, the rewritten background map information of the stored map data is read.

The display route generation unit 4e generates guidance route information based on the background map information, the node information and the link information, or these three pieces of information and the guidance information, and outputs the guidance route information to the output unit 4g. That is, when the display route generation unit 4e generates the guide route information based on the background map information, the node information, and the link information, the display route generation unit 4e combines the two pieces of information according to the longitude and latitude contained in the node information and the background map information, Generate guidance route information to be displayed on the HMI device 6 . On the other hand, when the display route generation unit 4e generates the guidance route information based on the three pieces of information and the guidance information, the two pieces of information are matched by the latitude and longitude information included in the node information and the guidance information. Further, the node information combined with the guidance information and the longitude and latitude contained in the background map information are combined to generate guidance route information to be displayed on the HMI device 6 . In addition, the current position of the vehicle and link information are added to both guidance route information based on the position information of the vehicle.

A time comparison result is input to the new/old comparison unit 4f. When the time comparison result is "T(n)≤t(n)", the new/old comparison unit 4f corresponds to the node information downloaded through communication with the external server 100 and the guidance information read from the map data storage unit 3. Compare the new and old information of the stored map data and the map data version. Specifically, the new/old comparison unit 4f reads the node information after rewriting by downloading and the background map information before rewriting corresponding to the guidance information of the next guidance point P(n+1) from the stored map data. , compare the old and new information of the map data version of the two information. The comparison of the new and old information is performed based on the version information of each information. The new/old comparison unit 4f determines whether or not the map data versions of the two pieces of information match, and outputs the comparison result of the map data versions to the output unit 4g. Note that the new/old comparison unit 4f does not compare the new/old information of the map data version when the time comparison result is "T(n)>t(n)".

The guidance route information and the new/old comparison result are input to the output unit 4g. The output unit 4g converts the guidance route information into a display signal when the new and old comparison results match, and converts the guidance route information and the old information of the map data version into a display signal when the new and old comparison results do not match. The output unit 4g outputs either display signal to the HMI device 6. FIG.

Next, the operation of the first embodiment will be described by dividing it into "external server processing operation", "route guidance processing operation", "download processing operation", and "new/old notification processing operation".

First, based on FIG. 4, the operation of the external server processing will be described. The processing in FIG. 4 is executed by the external server 100 and the route generation unit 103. FIG. When the external server 100 receives the vehicle position information, the destination information, the map data acquisition request, and the route generation request from the navigation control unit 4 through communication, the process starts.

When started, the process proceeds to S11, S13 and S15 in order. First, the route generator 103 generates a travel guidance route (S11). Next, the route generator 103 transmits "node information and link information" from the departure point to the destination of the travel guidance route to the navigation control unit 4 by communication (S13). Subsequently, the route generation unit 103 determines whether or not there is a request to acquire the guidance information of the next guidance point P(n+1) transmitted from the first download unit 4c (S15). Here, whether or not there is an acquisition request is determined by the path generation unit 103 based on the input from the first download unit 4c. Then, while the judgment of S15 is negative, S15 is repeated, and when the judgment of S15 is affirmative, the process proceeds to S17 and S19.

Next, the route generation unit 103 starts transmitting the guidance information of the next guidance point P(n+1) to the first download unit 4c by communication (S17). Next, the route generation unit 103 determines whether or not the transmission of the guidance information to the first download unit 4c has ended (S19). Here, whether or not the transmission is completed is determined by the route generating section 103 from the state of the external data communication device 101 . For a while, the download is in progress, so the determination in S19 is negative, so S19 is repeated.

Then, when the determination in S19 is affirmative, the process proceeds to S21. The route generation unit 103 determines whether or not there is a request to acquire the background map information of the predetermined section Z(n) transmitted from the second download unit 4d (S21). Here, the determination of whether or not there is an acquisition request is the same as in S15, so the description is omitted. If the determination in S21 is affirmative, the process proceeds to S23 and S25. On the other hand, if the determination in S21 is negative, the process proceeds to S27.

Next, when the determination in S21 is affirmative, the route generation unit 103 starts transmitting the background map information of the predetermined section Z(n) to the second download unit 4d through communication (S23). Next, the route generation unit 103 determines whether or not the transmission of the background map information to the second download unit 4d has ended (S25). Here, the determination as to whether or not the transmission has ended is the same as in S19, so the description thereof is omitted. For a while, the download is in progress, so the determination in S25 is negative, so S25 is repeated. Then, when the determination in S25 is affirmative, the process proceeds to S27.

Next, the route generator 103 determines whether or not the next guidance point P(n+1) is the destination (S27). Here, whether or not the destination is the destination is determined based on the next guide point P(n+1) and the latitude and longitude of the destination information. For a while, it is determined that the next guidance point P(n+1) is not the destination, so the determination in S27 is denied. If the determination in S27 is negative, the process returns to S15, and the flow from S15 to S27 is repeated. Then, if the determination in S27 is affirmative, the process proceeds to the end.

In S17 and S23, the external map data from the departure point to the destination is divided into section map data for each section for each guidance point P(n) on the travel guidance route and transmitted. For example, if the external map data from the departure point to the destination is transmitted all at once, the transmission will be useless due to deviation of the vehicle's travel guidance route. Therefore, section map data is transmitted. As a result, even if the route is deviated on the way to the destination due to detours or traffic jam avoidance, it is possible to prevent the transmission of the section map data from becoming useless communication.

Furthermore, in S17 and S23, the section map data is divided into two parts, the guide information and the background map information, and transmitted. For example, if the section map data is transmitted without being divided, depending on the communication environment, the section map data may not be downloaded in time, making it impossible to provide route guidance to passengers. For this reason, the section map data is divided into two and transmitted, and furthermore, since the amount of data of the guidance information is smaller than that of the background map information, priority is given to downloading the guidance information necessary for route guidance. As a result, even if background map information cannot be downloaded in time, it is possible to provide route guidance to passengers using the minimum required node information and guidance information for route guidance, as well as background map information read from stored map data. is.

Next, based on FIG. 5, the operation of route guidance processing will be described. The processing in FIG. 5 is executed by the navigation control unit 4 and the display route generation section 4e. When the ignition switch of the own vehicle is in the ON state, the navigation control unit 4 downloads "node information and link information" from the departure point to the destination of the travel guidance route from the route generation unit 103 by communication. , to start. When started, the process proceeds in order of S31, S33, S35 and END.

First, node information and background map information are read from the map data storage unit 3 by the display route generation unit 4e (S31). Next, the displayed route generating unit 4e generates guidance route information based on at least the background map information, the node information and the link information (S33). Subsequently, the generated guide route information is output to the output unit 4g by the display route generation unit 4e (S35). Since the guidance route information is generated in this manner, the guidance route information can be generated even when the background map information is not downloaded or before the background map information is completely downloaded.

