JP2008096445A - Route searching method of navigation device and traffic information displaying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To search the recommended route using the collected traffic information in the past. <P>SOLUTION: In a map/statistical traffic data memory device 3, map data including link data of each link constituting the road on the map and the statistical data including the travelling time or travelling speed of each link to be determined from statistical values of traffic information collected in the past and classified for every searching condition being the collecting condition of traffic information are stored. An inboard navigation device searches the recommended route between the departure spot and the destination using the map data stored in the map/statistical traffic data memory 3 and the statistical data being the searching condition corresponding to the kind of the day and the kind of weather selected from among the statistical data stored in the map/statistical traffic data memory device 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a navigation device, and more particularly to a route search technology and a traffic information display technology for an in-vehicle navigation device.

  Patent Document 1 discloses a technique for changing a display form of a predetermined road on a map displayed on a display in accordance with the degree of congestion in a navigation device. For example, when the predetermined road is included in the route searched by the route search, the road included in the route of the predetermined road is determined by the traffic information collected in the past predetermined period. Display format according to the degree of traffic congestion. Here, the traffic information collected in the past predetermined period may be classified for each predetermined time zone. In this way, by changing the traffic information of the road adopted to determine the display form of the road according to the time, the display form of the road can be changed according to the traffic congestion that changes in real time. .

JP-A-10-82644

  However, since the technique described in Patent Document 1 does not consider using the traffic information collected in the past for route search, there is a possibility that the recommended route with the minimum cost (travel time) cannot be searched. Is expensive. In the technique described in Patent Document 1, only the time zone is considered as a condition for changing the tendency of traffic congestion on the road. In addition, it does not consider a display form that allows the operator to recognize changes in road congestion due to changes in time zones.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to make it possible to search a recommended route with higher accuracy by using traffic information collected in the past. Another object of the present invention is to make it possible to display the traffic jam tendency on the road in more detail according to the display form in which the operator can recognize the change of the traffic jam due to the change of the time zone.

  In order to solve the above problems, in the route search method of the present invention, map data including link data of each link constituting a road on a map is stored in a storage device of the navigation device. Further, statistical data including travel time or moving speed of each link determined from statistical values of traffic information collected in the past is classified and stored for each traffic information collection condition. In the setting step of setting a departure point, a destination and a collection condition in the navigation device, the map data stored in the storage device, and the statistical data stored in the storage device A route search step of searching, as a recommended route, a route having the shortest travel time between the departure point and the destination set in the setting step, using statistical data corresponding to the set collection condition.

  In this way, by using the statistical data of each link that matches the collection conditions, it is possible to search for a recommended route with the minimum cost (travel time) with high accuracy.

  In the traffic information display method of the present invention, map data including link data of each link constituting a road on the map is stored in the storage device of the navigation device. Further, the degree of congestion for each link time zone determined from the statistics of traffic information collected in the past is classified and stored for each traffic information collection condition. Then, a setting step for setting the collection conditions in the navigation device, and statistical data corresponding to the collection conditions set in the setting step among the statistical data of each link included in the map data of the map displayed on the display device A reading step for reading out from the storage device, and a traffic information display step for displaying the degree of congestion for each time slot of each link specified by the read statistical data superimposed on the map displayed on the display device; , Do.

  In this way, by using the statistical data of each link that matches the collection conditions, it is possible to display the traffic congestion tendency on the road in more detail. In addition, since the congestion degree for each time zone indicated by the link statistical data is displayed over the link in the map, it is easy to grasp the change in the traffic jam due to the change in the time zone.

  In the present invention, the collection condition may include at least one of a day type such as a weekday, a holiday, an event day (bon festival, new year, etc.) and a weather type such as sunny, rainy, and snowy. Road congestion shows different trends depending on the type of day and the type of weather. Therefore, the statistical data is classified and stored for each day type or weather type, which is a collection condition of the traffic information that is the source of the statistical data, so that the route search method of the present invention can achieve the minimum cost (travel time). It becomes possible to search the recommended route to become more accurate. Further, according to the traffic information display method of the present invention, it is possible to display the traffic jam tendency on the road more appropriately.

  As described above, according to the present invention, a recommended route can be searched with high accuracy using traffic information collected in the past. Further, the traffic congestion tendency on the road can be displayed in more detail according to the display form in which the operator can recognize the change in the traffic congestion due to the change of the time zone.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of an in-vehicle navigation device to which an embodiment of the present invention is applied.

  As shown in the figure, the in-vehicle navigation device of the present embodiment includes an arithmetic processing unit 1, a display 2, a map / statistical traffic data storage device 3, a voice input / output device 4, an input device 5, and a wheel speed sensor. 6, a geomagnetic sensor 7, a gyro sensor 8, a GPS (Ground Positioning System) receiver 9, a weather information receiver 10, and an in-vehicle LAN device 11.

  The arithmetic processing unit 1 is a central unit that performs various processes. For example, the current location is detected based on information output from the various sensors 6 to 8 and the GPS receiver 9, and the map / statistical traffic data storage device 3 stores map data necessary for display based on the obtained current location information. Read from. Further, the read map data is developed in graphics, and a mark indicating the current location is superimposed on the displayed map 2 and displayed on the display 2, or the map data and statistical traffic data stored in the map / statistical traffic data storage device 3 are used. Then, an optimum route (recommended route) connecting the destination instructed by the user and the departure place (for example, the current location) is searched, and the user is guided using the voice input / output device 4 and the display 2.

  The display 2 is a unit that displays graphics information generated by the arithmetic processing unit 1, and is configured by a CRT, a liquid crystal display, or the like. The signal S1 between the arithmetic processing unit 1 and the display 2 is generally connected by an RGB signal or an NTSC (National Television System Committee) signal.

  The map / statistical traffic data storage device 3 includes a storage medium such as a CD-ROM, DVD-ROM, HDD, or IC card. In this storage medium, map data and statistical traffic data are stored.

  FIG. 2 is a diagram illustrating a configuration example of map data stored in the map / statistical traffic data storage device 3. As shown in the figure, map data 31 is stored for each mesh region obtained by dividing the map into a plurality of parts. The map data 31 includes a mesh area identification code (mesh ID) 311 and link data 312 of each link constituting a road included in the mesh area. The link data 312 includes a link identification code (link ID) 3121, coordinate information 3122 of two nodes (start node and end node) constituting the link, road type information 3123 including the link, and a link indicating the link length. Long information 3124, link travel time (or moving speed) information 3125, link ID (connection link ID) 3126 of a link connected to each of the two nodes, and the like. Here, by distinguishing the start node and the end node for the two nodes constituting the link, the upward direction and the downward direction of the same road are managed as different links. The map data 31 also includes information (name, type, coordinate information, etc.) on map components other than roads included in the corresponding mesh area.

  FIG. 3 is a diagram illustrating a configuration example of statistical traffic data stored in the map / statistical traffic data storage device 3. As shown in the figure, statistical traffic data 32 is stored for each mesh area described above. The statistical traffic data 32 is management data for managing the mesh ID 321 of the mesh area and the traffic information statistical value (statistical value of the traffic information collected in the past) of each link constituting the road included in the mesh area. 322. The mesh ID 321 is the same as the mesh ID 311 of the map data 31. The management data 322 includes a plurality of tables 3221 to 2224 having a hierarchical structure.

  The table 3221 is a table for registering the day type. The type of day may be determined for each unit indicating a tendency of different traffic information statistics. Here, weekdays before holidays, “weekdays (before holidays)”, weekdays after holidays, “weekdays (after holidays)”, weekdays before special days such as Bon, New Year, etc. Weekdays of the daylight “Weekdays (after the singular days)”, Other weekdays “Weekdays (general)”, The first days of the singular days “Holidays (beginning of the singular days)”, All day of the singular days “Holidays (end of the singular days)”, etc. The holiday “holiday (general)” is included.

  The table 3222 is a table for registering the weather type, and is provided for each day type registered in the table 3221. The type of weather may be determined for each unit indicating a tendency of different traffic information statistics. Here, “sunny / cloudy”, “rain”, “heavy rain”, “snow”, “heavy snow” are included as the types of weather.

  The table 3223 is a table for registering the link ID of each link constituting the road included in the mesh area registered by the mesh ID 321, and is provided for each type of weather registered in the table 3222. The same link ID as the link ID 3121 of the map data 31 is used.

  The table 3224 is a table for registering traffic information statistical values for each time zone, and is provided for each link ID registered in the table 3223. The traffic information statistics for each time zone include link travel time (or travel speed), link travel time (or travel speed) variation (variance), link congestion, which are specified by a plurality of traffic information that is the basis of these traffic information. And an information source (such as VICS) from which the plurality of traffic information is obtained. Further, the traffic information statistical value for each time zone is classified according to the traffic information collection conditions (the type of day and the weather type when the original traffic information was collected) and the target link. That is, the target link of the traffic information statistical value for each time zone registered in a certain table 3224 is a link specified by the link ID of the table 3223 associated with this table 3224, and these statistical values The original traffic information is the weather specified by the weather type in the table 3222 associated with the table 3223 in which the link ID is registered, and the table in which the weather type is registered. 3 is traffic information collected on the day specified by the type of day in the table 3221 associated with 3222.

  As described above, the traffic information statistical value includes the degree of link congestion (in FIG. 3, three levels of congestion, congestion, and smoothness). In general, in order to calculate the degree of congestion, it is necessary to compare and determine the speed limit of each link and the moving speed (calculated from the link length and travel time) obtained from the traffic information statistics. By including the degree of congestion in the traffic information statistics in advance, the degree of congestion for each link can be determined without using the speed limit information for each link, eliminating the need to provide speed limit information for link data. . Thereby, the data size of link data can be made small.

  In addition, the traffic information statistical value includes an information source that is information about the source of the plurality of traffic information that is the basis of these statistics. By including the information source in advance in the traffic information statistical value and using it for display, it becomes possible to make the user judge the likelihood of the traffic information statistical value.

  Further, the traffic information statistical value includes the degree of dispersion (dispersion degree) of the link travel time specified by the plurality of pieces of traffic information that is the basis of these statistics. By including the degree of variation in the traffic information statistical value in advance and using it for display, it becomes possible for the user to determine the reliability of the link travel time specified from the traffic information statistical value.

  In the map / statistical traffic data storage device 3, in addition to the above-described map data and statistical traffic data, a conversion table for identifying a mesh ID of a mesh region including a point specified by the coordinate information from the coordinate information. (Referred to as a first conversion table) is stored. In addition, a conversion table (referred to as a second conversion table) for specifying the day type managed in the table 3221 from the date is stored.

  FIG. 15 is a diagram illustrating a configuration example of the second conversion table. As illustrated, a date 331 and a date type 332 corresponding to the date 331 are registered in association with each other. By using such a second conversion table, the type of day can be easily specified from the date. For example, when the process of specifying the day type from the date by calculation logic is executed by the software incorporated in the in-vehicle navigation device, in order to further subdivide the day type classification, the in-vehicle navigation device The embedded software must be rewritten. In addition, the specific processing for special days such as year-end, tray, and GW becomes complicated. In this respect, since the conversion table as shown in FIG. 15 is used in this embodiment, the vehicle-mounted navigation device can be obtained by simply replacing the DVD-ROM or CD-ROM constituting the map / statistical traffic data storage device 3. It is possible to deal with classification subdivisions without changing the software embedded in the. In addition, by making it possible to identify the specific date from the conversion table, it is possible to cope with complicated processing.

  Returning to FIG. 1, the description will be continued. The voice input / output device 4 converts the message to the user generated by the arithmetic processing unit 1 into a voice signal and outputs it, and recognizes the voice uttered by the user and transfers the content to the arithmetic processing unit 1.

  The input device 5 is a unit that receives instructions from the user, and includes a hardware switch such as a scroll key and a scale change key, a joystick, a touch panel pasted on a display, and the like.

  The sensors 6 to 8 and the GPS receiver 9 are used for detecting the current location (own vehicle position) by the vehicle-mounted navigation device. The wheel speed sensor 6 measures the distance from the product of the wheel circumference and the measured number of rotations of the wheel, and further measures the angle at which the moving body is bent from the difference in the number of rotations of the paired wheels. The geomagnetic sensor 7 detects the magnetic field held by the earth and detects the direction in which the moving body is facing. The gyro 8 is configured by an optical fiber gyro, a vibration gyro, or the like, and detects an angle at which the moving body rotates. The GPS receiver 9 receives a signal from a GPS satellite and measures the distance between the mobile body and the GPS satellite and the rate of change of the distance with respect to three or more satellites, so that the current location, travel direction, and travel direction of the mobile body Measure.

  The in-vehicle LAN device 11 receives various information of the vehicle on which the in-vehicle navigation device of the present embodiment is mounted, such as door opening / closing information, light lighting state information, engine status and failure diagnosis result.

  Then, the weather information receiving apparatus 10 obtains weather information from a weather center that provides a weather information providing service, for example, using FM multiplex broadcasting. Here, the weather information is registered in the mesh ID of the mesh area included in the target area (the same as the mesh ID 311 of the map data 31) and the weather type of the target area (the table 3222 of the statistical traffic data 32). Type of weather) and information on the time zone (referred to as the target time zone) in which the weather continues.

  Instead of providing the weather information receiving device 10, the in-vehicle LAN device 11 is used to display the wiper operation status of the vehicle on which the in-vehicle navigation device of the present embodiment is mounted and the detected value of the outside air temperature sensor mounted on the vehicle. And means for judging the weather based on the reception result.

  FIG. 4 is a diagram illustrating a hardware configuration of the arithmetic processing unit 1.

As illustrated, the arithmetic processing unit 1 has a configuration in which devices are connected by a bus 32. The arithmetic processing unit 1 includes a CPU (Central Processing Unit) 21 that executes various processes such as numerical calculation and control of each device, and map data, statistical traffic data, and arithmetic data read from the map / statistical traffic data storage device 3. RAM (Random Access Memory) 22, ROM (Read Only Memory) 23 for storing programs and data, and DMA (Direct Memory Access) 24 for executing data transfer between memories and between each memory and each device. A graphics controller 25 that performs graphics rendering and performs display control, a video random access memory (VRAM) 26 that stores graphics image data, and R A color palette 27 for converting to a B signal, an A / D converter 28 for converting an analog signal to a digital signal, an SCI (Serial Communication Interface) 29 for converting a serial signal into a parallel signal synchronized with the bus, and a parallel signal A PIO (Parallel Input / Output) 30 mounted on the bus in synchronization with the bus and a counter 31 for integrating the pulse signal are provided.

  FIG. 5 is a diagram illustrating a functional configuration of the arithmetic processing unit 1.

  As shown in the figure, the calculation processing unit 1 includes a user operation analysis unit 41, a route search unit 42, a route storage unit 43, a route guidance unit 44, a map display processing unit 45, a current position calculation unit 46, A map match processing unit 47, a data reading unit 48, a trajectory storage unit 49, a menu display processing unit 50, and a graphics processing unit 51 are provided.