Then, based on FIG. 6, the action of the download processing will be described. The process of FIG. 6 is executed by the navigation control unit 4, the time prediction section 4a, the time comparison section 4b, the first download section 4c, and the second download section 4d. The navigation control unit 4 downloads "node information and link information" from the departure point to the destination of the travel guidance route from the route generation unit 103 by communication, and starts when the vehicle position is the departure point. .

When started, the process proceeds to S41, S43 and S45 in order. First, the time prediction unit 4a predicts the required travel time T(n) of the predetermined section Z(n) by calculation (S41). In S41, when predicting the travel time T(n), the vehicle speed of the host vehicle and the like are taken into consideration. Therefore, when the required travel time T(n) is predicted, taking these pieces of information into account is more accurate than considering only the vehicle speed and the distance of the predetermined section Z(n). ) can be predicted.

Next, the time prediction unit 4a calculates and predicts the required download time t(n) of the section map data for the predetermined section Z(n) (S43). Subsequently, the time comparison unit 4b determines whether or not the required travel time T(n) is equal to or less than the required download time t(n) (T(n)≤t(n)) (S45).

If the determination in S45 is affirmative, the process proceeds to S47 and S49. The first download unit 4c starts downloading the guide information of the next guide point P(n+1) (S47). Here, when the download of the guidance information is started, the first download section 4c transmits a guidance information acquisition request to the route generation section 103 by communication. Next, the first download unit 4c determines whether or not the download of the guide information has ended (S49). Here, whether or not the download has been completed is determined from the state of the in-vehicle data communication device 24 by the first download section 4c. For a while, the download is in progress, so the determination in S49 is negative, so S49 is repeated. Then, when the determination in S49 is affirmative, the process proceeds to S61.

On the other hand, if the determination in S45 is negative, the process proceeds to S51 and S53 in order. Since S51 and S53 are the same as S47 and S49, their explanation is omitted. However, if the determination in S53 is affirmative, the process proceeds to S55 and S57. Further, when the determination in S53 is affirmative, the first download section 4c outputs a download end signal to the second download section 4d. Next, the download of the background map information is started by the second download unit 4d (S55). Here, when the download of the background map information is started, the second download unit 4d transmits a request to acquire the background map information to the route generation unit 103 through communication. Next, the second download unit 4d determines whether or not the download of the background map information is completed (S57). Here, whether or not the download has been completed is determined from the state of the vehicle-mounted data communication device 24 by the second download unit 4d. For a while, the download is in progress, so the determination in S57 is negative, so S57 is repeated. Then, when the determination in S57 is affirmative, the process proceeds to S61.

By proceeding to S51, S53, S55 and S57 in this order, the background map information is downloaded after the download of the guidance information is completed. For example, there is a possibility that the required travel time T(n) will be earlier than predicted depending on the traffic congestion, or that the required download time t(n) will be longer than predicted depending on the communication environment. In this case, when the guidance information is downloaded after the background map information has been downloaded, the guidance information used for route guidance may not be downloaded in time, and the route guidance may not be performed. Therefore, the guide information is downloaded before the background map information is downloaded. As a result, it is possible to reliably download the guidance information necessary for route guidance in time for the next guidance point P(n+1), and to reliably perform route guidance.

Then, the navigation control unit 4 determines whether or not the next guidance point P(n+1) is the destination (S61). Here, whether or not the destination is the destination is determined based on the next guide point P(n+1) and the latitude and longitude of the destination information. Since it is determined that the next guidance point P(n+1) is not the destination for a while after the departure point, the determination in S61 is denied.

If the determination in S61 is negative, the process proceeds to S63. The navigation control unit 4 determines whether or not the vehicle has arrived at the next guidance point P(n+1) (S63). Here, whether or not the vehicle has arrived is determined based on the next guide location P(n+1) and the latitude and longitude of the vehicle position information (S63). Until the next guide point P(n+1) is reached, the determination in S63 is negative, so S63 is repeated. Then, when the determination in S63 is affirmative, the process proceeds to S65. Then, the navigation control unit 4 outputs the current predetermined section Z(n), the guidance point P(n) indicating the start point of the current predetermined section Z(n), and the next guidance point P(n+1) indicating the end point. , are updated (S65). That is, the current predetermined section Z(n) is updated to the next predetermined section Z(n+1). Furthermore, the guidance point P(n) indicating the starting point of the current predetermined section Z(n) is updated to the guidance point P(n+1) indicating the starting point of the next predetermined section Z(n+1). Furthermore, the next guidance point P(n+1) indicating the end point of the current predetermined section Z(n) is updated to the next guidance point P(n+2) indicating the end point of the next predetermined section Z(n+1). After completing the process of S65, the process returns to S41, and the flow from S41 to S65 is repeated. Then, when the determination in S61 is affirmative, the process proceeds to the end.

Next, based on FIG. 7, the download operation of the flow chart of FIG. 6 will be described.

First, since the vehicle position is the initial guidance point P0 as the departure point, the first guidance information of the first guidance point P1 or the first guidance information of the first section Z1 from the initial guidance point P0 to the next first guidance point P1. Section map data is downloaded. At this time, the first travel time T1 and the first download time t1 are predicted. Here, since it is determined that the first travel time T1 is equal to or shorter than the first download time t1, only the first guide information of the first section map data is downloaded. Therefore, the first background map information of the first section map data is not downloaded. The required time required for downloading only the first guide information is indicated by "t13".

Next, when the vehicle position reaches the first guidance point P1, the first section Z1, the initial guidance point P0, and the first guidance point P1 become the second section Z2, the first guidance point P1, and the second guidance point P2. , respectively. Then, when the vehicle position reaches the first guide point P1, the second guide information of the second guide point P2 or the second guidance information of the second section Z2 from the first guide point P1 to the next second guide point P2. Section map data is downloaded. At this time, a second travel time T2 and a second download time t2 are predicted. Here, since it is determined that the second travel time T2 is longer than the second download time t2, the download of the second section map data is executed. When downloading the second section map data, the second background map information is downloaded after the download of the second guide information is completed.

Subsequently, when the vehicle position reaches the second guide point P2, the second section Z2, the first guide point P1, and the second guide point P2 are changed to the third section Z3, the second guide point P2, and the third guide point P3. , respectively. Then, when the vehicle position reaches the second guide point P2, the third guide information of the third guide point P3 or the third guidance information of the third section Z3 from the second guide point P2 to the next third guide point P3. Section map data is downloaded. At this time, a third travel time T3 and a third download time t3 are predicted. Here, since it is determined that the third travel time T3 is longer than the third download time t3, the download of the third section map data is executed. When downloading the third section map data, the third background map information is downloaded after the download of the third guidance information is completed.