  The current position calculation unit 46 uses distance data and angle data obtained as a result of integrating the distance pulse data S5 measured by the wheel speed sensor 6 and the angular acceleration data S7 measured by the gyro 8, respectively. The current position (X ′, Y ′), which is the position after the vehicle travels, is periodically calculated from the initial position (X, Y) by performing integration, and a process of outputting to the map match processing unit 47 is performed. . Here, in order to make the relationship between the rotation angle of the host vehicle and the traveling direction coincide, reference is made to the direction data S6 obtained from the geomagnetic sensor 7 and the angle data obtained by integrating the angular acceleration data S7 obtained from the gyro 8. Estimate the absolute direction of the direction in which the vehicle is traveling. In addition, since the error accumulates when the data of the wheel speed sensor 6 and the data of the gyro 8 are respectively integrated, the error accumulated based on the position data S8 obtained from the GPS receiver 9 in a certain time period is calculated. Processing for canceling is performed, and information on the current location is output to the map match processing unit 47.

  The map match processing unit 47 compares the map data around the current location read by the data reading unit 48 with the travel locus stored in the locus storage unit 49 described later, and the road (link) having the highest shape correlation. ) A map matching process is performed in which the current location output from the current position calculation unit 46 is matched. Since the current position information obtained by the current position calculation unit 46 includes a sensor error, map matching processing is performed for the purpose of further improving the position accuracy. As a result, the current location often coincides with the traveling road.

  The trajectory storage unit 49 stores information on the current location on which the map match processing has been performed by the map match processing unit 47 as trajectory data every time the vehicle travels a predetermined distance. The trajectory data is used to draw a trajectory mark on the road on the map corresponding to the road that has been traveled so far.

  The user operation analysis unit 41 receives a request from the user input to the input device 5, analyzes the request content, and controls each unit of the arithmetic processing unit 1 so that processing corresponding to the request content is executed. To do. For example, when the user requests a search for a recommended route, the map display unit 45 is requested to display a map on the display 2 in order to set a departure point and a destination, and further, from the departure point to the destination. Requests the route search unit 42 to calculate a route.

  The route search unit 42 uses the Dijkstra method or the like, and is the route that can reach the destination in the shortest time (the cost (travel time)) among the routes connecting the two specified points (departure point, destination). Are searched from the map data, and the obtained route is stored in the route storage unit 43 as a recommended route. In the present embodiment, in order to calculate the cost of a route connecting two points, the statistical traffic data stored in the map / statistical traffic data storage device 3, that is, for each condition such as the type of day and the type of weather The traffic information statistical value for each time zone of each link classified as (1) is used (see FIG. 3).

  The route guidance unit 44 compares the recommended route information stored in the route storage unit 43 with the current location information output from the map match processing unit 47 and determines whether the vehicle should go straight before passing the intersection or the like. The voice input / output device 4 is used to inform the user by voice, or the direction to travel is displayed on the map displayed on the display 2 to notify the user of the recommended route.

  Further, the route guidance unit 44 uses the current time and the statistical traffic data stored in the map / statistical traffic data storage device 3 to predict the estimated travel time from the current location to the destination output from the map match processing unit 47. Calculate Then, by adding the calculated estimated travel time to the current time, an expected arrival time at the destination is calculated and notified to the user.

  Furthermore, the route guidance unit 44 measures the actual travel time required from the departure point of the recommended route to the current location output from the map match processing unit 47. Then, the travel time is compared with the cost of the section from the departure point to the current location in the cost (travel time) used by the route search unit 42 for searching for the recommended route, and the comparison result is determined. To determine the necessity of re-searching the recommended route. If it is determined that there is a need for re-search, the route search unit 42 is requested to re-search for a recommended route with the current location output from the map match processing unit 47 as the departure location and the current time as the departure time.

  The data reading unit 48 displays map data and statistical traffic data in an area required to be displayed on the display 2 and an area required for route search (an area including a starting point and a destination) as map / statistics. It operates to prepare for reading from the traffic data storage device 3.

  The map display processing unit 45 receives the map data in the area where display on the display 2 is requested from the data reading unit 48, and the graphic processing unit 51 uses the designated scale and drawing method, roads, and other map configurations. A map drawing command is generated so as to draw a mark such as an object, a current location, a destination, an arrow for a guide route. Further, in response to a command output from the user operation analysis unit 41, statistical traffic data required to be displayed on the display 2 is received from the data reading unit 48, and traffic on each road is displayed on the map being displayed on the display 2. A map drawing command is generated so that the information statistics are displayed in an overlapping manner.

  Upon receiving a command output from the user operation analysis unit 41, the menu display processing unit 50 generates a menu drawing command so that the graphic processing unit 51 draws various types of menus and graphs.

  The graphics processing unit 51 receives commands generated by the map display processing unit 45 and the menu display processing unit 50 and develops image data to be displayed on the display 2 on the VRAM 26.

  Next, the operation of the in-vehicle navigation device having the above configuration will be described.

  First, the recommended route search operation will be described.

  FIG. 6 is a flowchart for explaining the recommended route search operation of the in-vehicle navigation device to which the present embodiment is applied. This flow is started when the user operation analysis unit 41 receives a search request for a recommended route from the user via the voice input / output device 4 or the input device 5.

  First, the user operation analysis unit 41 sets a departure point, a destination, and a departure time in the route search unit 43 (S1001 to S1003).

  Here, the starting point and the destination to be set are stored in the map / statistical traffic data by the user operation analysis unit 41 on the display 2 through the menu display processing unit 50 and the graphics processing unit 51 and through the data reading unit 48. Information on the map components registered in the map data read from the device 3 is displayed, and the user selects the information on the displayed map components from the voice input / output device 4 or the input device 5. You may do it. Alternatively, information on a location (registration location) registered in advance in a storage device such as the RAM 22 is displayed by the user, and information on the registered location being displayed is displayed by the user via the voice input / output device 4 or the input device 5. You may make it select from inside. Furthermore, the user operation analysis unit 41 specifies the map data read from the map / statistical traffic data storage device 3 via the data reading unit 48 on the display 2 via the map display processing unit 45 and the graphics processing unit 51. The map to be displayed may be displayed and selected by receiving a designation of a point on the map from the user via the voice input / output device 4 or the input device 5.

  When the current location is set as the departure location, the designation of the departure location by the user may be omitted. Also, when the current time is set as the departure time, the designation of the departure time by the user may be omitted. In the present embodiment, a plurality of departure times can be set. For example, when the user gives an instruction to set a plurality of departure times via the voice input / output device 4 or the input device 5, the user operation analysis unit 41 uses the current time or the user specified time as the first departure time A plurality of departure times are set every predetermined time interval.

  When the departure point, the destination, and the departure time are set in the route search unit 42 as described above, the user operation analysis unit 41 outputs a route search instruction to the route search unit 42.

  In response to this, the route search unit 42 specifies the mesh ID of the mesh region including the point specified by the coordinate information from the map / statistical traffic data storage device 3 via the data reading unit 48. Read the first conversion table. Then, using the first conversion table, the mesh ID of each mesh region included in the region including the set starting point and destination is specified. Next, each link data 312 registered in each map data 31 having the identified mesh ID is obtained from the map / statistical traffic data storage device 3 via the data reading unit 48 (S1004). Next, the second conversion table for specifying the type of day managed in the table 3221 of the statistical traffic data 32 is read from the map / statistical traffic data storage device 3 through the data reading unit 48. . Then, using the second conversion table, the type of today (departure date) is specified (S1005).

  If the date of departure is not registered in the second conversion table, the process of specifying the day type from the date by the calculation logic is executed by the software incorporated in the in-vehicle navigation device. You may make it identify the kind of day corresponding to a day. In this way, even when the date range registered in the second conversion table is exceeded, the process can be continuously executed.

  Now, the route search unit 43 uses the link data 312 read from the map / statistical traffic data storage device 3 in S1006, and starts the end node of the link (referred to as an extracted link) extracted from the heap table in S1012 described later. A link to be a node is selected as a candidate for a link (referred to as a candidate link) that constitutes a recommended route. However, when the processing in S1012 is not performed, that is, in the initial stage where the link is not registered in the heap table, instead of selecting a link having the end node of the extracted link as a start node as a candidate link, the departure place Is selected as a candidate link (S1006).

  Here, the heap table is a table for registering the link data of the candidate link together with the total cost (total travel time) from the departure place to the end node of the candidate link, and is stored in a storage device such as a memory. The

  Next, the route search unit 43 calculates the estimated arrival time at the end node of the extracted link. This can be calculated by adding the total cost (total travel time) of the extraction links registered in the heap table to the departure time. Further, the route search unit 43 specifies the mesh ID of the mesh region where the end node of the extraction link is located using the first conversion table. However, when the process in S1012 is not performed, that is, in the initial stage where the link is not registered in the heap table, the mesh ID of the mesh area where the departure point is located is specified. A target time zone (referred to as a time zone of interest) to which the identified mesh ID and the estimated arrival time at the end node of the extraction link belong from a weather center that provides a weather information providing service via the weather information receiver 10 or the like. (S1007).

  In addition, when the means for judging the weather from the wiper operation status information and the outside temperature information received via the in-vehicle LAN device 11 is provided, the weather information judged by the means is used instead of the weather information receiving device 10. You may obtain it.

  Next, the route search unit 43 accesses the statistical traffic data 32 having the mesh ID specified in S1007 stored in the map / statistical traffic data storage device 3 via the data reading unit 48. Then, using the management data 322 of the statistical traffic data 32, for each candidate link, the traffic information statistical value of the attention time zone is specified by the type of day specified in S1005 and the weather information acquired in S1007. The traffic information statistical value associated with the type of weather to be obtained is obtained (S1008).

  Then, for each candidate link, the route search unit 43 obtains the cost (travel time) of the candidate link using the traffic information statistical value obtained in S1008 (S1009). When travel time is included in the traffic information statistics, this is used as the cost. If the travel speed is included instead of the travel time, the travel time of the link is calculated using the travel speed and the link length specified from the link data, and this is used as the cost. If there is a candidate link for which the traffic information statistical value could not be obtained in S1008, the travel time included in the link data 312 of the link candidate or the moving speed included in the link data The travel time of the link calculated using the link length is set as the cost of the candidate link.

  Next, the route search unit 43 calculates the total cost of each candidate link (total travel time from the departure point to the end node of the candidate link). Specifically, the cost of the candidate link calculated in S1009 is added to the total cost of the extracted link registered in the heap table, and the addition result is set as the total cost of the candidate link. However, at the initial stage where the extraction link is not registered in the heap table, the cost of the candidate link calculated in S1009 is set as the total cost of the candidate link. Then, the route search unit 43 adds the link data and the total cost of each candidate link to the heap table (S1010).

  Next, the route search unit 43 determines whether there is a link where the destination exists or is close to the destination (called a destination link) among the links newly added to the heap table in S1010 performed immediately before. Whether or not is checked (S1011).

  If it is determined in S1011 that there is no destination link, the route search unit 43 sorts the information of the links registered in the heap table in ascending order of the total cost, and extracts the first located link. A link with the minimum total cost is extracted from the heap table (S1012). Then, the process returns to S1006.

  On the other hand, if it is determined in S1011 that there is a destination link, the route search unit 43 performs recommended route determination processing. Specifically, a link that generates a destination link (referred to as a link having a destination link start node as an end node) is searched from the heap table, and the detected link is a link (configuration link) that constitutes a recommended route. Called). Next, it is checked whether or not the constituent link is a link where the departure place exists or is close to the departure place (referred to as a departure place link). If not, the link that generated this constituent link is searched. Then, the detected link is determined as a constituent link, and it is further checked whether or not it is a departure link. By repeating this process until it is determined that the configuration link is the departure link, each configuration link that constitutes the recommended route is determined. Then, the route search unit 43 stores, in the route storage unit 44, the link data 312 of each constituent link constituting the recommended route and the traffic information statistical value obtained in S1008 as the recommended route information at the set departure time. (S1013).

  Now, if the route search unit 43 registers the recommended route information at a certain departure time in the route storage unit 44 in S1013, all the departure times set in S1003 (as described above, a plurality of departure times are set. It is checked whether or not the recommended route information has been registered in the route storage unit 44. If it is not registered (No in S1014), the registered contents of the heap table are cleared, and the recommended route is searched for the departure time set in S1003 and the recommended route is not searched. The departure time is set (S1015), and the process returns to S1006. On the other hand, if all of them are registered (Yes in S1014), the process proceeds to S1016 to perform a recommended route display process.

  With the above processing, the travel time of each constituent link constituting the recommended route is as follows. That is, the travel time obtained from the traffic information statistics corresponding to the time zone including the departure time is used as the travel time of the first link constituting the recommended route. Further, the travel time of the nth (n ≧ 2) link constituting the recommended route corresponds to a time zone including an expected arrival time at the end node of the (n−1) th link connected to the nth link. The travel time obtained from the traffic information statistics is used.

  FIG. 7 is a flowchart for explaining the recommended route display processing in S1018 of FIG.

  First, the route search unit 42 uses the recommended route information registered in the route storage unit 44 to obtain the expected travel time of the recommended route and the expected arrival time at the destination (S2001).

  Specifically, using the link data and traffic information statistics of each link constituting the recommended route registered in the route storage unit 44 as the recommended route information, each link is performed in the same manner as S1009 in FIG. Calculate the cost of Then, the total cost of each link constituting the recommended route is set as the expected travel time of the recommended route. Further, the time obtained by adding the estimated arrival time to the departure time is set as the estimated arrival time at the destination.

  When information on a plurality of recommended routes with different departure times for the same departure place and destination is registered in the route storage unit 43, an estimated travel time and an estimated arrival time for each of the plurality of recommended routes. Find the time.

  Next, the route search unit 42 obtains the reliability / estimation error of the estimated travel time and the estimated arrival time obtained in S2001 (S2002).

  Specifically, the recommended route obtained in S2001 is configured using the degree of variation included in the traffic information statistical value of each link constituting the recommended route registered in the route storage unit 44 as recommended route information. Calculate the cost error for each link. For example, when the degree of variation is “small”, the error rate is 3%, when the degree of variation is “medium”, the error rate is 5%, and when the degree of variation is “large”, the error rate is 10%. Then, the error of the link is calculated by multiplying the cost of the link by the error rate corresponding to the degree of variation of the link. This process is performed for each link constituting the recommended route. For a link for which no traffic information statistical value is registered, the link error is calculated by multiplying the link cost by a predetermined error rate. Here, the predetermined error rate may be set to be larger (for example, 15%) than the error rate of the link in which the traffic information statistical value is registered.

  Next, the sum of the error of the cost of each link is calculated, and this is used as the estimation error of the expected travel time and the expected arrival time. Further, the ratio of the estimated error to the estimated travel time (error rate) is obtained, and the reliability of the estimated travel time and the estimated arrival time is determined according to the value. For example, the reliability is determined as “high” if the ratio is less than 5%, “medium” if it is less than 10%, and “low” if it is 10% or more.

  Note that if the predicted travel time and the predicted arrival time are determined for each of the plurality of recommended routes in S2001, the reliability / estimation error of the predicted travel time and the predicted arrival time is determined for each of the plurality of recommended routes.

  Next, the route search unit 42 determines the congestion level display section of the recommended route and the congestion level of each display section (S2003). In the present embodiment, the recommended route is divided into a plurality of sections (congestion level display sections), and the congestion level can be displayed on the display 2 in units of sections. In S2003, a process for determining this section is performed.