Then, when the vehicle arrives at the guidance point P(n) of the predetermined section Z(n), the guidance information of the next guidance point P(n+1) or the section map data of the predetermined section Z(n) is downloaded. . At this time, as described above, the required travel time T(n) and the required download time t(n) are predicted. The predicted required travel time T(n) and the required download time t(n) are compared, and based on the time comparison result, guidance information for the next guide point P(n+1) or section map data for the predetermined section Z(n) is obtained. Downloaded. If it is determined that the next guide point P(n+1) is the destination after either download, the flow chart of FIG. 6 ends.

In this way, since the guidance information is downloaded regardless of the time comparison result, appropriate route guidance to the user is performed at the next guidance point P(n+1) regardless of whether or not the background map information is downloaded. . In addition, since the data volume of the guidance information is smaller than the data volume of the background map information, the guidance information can be reliably downloaded within the required movement time T(n).

Then, when the time comparison result is "T(n)≤t(n)", the background map information is not downloaded. For example, in FIG. 7, even if the first background map information is downloaded, the download ends after the vehicle passes through the first section Z1. Then, even if the first background map information is downloaded, the first background map information is useless because it is unnecessary for route guidance. In addition, the download of the first background map information ends at unnecessary timing. It should be noted that if the download of the first background map information is costly, the additional cost will be incurred. On the other hand, in the first embodiment, whether or not to download the background map information is determined according to the time comparison result. That is, when the time comparison result is "T(n)≤t(n)", the background map information is not downloaded, so that the background map information of the section map data is not wasted. Even in this case, since the guidance information is downloaded, appropriate route guidance to the user is performed. Therefore, wasteful downloading of background map information is eliminated, and appropriate route guidance to the user is provided.

On the other hand, when the time comparison result is "T(n)>t(n)", background map information is downloaded. For example, in FIG. 7, when the second background map information is downloaded, the download ends before the vehicle passes through the second section Z2. Then, even if the second background map information is downloaded, the second background map information will not be wasted because it is necessary for route guidance. As a result, the background map information can be used for the route guidance of the second section Z2 at the necessary timing after the background map information is downloaded, so detailed route guidance can be performed. Since the external map data is not downloaded all at once, route guidance can be provided using the latest background map information without waiting for the completion of downloading the external map data.

Furthermore, by selecting the information to be downloaded based on the time comparison results, it is possible to eliminate wasteful downloads while maintaining the quality of route guidance, and to enable route guidance based on the latest map data.

Furthermore, with reference to the guide point P(n), when the vehicle arrives at the guide point P(n), time prediction and time comparison control is performed, and guidance information or section map data of the predetermined section Z(n) is displayed. download is controlled. For example, in FIG. 7, when the own vehicle arrives at each guide point P0, P1, P2, time prediction, time comparison, and download are controlled. Therefore, it is possible to control time prediction, time comparison, and download by dividing it into each predetermined section Z(n).

Then, based on FIG. 8, the action of the new/old notification processing will be described. The processing in FIG. 7 is executed by the navigation control unit 4, the display route generation section 4e, the new/old comparison section 4f, and the output section 4g. If the determination in S45 of FIG. 6 is affirmative, the process is started.

When started, the process proceeds to S71, S73 and S75 in order. That is, when the node information is downloaded, the node information of the stored map data is rewritten (S71). Therefore, route guidance is executed from the departure point. Next, the new/old comparison unit 4f compares the node information of the predetermined section Z(n) after rewriting by downloading and the guidance information of the next guidance point P(n+1) of the predetermined section Z(n) from the stored map data. The corresponding background map information before rewriting is read (S73).

Subsequently, when the time comparison result is “T(n)≦t(n)”, the new/old comparison unit 4f determines the map data version of the node information after rewriting, the map data version of the background map information before rewriting, are compared, and it is determined whether or not the map data versions match (S75). Here, the determination of whether or not the map data versions match will be described. For example, when the map data version of the node information after rewriting is "2" and the map data version of the background map information before rewriting is "1", the new/old comparison unit 4f determines that the map data of the background map information is higher than that of the node information. The data version is determined to be "mismatched (old)". Note that the map data version of the background map information before rewriting does not always match the map data version of the node information after rewriting (old). That is, if there is no change in the downloaded node information, the new and old information of the map data versions of the two pieces of information may match. In this case, the new/old comparison unit 4f determines that the map data version of the node information after rewriting and the map data version of the background map information before rewriting "match (new)".

As described above, in S75, when the time comparison result is "T(n)≤t(n)" after the node information has been downloaded, the new and old information of the map data versions of the two pieces of information are compared. , a comparison result of the map data versions of the two pieces of information is obtained.

Then, when the determination in S75 is affirmative, the process proceeds to S81, S83 and END in this order. The guidance route information is input to the output unit 4g by the display route generation unit 4e (S81). Next, the output unit 4g converts the guidance route information into a display signal and outputs the display signal to the HMI device 6 (S83). Information on new and old data versions is not displayed, only guidance route information is displayed.

On the other hand, if the determination in S75 is negative, the process proceeds to S85, S87 and END in that order. The guidance route information is input to the output unit 4g by the display route generation unit 4e (S85). The output unit 4g converts the guidance route information and the old information of the map data version into a display signal, and outputs the display signal to the HMI device 6 (S87). On the HMI device 6, for example, as shown in FIG. 10, in addition to the guide route information, the letters "Old" are displayed on the upper left as old information.

The reason for displaying the old information in this way is as follows. That is, a travel guidance route is generated from the latest map data of the external server 100, and node information and guidance information are downloaded prior to background map information. Next, when guidance route information to be displayed on the HMI device 6 is generated from the rewritten node information and the pre-rewritten background map information, a contradiction may occur between the two pieces of information. If contradiction occurs in the guidance route information during route guidance, the user does not know whether the background map information is old or not, and does not know whether the route guidance can be referred to. Then, during the route guidance, the user becomes confused about the route guidance. Therefore, old information is displayed. That is, the user of the own vehicle can recognize that the background map information before rewriting is older than the node information after rewriting. Therefore, during the route guidance, the user of the own vehicle can recognize the new and old information of the map data.

Furthermore, it can be seen that it is better not to refer to the background map information when traveling straight ahead in FIG. For example, when the vehicle is traveling straight in FIG. 9 and the old display is displayed as in FIG. 10, it can be understood that the background map information may be referred to. In this way, by displaying the old information in addition to the guidance route information, it is possible to suppress the user's confusion regarding the route guidance during the route guidance. Furthermore, by displaying "old" rather than displaying "new", the user can be notified in advance that the background map information is older than the node information during route guidance (perceive). can be done. As a result, the user can be alerted during route guidance.

As described above, the map data download method and the map recording device of the first embodiment have the following effects.

(1) Route based on external server 100 storing server map data (latest map data), user map data (stored map data) stored in memory (map data storage unit 3), and driving guidance route This is a method of downloading map data through communication with a user controller (navigation control unit 4) that executes guidance. In this map data download method, the user controller (navigation control unit 4) communicates with the external server 100 to download the server map data (external map data) from the departure point to the destination for guidance on the travel guidance route. When dividing and downloading the section map data of each section Z(n) for each location P(n), the following is performed. A required movement time T(n) required to move a predetermined section Z(n) from the guidance point P(n) to the next guidance point P(n+1) is predicted (S41). A required download time t(n) required to download the section map data of the predetermined section Z(n) is predicted (S43). The required travel time T(n) and the required download time t(n) are compared (S45). Of the first information (guidance information) and the second information (background map information) constituting the section map data, the first information (guidance information) is downloaded (S47 and S49 and S51 and S53). The first information (guidance information) is information used for route guidance at the next guidance point P(n+1) in the predetermined section Z(n). When it is determined from the time comparison result that the required travel time T(n) is equal to or less than the required download time t(n) (T(n)≤t(n)), the second information (background map information) is not downloaded. (“YES” in S45). On the other hand, when it is determined from the time comparison result that the required travel time T(n) is longer than the required download time t(n) (T(n)>t(n)), the second information (background map information) is Download (“NO” in S45, S55 and S57).

In this way, by downloading the first information (guidance information) regardless of the time comparison result, appropriate route guidance to the user is performed. Furthermore, when the time comparison result is "T(n)≤t(n)", the second information (background map information) is not downloaded, thereby eliminating unnecessary downloading of the map data (background map information). be. In other words, it prevents map data download from becoming unnecessary communication. Therefore, it is possible to provide a method of downloading map data that eliminates wasteful downloading of map data and provides appropriate route guidance to the user. In addition, when the time comparison result is "T(n)>t(n)", even if the second information (background map information) is downloaded, the second information (background map information) is not necessary for route guidance. It will not be wasted. Therefore, after the second information (background map information) is downloaded, it can be used for route guidance for the predetermined section Z(n), so detailed route guidance can be provided.

(2) The second information is background map information.

Therefore, when the time comparison result is "T(n)≤t(n)", by not downloading the background map information that is not directly related to the guidance, accurate guidance can be continued while the background map information is not downloaded. Such communication traffic can be reduced.

(3) The first information has a smaller data amount than the second information.

Therefore, it is possible to reliably download the guidance information within the required travel time T(n).

(4) The user controller (navigation control unit 4) uses the guidance point P(n) as a reference, and when the user (own vehicle) arrives at the guidance point P(n) (START and "YES" in S63), 1 information (guidance information) or section map data is downloaded (S47-S57).

Therefore, the download of the first information (guidance information) or the section map data can be controlled by dividing it into each predetermined section Z(n).

(5) When the user controller (navigation control unit 4) downloads both the first information (guidance information) and the second information (background map information) according to the time comparison result (“NO” in S45), the first After the information (guidance information) has been downloaded ("YES" in S53), the second information (background map information) is downloaded (S55 and S57).

Therefore, it is possible to reliably download the guidance information necessary for route guidance in time for the next guidance point P(n+1), and to reliably perform route guidance.

(6) The memory (map data storage section 3) and the user controller (navigation control unit 4) are mounted on the vehicle. When the user controller (navigation control unit 4) predicts the required travel time T(n), the vehicle speed, the distance of the predetermined section Z(n), traffic congestion information, and the characteristics of the predetermined section Z(n) are used. Consider (S41).

Therefore, when the required travel time T(n) is predicted, taking these pieces of information into account is more accurate than considering only the vehicle speed and the distance of the predetermined section Z(n). can be predicted.

(7) A memory (map data storage unit 3), a user controller (navigation control unit 4), and a notification device (HMI device 6) are mounted on the vehicle. When the user controller (navigation control unit 4) communicates with the external server 100 to download server map data (latest map data), it performs the following. The node information is downloaded prior to downloading the first information (guidance information). When only the first information (guidance information) is downloaded as a result of the time comparison ("YES" in S45), the map data version of the downloaded node information and the first information (guidance information) read from the memory (map data storage unit 3) (S75). If the map data versions match ("YES" in S75) as a result of comparing the new and old map data versions, the new and old information of the map data versions is not output to the notification device (HMI device 6) (S83). If the map data versions do not match as a result of comparing the old and new versions of the map data ("NO" in S75), the old information of the map data version is output to the notification device (HMI device 6) (S87).

Thus, when the map data versions do not match, the old information of the map data is displayed on the notification device (HMI device 6) by outputting the old information to the notification device (HMI device 6). Therefore, during route guidance, the user can be notified in advance that the background map information is older than the node information. Therefore, it is possible to alert the user during route guidance.

(8) Route guidance is executed based on the external server 100 storing server map data (latest map data) and user map data (stored map data) stored in the memory (map data storage unit 3). A map recording device 40 in communication with a user controller (navigation control unit 4). In this map recording device 40, the user controller (navigation control unit 4) communicates with the external server 100 to store the server map data (external map data) from the departure point to the destination as guidance points on the travel guidance route. Section map data for each section Z(n) for each P(n) is divided and downloaded. At this time, the user controller (navigation control unit 4) has a time prediction section 4a, a time comparison section 4b, a first download section 4c, and a second download section 4d. The time prediction unit 4a predicts the required movement time T(n) required to move a predetermined section Z(n) from the guidance point P(n) to the next guidance point P(n+1) (S41), and A required download time t(n) required for downloading the section map data of Z(n) is predicted (S43). The time comparison unit 4b compares the required travel time T(n) and the required download time t(n) (S45). The first download unit 4c downloads the first information (guidance information) out of the first information (guidance information) and the second information (background map information) constituting the section map data regardless of the time comparison result (S45). Download (S47 and S49 and S51 and S53). The first information (guidance information) is information used for route guidance at the next guidance point P(n+1) in the predetermined section Z(n). When the second download unit 4d determines from the time comparison result that the travel time T(n) is equal to or less than the download time t(n) (T(n)≤t(n)), the second information ( background map information) is not downloaded ("YES" in S45). On the other hand, when it is determined from the time comparison result that the required travel time T(n) is longer than the required download time t(n) (T(n)>t(n)), the second information (background map information) is Download (“NO” in S45, S55 and S57).