  This process is performed as follows, for example. That is, with reference to the congestion level included in the traffic information statistical value of each link constituting the recommended route, when adjacent links have the same congestion level, both links are assigned to the same congestion level display section. Then, the section is set to the same traffic congestion level.

  Alternatively, referring to the moving speed included in the traffic information statistical value of each link constituting the recommended route or the average value of the moving speed obtained from the travel time and the link length included in the link data, each adjacent link The average value of the moving speed belongs to the same moving speed band among a plurality of preset moving speed bands, and the road type and the speed limit included in the link data of each adjacent link are the same. The adjacent links are assigned to the same congestion level display section. Then, the section is set to a traffic congestion level according to the combination of the moving speed zone and the road type, or the ratio between the moving speed zone and the speed limit.

  Alternatively, the recommended route is divided for each of a plurality of links, and each section obtained as a result is set as a congestion level display section. For each congestion level display section, the average moving speed included in the traffic information statistical value of the plurality of links included in the section, or the average value of travel time and the link data of the plurality of links The average value of the moving speed obtained from the sum of the existing link lengths is obtained. In addition, an average value of the speed limits included in the link data of the plurality of links is obtained. Then, for each congestion level display section, the congestion level of the section is set to a congestion level corresponding to the average value of the moving speed and the ratio of the limit speed.

  A link having no traffic information statistical value is handled as a traffic level display section whose traffic level is unknown.

  If the estimated travel time and the estimated arrival time are obtained for each of the plurality of recommended routes in S2001, the congestion level display section and the congestion level of each display section are determined for each of the plurality of recommended routes.

  When the estimated travel time / expected arrival time, reliability / estimation error, and congestion level display section / congestion level of each section of each recommended route are determined as described above, the route search unit 42 Display of the information in the menu along with the origin of the destination, the destination, the departure time of each recommended route, and the information source of the traffic information statistical value included in the traffic information statistical value of each link that constitutes the relevant route It is passed to the processing unit 50 to instruct a recommended route display. In response to this, the menu display processing unit 50 knows the recommended route, the estimated travel time / the estimated arrival time, and the traffic level display section / the traffic level of each section on the display 2 via the graphics processing unit 51. As a graph display. In addition, information on the reliability / estimation error of the recommended route and the traffic information statistical value used for calculating the expected travel time / expected arrival time is also displayed (S2004).

  FIG. 8 shows an example of a recommended route graph display. In this example, a plurality of recommended route information with different departure times 803 are displayed for the same departure point 801 and destination 802. The length of the graph 804 of each recommended route is proportional to the estimated travel time 806, and the operator can determine at which departure time the recommended route is the shortest travel time.

  Further, the graph 804 includes at least one traffic level display section indicating the traffic level 805, and the length of the display section is also proportional to the travel time of the section. The operator can determine the congestion status of each recommended route by confirming the ratio shown in the graph of the congestion level display section having a high congestion level.

  Further, the reliability (estimated error) 807 of the estimated travel time (expected arrival time) is displayed in association with the estimated travel time (expected arrival time) 806 of each recommended route, and the operator can select each recommended route. It is possible to confirm how much error may occur when using. Further, an information source 808 of traffic information statistical values used for calculating the estimated travel time (expected arrival time) is displayed in association with the estimated travel time (expected arrival time) 806 of each recommended route. The operator can roughly determine the reliability of the estimated travel time (expected arrival time) 806 by referring to the information source 808.

  If the user operation analysis unit 41 receives an instruction to change to the map display mode from the user via the voice input / output device 4 or the input device 5 while the recommended route graph is being displayed (Yes in S2005). ) And inform the route search unit 42 to that effect. The route search unit 42 stores the recommended travel time / estimated arrival time, reliability / estimation error, and the congestion level display section / congestion level of each section for each recommended route. Together with the link data of each link and the information source of the traffic information statistical value included in the traffic information statistical value of each link, it is passed to the map display processing unit 45 to instruct the recommended route display.

  In response to this, the map display processing unit 45 displays the recommended route on the map via the graphics processing unit 51 so that the recommended route can be seen on the map so that the congestion level display section and the congestion level of each section can be understood. Also, the information source of the traffic information statistical value used for calculating the expected travel time / expected arrival time, reliability / estimation error, and expected travel time / expected arrival time of the recommended route is displayed (S2006).

  FIG. 9 shows an example of a map display of the recommended route.

  A recommended route 905 between the departure point 903 and the destination 904 is displayed on the map 909 so that the traffic level 906 in each traffic level display section can be identified. In FIG. 9, reference numeral 907 denotes an expected travel time (estimated arrival time) of the destination, reference numeral 908 denotes a reliability (estimated error) of the expected travel time (expected arrival time) 907, and reference numeral 911 denotes an expected travel time ( This is an information source of the traffic information statistical value used in the calculation of (expected arrival time) 907. Further, reference numeral 901 is a time display bar for accepting the designation of the departure time from the user, and a list of the departure times of each recommended route stored in the route storage unit 44 is displayed. The user can display the recommended route on the desired departure time on the display 2 by operating the cursor 902. For each traffic level display section, the estimated arrival time (estimated arrival time at the end node of the last link constituting the traffic level display section immediately before the traffic level display section) that reaches the traffic level display section Alternatively, it may be displayed in accordance with the start position of the congestion level display section on the map.

  FIG. 10 is a flowchart for explaining the map display processing of the recommended route in S2006 of FIG.

  First, the route search unit 42 notifies the menu display processing unit 50 of the departure place and the destination, and instructs the generation of the time display bar 901 shown in FIG. In response to this, the menu display processing unit 50 identifies the departure time of each recommended route of the same departure point 801 and destination 802 stored in the route storage unit 43, and a time display bar including these departure times. 901 is created (S3001).

  Next, the route search unit 42 notifies the map display processing unit 45 of the departure place and the destination and instructs the generation of the map 909 shown in FIG. In response to this, the map display processing unit 45 reads the first conversion table from the map / statistical traffic data storage device 3 via the data reading unit 48. Then, using the first conversion table, the mesh ID of at least one mesh constituting the area including the departure point 801 and the destination 802 stored in the route storage unit 43 is specified, and each having the specified mesh ID The mesh map data 31 is read from the map / statistical traffic data storage device 3 via the data reading unit 48. Then, a map 909 including the departure point 903 and the destination 904 is created based on the read map data 31 (S3002).

  Next, the route search unit 42 is stored in the route storage unit 43 in the menu display processing unit 50, such as the departure time specified by the user (the earliest departure time in the initial stage) received from the user operation analysis unit 41. A predetermined departure time of the departure times of each recommended route is notified, and generation of an expected travel time (expected arrival time) 907 and a reliability (estimated error) 908 shown in FIG. 9 is instructed. In response to this, the menu display processing unit 50 identifies information on the recommended route including the departure time notified from the route search unit 42 from the route storage unit 43, and the estimated travel time (expected arrival time) based on the information. ) And display contents of 907 and reliability (estimated error) 908 are created (S3003).

  Next, the route search unit 42 notifies the map display processing unit 45 of the departure time notified to the menu display processing unit 50 in S3003 and instructs the generation of the recommended route 905 shown in FIG. In response to this, the map display processing unit 50 stores each link constituting the recommended route based on the recommended route information including the departure time notified from the route search unit 42 and stored in the route storage unit 43. The traffic level of each traffic level display section is specified, and the display content of the recommended route 905 is created (S3004). In addition, the display contents of the traffic congestion level 906 are also created.

  The graphic processing unit 51 combines the display contents created by the menu display processing unit 50 and the map display processing unit 45 in S3001 to S3004 and displays a display screen as shown in FIG. 9 on the display 2 (S3005). ).

  Now, the user operation analysis part 41 detects whether the display position of the cursor 902 was operated by the user via the input device 5 or the voice input / output device 4 (S3006). If the display position of the cursor 902 is operated, the departure time indicated by the new display position is set to the departure time designated by the user, and the process returns to S3003.

  Next, the route guidance operation will be described.

  FIG. 11 is a flowchart for explaining the recommended route guidance operation of the in-vehicle navigation device to which the present embodiment is applied. In this flow, the user operation analysis unit 41 displays the current location, the point substantially the same as the current time, and the time that are currently displayed on the display 2 from the user via the voice input / output device 4 or the input device 5. The recommended route is started by receiving a route guidance request.

  First, the user operation analysis unit 41 notifies the route guidance unit 44 of the route guidance request received from the user. In response to this, the route guiding unit 44 starts measuring the travel time using a built-in timer (not shown) or the like (S4001). Further, the current location stored in the route storage unit 43, the same location as the current time, the information of the recommended route with the time as the departure location and the departure time, and the map data stored in the map / statistical traffic data storage device 3 Are used to start route guidance using a general (existing) route guidance technique (S4002).

  When the current location is newly output from the map match processing unit 47 during the route guidance process (S4003), the route guidance unit 44 sets a certain link (previous link) that constitutes the recommended route to be route guidance. It is determined whether or not it has moved to the next link (S4004). If it has not moved (No in S4004), the process returns to S4003 and waits for a new output of the current location from the map match processing unit 47.

  On the other hand, if it has moved (Yes in S4004), the route guiding unit 44 detects the travel time at that time and sets this as the actual measurement value of the travel time up to the previous link (S4005). Also, based on the information on the recommended route to be route guidance (traffic information statistical value) stored in the route storage unit 43, from the first link among the links constituting the recommended route to be route guidance. The total of the estimated travel time of each link up to the previous link is obtained (S4006).

  Then, the route guide unit 44 predicts the travel of each link up to the previous link obtained from the measured value of the travel time up to the previous link detected in S4005 and the recommended route information stored in the route storage unit 43 in S4006. A difference from the total time is obtained, and this difference is compared with the first and second predetermined values (S4007, S4008).

  Here, the second predetermined value is a value for determining the necessity of re-searching the recommended route to the destination. For example, A is the sum of the estimated travel times of each link to the previous link, and A is the recommended route. Is set to (A / B) × C, where B is the sum of the estimated travel time of each link constituting C and C is the estimated error of the estimated travel time to the destination. The first predetermined value is a value for determining the necessity of recalculation of the expected arrival time at the destination, and is a value smaller than the second predetermined value, for example, about 1/3 of the second predetermined value. Set to

  As described above, in the present embodiment, as the traffic information statistical value used for determining the link constituting the recommended route, the traffic information statistical value in the time zone including the expected arrival time at the start node of the link is used. (See S1008 in FIG. 6). Therefore, when the difference between the actual measured travel time up to the previous link and the sum of the estimated travel times of the links up to the previous link increases, each link after the previous link constituting the recommended route is determined. It is necessary to review the traffic information statistics used for this purpose. Therefore, in this embodiment, the difference is compared with the first and second predetermined values in S4007 and S4008.

  If the difference is smaller than the first predetermined value (No in S4007), the route guiding unit 44 returns to S4003 and waits for the current location to be newly output from the map match processing unit 47.

  If the difference is equal to or larger than the first predetermined value and smaller than the second predetermined value (Yes in S4007, No in S4008), the route guiding unit 44 determines the remaining link (the link next to the previous link). To the last link (each link from the destination link) is reset (S4009).

  Specifically, among the links constituting the recommended route, the link next to the immediately preceding link is the first link, and the last link (destination link) is the Mth link. The traffic information statistical value of the link associated with the same day type and weather type as the traffic information statistical value of the link stored in the route storage unit 43 as the traffic information statistical value of the first link Thus, the traffic information statistical value in the time zone including the current time is read from the map / statistical traffic data storage device 3 via the data reading unit 48. Then, the traffic information statistical value of the link stored in the route storage unit 43 is updated to the newly read traffic information statistical value. Further, the traffic information statistical value of the m-th (1 <m ≦ M) link is associated with the same day type and weather type as the statistical traffic information of the link stored in the route storage unit 43. Traffic information statistics of the link including the time of adding the total travel time obtained from the new traffic information statistics from the first link to the (m-1) th link at the current time. The value is read from the map / statistical traffic data storage device 3 via the data reading unit 48. Then, the traffic information statistical value of the link stored in the route storage unit 43 is updated to the newly read traffic information statistical value. This process is repeated until the traffic information statistical values of the second and subsequent links stored in the route storage unit 43 are updated.

  Then, the route guidance unit 44 recalculates the estimated arrival time of the destination using the traffic information statistics of the remaining links that have been reset, and outputs the result from the display 2 or the voice input / output device 4 to inform the user. (S4010). Here, the expected arrival time of the destination can be calculated by adding the total travel time obtained from the new traffic information statistics for each remaining link to the current time. Thereafter, the route guiding unit 44 returns to S4003 and waits for a new output of the current location from the map match processing unit 47.

  On the other hand, if the difference is greater than or equal to the second predetermined value (both Yes in S4007 and S4008), the route guidance unit 44 uses the current location and current time as the departure location and departure time, and determines the departure location, destination and current location. And set in the route search unit 42. Then, the route search unit 42 is caused to perform the above-described recommended route search process (see FIG. 6) (S4011). If a new recommended route is stored in the route storage unit 43, the process returns to S4001. Note that this flow ends when the current location reaches the destination.

  Next, a traffic congestion point display operation will be described.

  Here, the congestion point display operation is an operation for displaying the congestion level of each link constituting the road identified from the statistical traffic data stored in the map / statistical traffic data storage device 3 on the map. That is.

  FIG. 12 is a flowchart for explaining the congestion point display operation of the in-vehicle navigation device to which the present embodiment is applied. This flow is started when the user operation analysis unit 41 accepts a traffic jam point display request from the user via the voice input / output device 4 or the input device 5 while the map is displayed on the display 2.

  First, the user operation analysis unit 41 designates the day type (see 3221 in FIG. 3) and the weather type (see 3222 in FIG. 3) from the user via the voice input / output device 4 or the input device 5. Accept (S5001). Also, designation of a display mode for a traffic jam point is accepted (S5002).

  In the present embodiment, a graph showing the congestion level in each time zone of a representative link is displayed in a representative link display mode in which the link is displayed over the corresponding link display position on the map, and for each link by time zone. Any one of the time zone display modes for displaying the traffic level is accepted.

  If the designation of the display mode received from the user is the representative link display mode, the user operation analysis unit 41 sets the representative link display mode in the map display processing unit 45 as the congestion point display mode (S5003).

  In response to this, the map display processing unit 45 selects a representative link from the links constituting each road on the map displayed on the display 2 (S5101). The representative link may be a link including an intersection of a main road such as a national road. Whether or not the road constituting the link is a main road is determined by using road type information 3122 included in the link data 312. Whether or not an intersection of a main road is included is determined using connection link information 3126 included in the link data.

  Next, the map display processing unit 45 receives the statistical traffic data having the same mesh ID as the map data being displayed on the display 2 and stored in the map / statistical traffic data storage device 3 via the data reading unit 47. The statistical traffic information for each time zone of each representative link corresponding to the type of day and the type of weather designated in S5001 is obtained (S5102).

  Then, the map display processing unit 45 creates a graph indicating the congestion level in each time zone for each representative link using the information on the congestion level included in the obtained statistical traffic information (S5103). Then, the graphic processing unit 51 is requested to draw each created graph at the display position of the corresponding representative link. In response to this, the graphic processing unit 51 displays the corresponding graph superimposed on each representative link included in the map being displayed on the display 2 (S5104). If the user operation analysis unit 41 newly receives designation (change) of the congestion point display mode (Yes in S5105), the process returns to S5003.