In this way, by downloading the first information (guidance information) regardless of the time comparison result, appropriate route guidance to the user is performed. Furthermore, when the time comparison result is "T(n)≤t(n)", the second information (background map information) is not downloaded, thereby eliminating wasteful downloading of map data. Therefore, it is possible to provide the map recording device 40 that eliminates unnecessary downloading of map data and provides appropriate route guidance to the user. In addition, when the time comparison result is "T(n)>t(n)", even if the second information (background map information) is downloaded, the second information (background map information) is not necessary for route guidance. It will not be wasted. Therefore, after the second information (background map information) is downloaded, it can be used for route guidance for the predetermined section Z(n), so detailed route guidance can be provided.

A second embodiment is an example in which the section map data is continuously downloaded from the departure point as the departure point reference.

The map data download method and the map recording device in the second embodiment are applied in the same manner as in the first embodiment. Since the overall system configuration of the second embodiment is the same as that of the first embodiment, the description is omitted.

Based on FIG. 11, the essential configuration of the navigation control unit of the second embodiment will be described.

The navigation control unit 4' continuously downloads the "guidance information" and "background map information" of the section map data among the latest map data (server map data) from the departure point as the departure point reference. Other descriptions are the same as those of the navigation control unit 4 of the first embodiment, so are omitted.

The navigation control unit 4' has a map recording device 40', a displayed route generation section 4e, a new/old comparison section 4f', and an output section 4g. The map recording device 40' has a time prediction section 4a', a time comparison section 4b', a first download section 4c', and a second download section 4d'. Note that the display path generation unit 4e and the output unit 4g are the same as those in the first embodiment, so description thereof will be omitted.

Vehicle position information, vehicle speed information, traffic congestion information, and the like are input to the time prediction unit 4a'. When downloading the section map data of the predetermined section Z(n) divided for each guidance point P(n), the time prediction unit 4a' downloads the predetermined section Z(n -1) After completing the download, predict the total required travel time T'(n) and the total required download time t'(n). The total required travel time T'(n) is the time required for the vehicle to travel from the departure point to the next guidance point P(n+1) in the predetermined section Z(n). When estimating the total required travel time T'(n), the vehicle speed of the own vehicle and the like are taken into account, as in the first embodiment. If the guidance point P(n) or the next guidance point P(n+1) is a node group, the node located in front of the vehicle in the traveling direction is set as the starting point or the ending point, as in the first embodiment. The total required download time t'(n) is the time required for continuous download time from the departure point, the time required for downloading the section map data of the predetermined section Z(n) (required download time t(n)), is the total time of When estimating the total required download time t'(n), the communication speed and the like are taken into account as in the first embodiment. The time prediction unit 4a' outputs the predicted total travel time T'(n) and total download time t'(n) to the time comparison unit 4b'. The time prediction unit 4a' predicts the required travel time T(n) as the total required travel time T'(n), and predicts the required download time t(n) as the total required download time t'(n). .

Here, for example, as shown in FIG. 11, when downloading the first section map data, the process is the same as in the first embodiment, so the description is omitted. Next, when only the first guidance information of the first section map data is downloaded in the first section Z1, and the second guidance information or the second section map data of the second section Z2 is downloaded, the second travel total required Predict time T2' and second download total required time t2'. The second section Z2 is a section from the first guide point P1 to the next second guide point P2. First, the second total required travel time T2' is the time required for the vehicle to travel from the departure point to the next second guide point P2. That is, the second total travel time T2′ is the total time of the first travel time T1 (=first travel total time T1′) and the second travel time T2 required for travel in the second zone Z2. becomes. Next, the second download total required time t2′ is the time t13 required for the continuous download time from the starting point, the initial guide point P0, and the second download required to download the second section map data of the second section Z2. It is the total time of the required time t2.

The total required travel time T'(n) and the total required download time t'(n) are input to the time comparator 4b'. The time comparison unit 4b' compares the total required travel time T'(n) with the total required download time t', and the total required travel time T'(n) is less than or equal to the total required download time t'(n) (T Determine whether '(n)≤t'(n)). For example, as shown in FIG. 11, when the second total required download time t2′ is time t21′ (=t13+time t21), the time comparator 4b′ determines that the second total required movement time T2′ is time t21′ or less. It is determined that (T2'≤t21'). On the other hand, when the second total required download time t2' is time t22' (=t13+t22), the time comparator 4b' determines that the second total required movement time T2' is longer than time t22' (T2'>t22'). I judge. The time comparison unit 4b' outputs the time comparison result to the first download unit 4c', the second download unit 4d', and the old/new comparison unit 4f'.

A time comparison result is input to the first download unit 4c'. When the time comparison result is input, the first download unit 4c' transmits the guidance information of the next guidance point P(n+1) among the section map data of the predetermined section Z(n) through communication regardless of the result. Download from the generation unit 103 . Downloading of the guidance information is started even before the vehicle arrives at the guidance point P(n) unlike the first embodiment. In other words, the guide information is downloaded continuously from the departure point based on the departure point. For example, as shown in FIG. 11, when "T1'≤t1'", when the download of the first guidance information is completed through communication, the second guidance information is continuously downloaded from the route generation unit 103 through communication. The second guide information is guide information of the next second guide point P2 in the second section map data. When "T'(n)>t'(n)" holds, the first download unit 4c' outputs a download end signal to the second download unit 4d' when the download is completed.

The time comparison result and the download end signal are input to the second download unit 4d'. The second download unit 4d' does not download the background map information of the section map data of the predetermined section Z(n) when the time comparison result is "T'(n)≤t'(n)". For example, as shown in FIG. 11, the second download unit 4d' does not download the second background map information when the time comparison result is "T2'≤t21'". On the other hand, when the time comparison result is "T(n)>t(n)", the second download unit 4d' downloads the predetermined section Z(n ) of the section map data, the background map information is downloaded from the route generation unit 103 . For example, as shown in FIG. 11, when the time comparison result is "T2'>t22'", the second download unit 4d', after the download of the second guidance information is finished, downloads the second time period of the second section Z2 through communication. The second background map information of the section map data is downloaded from the route generation unit 103 .

A time comparison result is input to the new/old comparison unit 4f'. When the time comparison result is "T'(n)≤t'(n)", the new/old comparison unit 4f' compares the node information downloaded by communication with the external server 100 and the guidance information read from the map data storage unit 3. The stored map data corresponding to and the new/old information of the map data version are compared. Note that the new/old comparison unit 4f' does not compare the new/old information of the map data version when the time comparison result is "T'(n)>t'(n)". Other descriptions are the same as those of the new/old comparison unit 4f of the first embodiment, so are omitted.

Next, the operation of Example 2 will be described. As in the first embodiment, the actions of the second embodiment are the "external server processing action", the "route guidance processing action", and the "new/old notification processing action".