  FIG. 13 shows a display example of a traffic jam point in the representative link display mode. In this example, a pie chart 915 showing the congestion level of each time zone of the representative link is displayed together with the information source 917 included in the statistical traffic information used to create this graph 915 and the corresponding representative link on the map. It is displayed near the display position (display position of the end node). The operator can grasp the traffic jam for each time zone of each main road from this graph. In addition, it is possible to know the information source of traffic jams for each main road time zone.

  On the other hand, in S5003, when the designation of the display mode received from the user is the display mode for each time zone, the user operation analysis unit 41 sets the display mode for each time zone as the display mode for the traffic jam point and the map display processing unit 45 and the menu display. Set in the processing unit 50. In response to this, the menu display processing unit 50 creates a time display bar including a plurality of time zones for designating the display time zone of the traffic jam information (S5201).

  Next, the map display processing unit 45 sets a display time zone for traffic jam information (S5202). When the user operation analysis unit 41 accepts designation of a time zone from the user in S5206 described later, this time zone is set as a traffic information display time zone. When the designation of the time zone is not received from the user, for example, a default time zone such as a time zone including the current time is set as the traffic information display time zone.

  Next, the map display processing unit 45 receives the statistical traffic data having the same mesh ID as the map data being displayed on the display 2 and stored in the map / statistical traffic data storage device 3 via the data reading unit 47. Statistical traffic information of each link corresponding to the day type and weather type specified in S5001 and the statistical traffic information of each link in the time zone set in S5202 is obtained (S5203).

  Then, the map display processing unit 45 creates a link image indicating the congestion level in the time zone set in S5202 for each link using the congestion level information included in the obtained statistical traffic information. (S5204). Then, the graphic processing unit 51 is requested to draw each of the created images so as to overlap the corresponding link. In response to this, the graphic processing unit 51 displays an image of the corresponding link superimposed on each link included in the map being displayed on the display 2 (S5205).

  Note that if the user operation analysis unit 41 newly accepts designation of the display time zone of the traffic jam information via the input device 5 or the voice input / output device 4 (S5206), the process returns to S5202. If the designation (change) of the display mode of the traffic jam point is newly accepted (Yes in S5207), the process returns to S5003.

  FIG. 14 shows a display example of a congestion point in the time zone display mode. In this example, each link 925 is displayed at the traffic congestion level in the time zone indicated by the cursor 902 in the time display bar 901. The operator can operate the cursor 902 via the input device 5 and the voice input / output device 4. The user operation analysis unit 41 notifies the map display processing unit 45 of the time zone indicated by the cursor 902 as the time zone specified by the user.

  The embodiment of the present invention has been described above.

  In the present embodiment, the map / statistical traffic data storage device 3 includes map data including link data of each link constituting a road on the map, and past data classified for each search condition that is a traffic information collection condition. And statistical data including travel time or moving speed of each link determined from the statistical value of the traffic information collected. The vehicle-mounted navigation device is configured such that the map data stored in the map / statistical traffic data storage device 3 and the type of day that is the search condition among the statistical data stored in the map / statistical traffic data storage device 3 and Using the statistical data corresponding to the type of weather, a recommended route between the departure point and the destination is searched. As described above, by using the statistical data of each link that matches the search condition, it is possible to search for a recommended route with the minimum cost (travel time) with high accuracy.

  Further, the statistical data has traffic information statistical values including travel time or moving speed for each time zone of each link constituting the road on the map. The in-vehicle navigation device uses the traffic information statistical value corresponding to the time zone including the departure time as the traffic information statistical value of the first link constituting the recommended route, and from among the links close to the departure place. Determine the first link. Further, as the traffic information statistical value of the nth (n ≧ 2) link constituting the recommended route, the total travel time determined from the traffic information statistical value of each of the first to n−1th links constituting the recommended route is The nth link is determined from the links connected to the (n−1) th link using the traffic information statistical value corresponding to the time zone including the time added to the departure time of the departure place. In this way, by changing the time zone of the traffic information statistic used to determine each link constituting the recommended route according to the estimated travel time from the departure place to the start node of each link, the minimum cost ( It is possible to search for a recommended route that is (travel time) with higher accuracy.

  In addition, the in-vehicle navigation system uses the actual travel time required from the departure point of the recommended route to the current location in the route guidance process, and the link that forms the section from the departure point of the recommended route to the current location. The travel time of the section obtained from the traffic information statistical value used for the determination is compared, and the necessity of re-searching for the recommended route is determined according to the comparison result. When it is determined that there is a need to re-search for the recommended route, the recommended route to the destination is re-searched using the current location as the departure location and the current time as the departure time. By doing so, it is possible to re-search for the recommended route so that the vehicle travels on the route with the minimum cost (travel time) even when traveling on the current recommended route during route guidance. .

  Further, the statistical data has a traffic information statistical value including the degree of congestion for each time zone of each link constituting the road on the map. Then, the in-vehicle navigation device has the time of each link specified by the statistical data corresponding to the collection condition specified by the user among the statistical data of each link included in the map data of the map displayed on the display 2. The congestion level for each band is displayed on the map. By doing in this way, it becomes possible to display the traffic congestion tendency on the road in more detail. In addition, it becomes easy to grasp changes in road congestion due to changes in time zones.

  In addition, this invention is not limited to said embodiment, A various deformation | transformation is possible within the range of the summary. For example, in the above embodiment, the search condition used for determining the traffic information statistical value used for cost calculation is not limited to the combination of the day type and the weather type. The type of day or the type of weather may be used alone as a search condition. Or you may make it manage a traffic information statistical value combining another condition with the kind of day and the kind of weather.

  In the above embodiment, an example in which the present invention is applied to a vehicle-mounted navigation device has been described. However, the present invention can also be applied to a navigation device other than a vehicle-mounted navigation device.

FIG. 1 is a schematic configuration diagram of an in-vehicle navigation device to which an embodiment of the present invention is applied. FIG. 2 is a diagram illustrating a configuration example of map data stored in the map / statistical traffic data storage device 3. FIG. 3 is a diagram illustrating a configuration example of statistical traffic data stored in the map / statistical traffic data storage device 3. FIG. 4 is a diagram illustrating a hardware configuration of the arithmetic processing unit 1. FIG. 5 is a diagram illustrating a functional configuration of the arithmetic processing unit 1. FIG. 6 is a flowchart for explaining the recommended route search operation of the in-vehicle navigation device to which the present embodiment is applied. FIG. 7 is a flowchart for explaining the recommended route display processing in S1018 of FIG. FIG. 8 is a diagram illustrating a graph display example of the recommended route on the display 2. FIG. 9 is a diagram illustrating a map display example of the recommended route on the display 2. FIG. 10 is a flowchart for explaining the map display processing of the recommended route in S2006 of FIG. FIG. 11 is a flowchart for explaining the recommended route guidance operation of the in-vehicle navigation device to which the present embodiment is applied. FIG. 12 is a flowchart for explaining the congestion point display operation of the in-vehicle navigation device to which the present embodiment is applied. FIG. 13 is a diagram illustrating an example of a traffic jam point display on the display 2 in the case of the representative link display mode. FIG. 14 is a diagram illustrating a traffic jam point display example on the display 2 in the time zone display mode. FIG. 15 is a diagram illustrating a configuration example of the second conversion table for specifying the day type from the date.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Arithmetic processing part, 2 ... Display, 3 ... Map / statistical traffic data storage device, 4 ... Voice output device, 5 ... Input device, 6 ... Wheel speed sensor, DESCRIPTION OF SYMBOLS 7 ... Geomagnetic sensor, 8 ... Gyro, 9 ... GPS receiver, 10 ... Weather information receiving device, 11 ... In-vehicle LAN device, 21 ... CPU, 22 ... RAM, 23 ... ROM, 24 ... DMA, 25 ... Drawing controller, 26 ... VRAM, 27 ... Color palette, 28 ... A / D converter, 29 ... SCI, 30. ··· PIO, 31 ... counter, 41 ... user operation analysis unit, 42 ... route search unit, 43 ... route storage unit, 44 ... route guidance unit, 45 ... map display processing 46, current position calculation unit, 47 map match processing unit, 48 ... data reading unit, 49 ... locus storing unit, 50 ... menu display processing unit, 51 ... graphics processing unit