Furthermore, based on FIG. 12, the "download processing action" of the second embodiment will be described. The process of FIG. 12 is executed by the navigation control unit 4', the time prediction section 4a', the time comparison section 4b', the first download section 4c', and the second download section 4d'. The navigation control unit 4' downloads "node information and link information" from the departure point to the destination of the travel guidance route from the route generation unit 103 by communication. do.

When started, it proceeds to S41', S43' and S45' in order. First, the time prediction unit 4a' calculates and predicts the total travel time T'(n) from the departure point to the next guidance point P(n+1) in the predetermined section Z(n) (S41'). . In S41', when predicting the total required travel time T'(n), the vehicle speed of the host vehicle and the like are taken into consideration. Therefore, when predicting the total required travel time T′(n), it is better to consider a plurality of pieces of information than to consider only the vehicle speed and the distance of the predetermined section Z(n). T'(n) can be predicted.

Next, the time prediction unit 4a' calculates the time required for continuous download time from the starting point and the time required for downloading the section map data of the predetermined section Z(n) (required download time t(n)). The total required download time t'(n) is predicted by calculation (S43'). Subsequently, the time comparison unit 4b' determines whether or not the total required travel time T'(n) is equal to or less than the total required download time t'(n) (S45').

If the determination in S45' is affirmative, the process proceeds to S47' and S49' in that order. On the other hand, if the determination in S45' is negative, the process proceeds to S51' and S53' in order. If the determination in S53' is affirmative, the process proceeds to S55' and S57'. Further, when the determination in S53' is affirmative, the first download section 4c' outputs a download end signal to the second download section 4d'. Other descriptions of S47' to S57' in the second embodiment are the same as the descriptions of S45 to S57 in the first embodiment, so they are omitted.

By proceeding to S51', S53', S55', and S57' in this order, the background map information is downloaded after the guidance information has been downloaded. Therefore, as in the first embodiment, it is possible to reliably download the guidance information necessary for route guidance in time for the next guidance location P(n+1).

Then, the navigation control unit 4' determines whether or not the next guidance point P(n+1) is the destination (S61'). Other explanations of S61' are the same as those of S61 of the first embodiment, so the explanation is omitted.

If the determination in S61' is negative, the process proceeds to S65'. Then, by the navigation control unit 4', the current predetermined section Z(n), the guidance point P(n) indicating the start point of the current predetermined section Z(n), and the next guidance point P(n+1) indicating the end point of the current predetermined section Z(n). and are updated (S65'). After completing the process of S65', the process returns to S41', and the flow from S41' to S65' is repeated. Then, when the determination in S61' is affirmative, the process proceeds to the end. The rest of the description of S65' is the same as the description of S65 in the first embodiment, so it is omitted.

Next, based on FIG. 13, the download operation of the flow chart of FIG. 12 will be described.

First, since the vehicle position is the initial guidance point P0 as the departure point, the first guidance information of the first guidance point P1 or the first guidance information of the first section Z1 from the initial guidance point P0 to the next first guidance point P1. Section map data is downloaded. At this time, a first travel total required time T1' and a first download total required time t1' are predicted. Here, when the vehicle position is at the initial guidance point P0, the first total travel time T1' is the first travel time T1, and the first download total time t1' is the first download travel time t1. be. Then, since it is determined that the first travel total required time T1' is equal to or shorter than the first download total required time t1', only the first guide information of the first section map data is downloaded. Therefore, the first background map information of the first section map data is not downloaded.

Next, when the download of the first guidance information is completed, the first section Z1, the initial guidance point P0, and the first guidance point P1 are updated to the second section Z2, the first guidance point P1, and the second guidance point P2, respectively. be done. Before the vehicle position reaches the first guidance point P1, when the download of the first guidance information is completed, the second guidance information of the second guidance point P2 or from the first guidance point P1 follows. The second section map data of the second section Z2 up to the second guide point P2 is downloaded. At this time, a second total travel time T2' and a second total download time t2' are predicted. The second total required travel time T2' is the time required to travel from the initial guidance point P0 to the next second guided point P2, so it is the sum of the first total travel time T1' and the second travel required time T2. . The second total required download time t2' is the sum of the time t13 required for continuous download time from the departure point and the second required download time t2 of the second section map data. Here, since it is determined that the second total travel time T2' is longer than the second total download time t2', the download of the second section map data is executed. When downloading the second section map data, the second background map information is downloaded after the download of the second guide information is completed.

Subsequently, when the download of the second background map information is completed, the second section Z2, the first guide point P1, and the second guide point P2 are transferred to the third section Z3, the second guide point P2, and the third guide point P3. updated respectively. Before the vehicle position reaches the second guide point P2, when the download of the second background map information is completed, the third guide information of the third guide point P3 or the second guide point P2 is displayed. The third section map data of the third section Z3 up to the third guidance point P3 is downloaded. At this time, a third total travel time T3' and a third total download time t3' are predicted. The third total required movement time T3' is the time required to move from the initial guidance point P0 to the next third guidance point P3, so it is the total time of the second total movement time T2' and the third total movement time T3. . The third total required download time t3' is the sum of the time required for continuous download time from the departure point, that is, the second total required download time t2' and the third required download time t3 of the third section map data. Become. Here, since it is determined that the third total travel time T3' is longer than the third total download time t3', the download of the third section map data is executed. When downloading the third section map data, the third background map information is downloaded after the download of the third guidance information is completed.

When the download of the third background map information is completed, subsequently, the guide information of the next guide point P(n+1) or the section map data of the predetermined section Z(n) is downloaded. During this continuous download, as described above, the total required travel time T'(n) and the total required download time t'(n) are predicted. Since the total required travel time T'(n) is the time required to travel from the initial guidance point P0 to the next guided point P(n+1), the previous total required travel time T'(n-1) and the travel required It becomes the total time of time T(n). The total required download time t'(n) is the time required for continuous download time from the departure point, that is, the total required download time t'(n-1) one before, and the section map data of the predetermined section Z(n). and the required download time t(n). Here, the predicted total required travel time T'(n) and the total required download time t'(n) are compared, and based on the time comparison result, guidance information for the next guidance point P(n+1) or a predetermined section Z( n) section map data is downloaded. If it is determined that the next guide point P(n+1) is the destination after either download, the flow chart of FIG. 12 ends.

In this way, since the guidance information is downloaded regardless of the time comparison result, appropriate route guidance to the user is performed at the next guidance point P(n+1) regardless of whether or not the background map information is downloaded. . In addition, since the data volume of the guidance information is smaller than the data volume of the background map information, the guidance information can be reliably downloaded within the total required travel time T'(n).

Then, when the time comparison result is "T'(n)≤t'(n)", the background map information is not downloaded. For example, in FIG. 13, even if the first background map information is downloaded, the download ends after the vehicle passes through the first section Z1. Then, even if the first background map information is downloaded, the first background map information is useless because it is unnecessary for route guidance. In addition, the download of the first background map information ends at unnecessary timing. It should be noted that if the download of the first background map information is costly, the additional cost will be incurred. On the other hand, in the second embodiment, whether or not to download the background map information is determined according to the time comparison result. That is, when the time comparison result is "T'(n)≤t'(n)", the background map information is not downloaded, so that the background map information of the section map data is not wasted. . Even in this case, since the guidance information is downloaded, appropriate route guidance to the user is performed. Therefore, wasteful downloading of background map information is eliminated, and appropriate route guidance is provided to the user.

On the other hand, when the time comparison result is "T'(n)>t'(n)", the background map information is downloaded. For example, in FIG. 13, when the second background map information is downloaded, the download ends before the vehicle passes through the second section Z2. Then, even if the second background map information is downloaded, the second background map information will not be wasted because it is necessary for route guidance. As a result, the background map information can be used for the route guidance of the second section Z2 at the necessary timing after the background map information is downloaded, so detailed route guidance can be performed. Since the external map data is not downloaded all at once, route guidance can be provided using the latest background map information without waiting for the completion of downloading the external map data.

Furthermore, by selecting the information to be downloaded based on the time comparison results, it is possible to eliminate wasteful downloads while maintaining the quality of route guidance, and to enable route guidance based on the latest map data.

Furthermore, the total required travel time T'(n) and the total required download time t'(n) are predicted, and by comparing the two total times, the guidance information Alternatively, the download of the section map data of the predetermined section Z(n) is controlled. For example, when "T1'≤t1'" as shown in FIG. 13, after the first guidance information is downloaded, the second section map data is downloaded continuously. Furthermore, after the second section map data is downloaded, the third section map data is downloaded continuously. In this way, the download of the guidance information or the section map data of the predetermined section Z(n) is controlled continuously from the departure point. Therefore, by effectively using time, there is no download interruption time, and the possibility of downloading the background map information in addition to the guide information in the section map data of the predetermined section Z(n) increases. In addition, it is possible to download the section map data ahead of the traveling direction of the own vehicle.

Next, the effect will be explained. With the map data download method and the map recording device of the second embodiment, the effects described in (1) to (3) and (5) to (8) of the first embodiment are obtained. Further, in the map data download method of the second embodiment, the following effect (9) can be obtained.

(9) The user controller (navigation control unit 4') does the following: The required travel time T(n) is predicted as the total required travel time T'(n) required for travel from the departure point to the next guidance point P(n+1) in the predetermined section Z(n) (S41'). . The required download time t(n) is defined as the total required download time t'(n) of the time required for continuous download time from the departure point and the time required for downloading the section map data of the predetermined section Z(n). Predict (S43'). The total required travel time T'(n) and the total required download time t'(n) are compared (S45'). As a departure point reference, the first information (guidance information) or section map data is continuously downloaded from the departure point (S47' and S49' and S51', S53', S55' and S57').

In this way, the first information (guidance information) or the section map data is continuously downloaded from the departure point as the departure point reference, so that the download interruption time is eliminated. Therefore, it is possible to increase the possibility that not only the first information (guidance information) but also the second information (background map information) of the section map data of the predetermined section Z(n) can be downloaded.

The map data download method and the map recording device of the present disclosure have been described above based on the first and second embodiments, but the specific configuration is not limited to these embodiments, and the present invention is described in the claims. Design changes, additions, etc. are permitted as long as they do not depart from the gist of the invention according to each claim of the scope.

Examples 1 and 2 show examples in which the route generation unit 103 transmits the node information and the link information from the departure point to the destination to the navigation control units 4 and 4' by communication. However, it is not limited to this. For example, the node information and link information for the next section may be transmitted before the vehicle arrives at the guidance location indicating the starting point of the next predetermined section. In short, the node information and the link information on which the own vehicle will travel should be transmitted before the own vehicle reaches the predetermined point.

In Embodiments 1 and 2, when online, the navigation control units 4 and 4' transmit the vehicle position information and the destination information to the external server 100, and the route generating section 103 of the external server 100 generates a travel guidance route. I showed an example that generates . However, it is not limited to this. For example, even when online, the navigation control unit first generates a travel guidance route. Next, in addition to the vehicle position information and the destination information, the travel guidance route may be transmitted from the navigation control unit to the external server. Next, in the external server, the external map data based on the travel guidance route is divided into sections for each guidance point P(n) on the travel guidance route, and the section map data of each section is divided into "guidance information" and "background map information". You may divide into two and transmit.

In the first and second embodiments, when both the guide information and the background map information are downloaded based on the result of the time comparison, the background map information is downloaded after the guide information is downloaded. However, it is not limited to this. For example, downloading of guide information and background map information may be started simultaneously. Even if they are started at the same time, since the amount of data of the guide information is smaller than that of the background map information, the download ends first.

In the first and second embodiments, the first information is guidance information and the second information is background map information. However, it is not limited to this. In short, the first information may include other information in addition to the guidance information, and as a result, the first information may have a data amount smaller than that of the second information.

In Embodiments 1 and 2, an example was shown in which section map data is divided into two parts, ie, guide information and background map information, and downloaded. However, it is not limited to this. For example, the section map data may be divided into three. Of the road information, terrain information, and facility information included in the background map information, the facility information may be downloaded last, with the facility information separated from the road information and terrain information.

In the first embodiment, when the own vehicle arrives at the next guide location P(n+1), the required travel time T(n) and the required download time t(n) are predicted, and the two required times are compared and determined. Indicated. In the second embodiment, after the download of guidance information or section map data is completed, the total required travel time T'(n) and the total required download time t'(n) are predicted, and the two total required times are compared and determined. showed that. However, it is not limited to this. For example, after the two (total) required times are predicted and compared and determined, and before the download of the guidance information or section map data is completed, the two required times for the next section are estimated by another process. Prediction and comparison judgment may be performed. In the first embodiment, after the download of the guidance information or the section map data is finished and before the vehicle arrives at the next guidance point P(n+1), another process is performed to determine the two required times for the next section. may be predicted and compared.

In the first embodiment, the new/old comparison unit 4f does not compare the new/old information of the map data version when the time comparison result is "T(n)>t(n)". In the second embodiment, the old/new comparison unit 4f' does not compare the new/old information of the map data version when the time comparison result is "T'(n)>t'(n)". However, it is not limited to this. For example, when both the guide information and the background map information are downloaded based on the result of the time comparison, the old/new comparison may be performed until the download of the background map information is completed. Thereby, when the map data versions do not match, the output unit may output the old display to the notification device together with the guidance route information.