Claims (15)

A navigation device route search method,
The navigation device includes map data including link data of each link constituting a road on the map, and each link determined by a statistical value of traffic information collected in the past, classified for each traffic information collection condition. A storage device for storing statistical data including travel time or travel speed;
A setup step to set the starting point, destination and collection conditions;
The map data stored in the storage device and the statistical data corresponding to the collection condition set in the setting step among the statistical data stored in the storage device are set in the setting step. A route search method for a navigation device, comprising: a route search step for searching for a route having the shortest travel time between a departure place and a destination as a recommended route. A navigation device route search method according to claim 1,
The statistical data has travel time or moving speed for each link time zone,
In the route search step, the travel time corresponding to the time zone including the departure time of the departure place included in the statistical data or the time zone as the travel time of each first candidate link constituting the recommended route N-1th candidate link connected to the nth candidate link as the travel time of each of the nth (n ≧ 2) candidate links constituting the recommended route A route search of a navigation device, wherein the recommended route is searched using a travel time corresponding to a time zone including an expected arrival time at an end node or a travel time obtained from a moving speed corresponding to the time zone. Method. A navigation device route search method according to claim 1,
A travel time calculating step for calculating a travel time or an estimated arrival time of the recommended route using a travel time of each link constituting the recommended route used for searching the recommended route in the route searching step;
A route search method for a navigation device, further comprising: a travel time display step for displaying a travel time or an estimated arrival time of the recommended route calculated in the travel time calculation step. A route search method for a navigation device according to claim 3,
The statistical data includes a degree of variation in traffic information that is a source of travel time or travel speed of each link,
In the travel time calculating step, the recommended time is calculated using a travel information or a variation degree of traffic information based on travel speed of each link constituting the recommended route used for searching the recommended route in the route searching step. Calculate the travel time error of the route,
The travel time display step displays a travel time or an estimated arrival time of the recommended route calculated in the travel time calculation step and an error thereof. A route search method for a navigation device according to claim 3,
The statistical data has a degree of congestion for each link time zone,
The travel time calculating step uses the congestion degree in a time zone corresponding to a travel time or a moving speed of each link constituting the recommended route used for searching the recommended route in the route searching step. When the route is divided into multiple sections, determine the degree of congestion for each section.
The travel time display step displays the travel time of the recommended route calculated in the travel time calculation step and the congestion degree of each section of the recommended route. A route search method for a navigation device according to claim 5,
The travel time display step displays each section of the recommended route in a bar graph shape with a length according to the travel time of the section and a display form according to the congestion degree of the section. Navigation device route search method. A route search method for a navigation device according to claim 6,
The route search step searches for a recommended route between the departure place and the destination for each of a plurality of departure times,
The travel time calculating step calculates a travel time and a congestion degree of each section of the recommended route for each recommended route for each of the plurality of departure times searched in the route search step,
In the travel time display step, for each recommended route for each of the plurality of departure times searched in the route search step, each section of the recommended route is displayed in the form of a bar graph. Method. A route search method for a navigation device according to claim 5,
The route search method for a navigation device, wherein the travel time display step displays each section of the recommended route on a map in a display form corresponding to the congestion degree of the section. A route search method for a navigation device according to any one of claims 2 to 8,
The navigation device has a current location calculation function,
Using the recommended route searched in the route search step and the current location calculated by the current location calculation function, a route guidance step of performing route guidance to the destination;
A travel time of a section from the current location calculated by the current location calculation function on the recommended route to the destination is calculated, and an expected arrival time correction step of correcting an expected arrival time of the destination is further performed,
The predicted arrival time correction step corresponds to a time zone including a current time included in the statistical data as a travel time of a first link constituting a section from the current location to the destination on the recommended route. As the travel time of each of the mth (m ≧ 2) links constituting the section from the current location to the destination on the recommended route, using the travel time obtained from the travel time or the travel speed corresponding to the time zone , Using the travel time corresponding to the time zone including the time obtained by adding the total travel time from the first link to the (m-1) -th link to the current time or the travel time obtained from the travel speed corresponding to the time zone. , Calculating the travel time of the section from the current location to the destination on the recommended route, and adding the travel time of the section to the current time, Route searching method of the navigation system and obtains the time. A route search method for a navigation device according to any one of claims 2 to 8,
The navigation device has a current location calculation function,
Using the recommended route searched in the route search step and the current location calculated by the current location calculation function, a route guidance step of performing route guidance to the destination;
The recommendation obtained from the actual travel time of the section on the recommended route from the departure location to the current location calculated by the current location calculation function and the travel time of each link constituting the recommended route used for searching the recommended route A re-search determination step of comparing the travel time of the section on the route and determining the necessity of re-searching the recommended route according to the comparison result,
The route search step uses the current location calculated by the current location calculation function as a departure location and the current time as a departure time when the re-search determination step determines that there is a need to re-search for a recommended route. A route search method for a navigation device, characterized by re-searching a recommended route to a destination set in steps. A storage device for storing map data including link data of each link constituting a road on the map, and statistical data including travel time or moving speed of each link determined from statistical values of traffic information collected in the past; ,
Setting means for setting the starting point and destination of the route to be searched;
Using map data and statistical data stored in the storage device, route search means for searching for a recommended route between the starting point and the destination set by the setting means,
The storage device stores the statistical data for each traffic information collection condition that is a source of the statistical data,
The setting means sets the collection conditions together with the starting point and the destination,
The route search means uses the map data stored in the storage device and the statistical data corresponding to the collection conditions set by the setting means to determine the route with the shortest travel time between the departure point and the destination. A navigation device characterized by searching as a recommended route. A traffic information display method for a navigation device,
The navigation device includes map data including link data of each link constituting a road on the map, and each link determined by a statistical value of traffic information collected in the past, classified for each traffic information collection condition. And a storage device for storing statistical data indicating the degree of congestion for each time zone,
A setting step to set the collection conditions;
Of the statistical data of each link included in the map data of the map displayed on the display device, a reading step of reading out statistical data corresponding to the collection condition set in the setting step from the storage device;
A traffic information display step of displaying the degree of congestion for each time zone of each link specified by the read statistical data in a superimposed manner on a map displayed on the display device. Traffic information display method. A traffic information display method for a navigation device according to claim 12,
The traffic information display method of the navigation device, wherein the traffic information display step displays a graph indicating a degree of congestion for each predetermined time zone of the link so as to overlap the position of the link on a map. A traffic information display method for a navigation device according to claim 12,
A reception step for accepting designation of the time zone from the operator is further performed,
The traffic information display step displays the links constituting the road on the map to be displayed so that the degree of congestion in the time zone received in the reception step can be identified. Method. Map data including the link data of each link constituting the road on the map, and each traffic information collection condition that indicates the degree of congestion for each link time zone determined from the statistics of traffic information collected in the past A storage device for storing statistical data classified into
A setting means for setting the collection conditions;
Reading means for reading, from the storage device, statistical data corresponding to the collection condition set in the setting step among statistical data of each link included in the map data of the map displayed on the display device;
And a traffic information display means for displaying the degree of traffic jam of each link specified by the statistical data read by the reading means on a map displayed on the display device. apparatus.

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