In Example 1 and Example 2, the example of displaying the old information when the map data versions do not match was shown. However, it is not limited to this. For example, when the map data versions do not match, the old information may be displayed only when the intersection is enlarged or when the deviation is displayed in route guidance. Here, "at the time of enlarged intersection display" indicates the time at which the own vehicle turns right or left at an intersection. "During display of deviation" indicates a time when the downloaded node information is deviated from the background map information read from the stored map data. In particular, by displaying the old information at the time of enlarged display of the intersection where the vehicle turns, the user is careful not to misidentify the intersection. Therefore, it is possible to draw the user's attention to the enlarged display of the intersection where the vehicle turns in the route guidance. Furthermore, by displaying the old information when the deviation is displayed, it is possible to suppress the user's confusion about the route guidance when the deviation is displayed in the route guidance.

In Embodiments 1 and 2, examples of displaying old information by displaying an icon in which "Old" is enclosed in a square at the upper left are shown. However, it is not limited to this. For example, "Old" may be displayed instead of "Old", and the display position may be upper right instead of upper left. Further, the icon may be a pictorial icon that indicates that the old information is displayed, instead of a character surrounded by a square. Furthermore, the color of the route guidance arrow may be changed instead of the icon. For example, if the arrow for route guidance without display of old information is green, the arrow for route guidance with display of old information is changed to red. In short, old information may be displayed so that the user can recognize new and old information of the map data during route guidance.

In Example 1 and Example 2, an example was shown in which route guidance or the like is notified by the display of the HMI device 6 included in the notification device. However, it is not limited to this. For example, an HMI device included in the notification device may notify the route guidance or the like by voice, or may notify the route guidance or the like by both the display and the voice of the HMI device. In short, it suffices if route guidance or the like can be notified.

In the first and second embodiments, the touch panel 5 is used as the data input means. However, it is not limited to this. For example, the data input means may be a switch, a remote control, or a portable terminal such as a smart phone. By operating a switch or a remote controller, or by remotely operating a mobile terminal such as a smartphone connected via Bluetooth (registered trademark), the user indicates the destination of the vehicle to the navigation control unit. input. In short, it suffices if the user can input the destination of the vehicle to the navigation control unit by operating the data input means.

In Embodiments 1 and 2, an example of applying the map data download method and the map recording device of the present disclosure to a car navigation system mounted on a vehicle has been described. However, the method of downloading map data and the map recording device of the present disclosure may be applied to a navigation system installed in a mobile terminal such as a smart phone.

1 navigation device 2 in-vehicle sensor 24 in-vehicle data communication device 3 map data storage unit (memory)
4, 4' navigation control unit (user controller)
40, 40' map recording devices 4a, 4a' time prediction units 4b, 4b' time comparison units 4c, 4c' first download units 4d, 4d' second download unit 4e display route generation units 4f, 4f' new/old comparison unit 4g Output unit 6 HMI device (notification device, display device)
100 External server 101 External data communication device 102 Latest map data storage unit 103 Route generation unit P(n) Guidance location P(n+1) Next guidance location T(n) Travel time t(n) Download time T'(n) ) Total required travel time t'(n) Total required download time Z(n) Predetermined section

Claims (7)

In a method for downloading map data through communication between an external server storing server map data and a user controller executing route guidance based on user map data stored in a memory and a driving guidance route,
When the user controller communicates with the external server to download the server map data from the departure point to the destination by dividing it into section map data for each section for each guidance point on the travel guidance route,
Predicting the travel time required to move a predetermined section from the guidance point to the next guidance point,
estimating a required download time required to download the section map data of the predetermined section;
Comparing the required travel time and the required download time,
Among the first information and the second information that constitute the section map data, the first information that is used for route guidance at the next guidance point in the predetermined section and has a data amount smaller than that of the second information is time-varying. Download regardless of the comparison result,
When it is determined from the time comparison result that the required travel time is less than or equal to the required download time, the second information is not downloaded, and when it is determined that the required travel time is longer than the required download time, the A method of downloading map data, comprising: downloading the second information after completing the downloading of the first information. In the map data download method according to claim 1,
A method of downloading map data, wherein the second information is background map information. In the map data download method according to claim 1 or 2,
A method of downloading map data, wherein the user controller downloads the first information or the section map data when the user arrives at the guidance location with reference to the guidance location. In the map data download method according to claim 1 or 2,
The user controller is
Predicting the required travel time as a total required travel time required for travel from the departure point to the guidance point next to the predetermined section,
predicting the required download time as the total required download time of the time required for continuous download time from the departure point and the time required for downloading the section map data of the predetermined section;
Comparing the total required travel time and the total required download time,
A method of downloading map data, characterized in that the first information or the section map data is continuously downloaded from a point of departure as a reference point of departure. In the map data download method according to any one of claims 1 to 4,
The memory and the user controller are mounted on a vehicle,
When the user controller predicts the required travel time or the required travel time as a total required travel time required for travel from the departure point to the guidance point next to the predetermined section, the user controller predicts the vehicle speed and the predetermined section , traffic information, and characteristics of the predetermined section. In the map data download method according to any one of claims 1 to 5,
The memory, the user controller, and the notification device are mounted on a vehicle,
When the user controller downloads the server map data by communicating with the external server,
downloading node information prior to downloading the first information;
When only the first information is downloaded according to the time comparison result, the map data version of the downloaded node information and the map data version of the user map data corresponding to the first information read from the memory are new or old. compare information,
If the map data versions match each other as a result of comparing the new and old map data versions, the new and old information of the map data versions is not output to the notification device, and if the map data versions do not match, the map data versions are not output. A method of downloading map data, characterized in that the old information of the map data is output to the notification device. In a map recording device through communication between an external server storing server map data and a user controller executing route guidance based on user map data and a driving guidance route stored in a memory,
When the user controller communicates with the external server to download the server map data from the departure point to the destination by dividing it into section map data for each section for each guidance point on the travel guidance route,
a time prediction unit that predicts a travel time required to travel a predetermined section from the guide location to the next guide location, and predicts a download time required to download the section map data of the predetermined section;
a time comparison unit that compares the required travel time and the required download time;
Among the first information and the second information that constitute the section map data, the first information that is used for route guidance at the next guidance point in the predetermined section and has a data amount smaller than that of the second information is time-varying. a first download unit that downloads regardless of the comparison result;
When it is determined from the time comparison result that the required travel time is less than or equal to the required download time, the second information is not downloaded, and when it is determined that the required travel time is longer than the required download time, the a second download unit that downloads the second information after the download of the first information is completed;
A map recording device comprising:

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