JP2006153693A - Navigation system and route guidance method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a route guide capable of efficiently avoiding congestions, in a navigation system. <P>SOLUTION: This navigation system/route guide method is provided with a storage device 3 for storing link information correlated with information, indicating road classification of a link in each of the links in the navigation system for searching a recommended route up to a destination; and an arithmetic processing part 1 having a means for detecting the present position; a means of receiving, from an outside, road traffic information including information specifying at least the link under the congestion; a means of determining the presence of the link under the congestion in the recommended route, using the searched recommended route and the received road traffic information, and of searching a by-pass route toward the destination by by-passing the link under the congestion, when the link under the congestion exists, and a determination means for extracting a branch point branching the by-pass route from the recommended route; and for determining the propriety of adopting the by-pass route, based on the road classification of the link in the recommended route advancing into the extracted branch point, that is the link connected to the branch point. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a navigation device, and more particularly to a route search and route guidance technique for an in-vehicle navigation device.

  2. Description of the Related Art Conventionally, navigation devices that receive road congestion information and search for a detour route that bypasses the congested road using the received traffic congestion information are known (for example, Patent Documents). 1). The navigation device of Patent Document 1 searches for a recommended route to a destination according to a request from the user, and performs route guidance for the user using the searched recommended route. Moreover, the navigation apparatus of patent document 1 determines whether the traffic jam road which the received traffic jam information shows is a road which comprises a recommended route. The navigation device searches for a detour that avoids a congested road and presents the detour to the user when the congested road indicated by the congested information is a road that constitutes a recommended route.

Japanese Patent Laid-Open No. 9-318377

  By the way, when driving on a highway and getting involved in a traffic jam, the driver and passengers often want to get out of the traffic as soon as possible. This is because there are no rest areas or stores on the highway. Further, when searching for a detour from an expressway, the navigation device often searches for a route that returns to the original expressway immediately after getting off the expressway as a detour. Such a route is not an appropriate route as a detour for avoiding traffic jams.

  However, in Patent Document 1, no particular consideration is given to obtaining a detour from an expressway. In Patent Document 1, when the recommended route is an expressway, no detour is searched. Therefore, in Patent Document 1, depending on the road type of the recommended route, it may not be possible to guide a route that avoids congestion.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide route guidance capable of efficiently avoiding traffic jams in a navigation device.

  In order to solve the above-described problem, according to one aspect of the present invention, a recommended route from a departure place to a destination is searched using link information included in map data, and a route to a user is searched using the searched recommended route. It is applied to a navigation device that provides guidance. The link information includes road type information indicating whether the link is an expressway, a dedicated road, or a general road for each link.

  Then, the navigation device receives from the outside means for storing the searched recommended route, means for detecting the current position, and road traffic information including at least information for identifying a congested link. Means, the stored recommended route, the received road traffic information, and the detected current position, there is a traffic jam included in the road traffic information in the recommended route from the current position to the destination Means for determining whether or not there is a link, and when there is a congested link, bypassing the congested link and searching for a detour from the current position to the destination; Using the stored recommended route, the searched detour, and the link information, means for determining whether or not to adopt the detour, and using the detour when it is determined to adopt Sutra Means for performing route guidance using the stored recommended route when it is not determined to be adopted, and the means for determining branches between the recommended route and the detour A branch point to be extracted, a link of a recommended route entering the extracted branch point, and a link connected to the branch point is specified, and the detour according to a condition defined for each road type of the specified link It is determined whether or not to adopt.

  As described above, according to the present invention, when there is a congested road on the recommended route, and when searching for a detour, the detour searched in consideration of the type of road of the recommended route that is running is adopted. Whether or not is determined. Therefore, according to the present invention, it is possible to efficiently cope with traffic jams.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, a schematic configuration of an in-vehicle navigation device to which an embodiment of the present invention is applied will be described with reference to FIG.

  FIG. 1 is a schematic configuration diagram of an in-vehicle navigation device (hereinafter simply referred to as “navigation device”) to which an embodiment of the present invention is applied.

  As shown in the figure, the navigation device includes an arithmetic processing unit 1, a display 2, a storage device 3 in which map data and the like are stored, a voice input / output device 4, an input device 5, a wheel speed sensor 6, and a geomagnetism. A sensor 7, a gyro 8, a GPS (Global Positioning System) receiver 9, and an FM multiplex broadcast receiver 10 for receiving road traffic information transmitted by a center or the like that provides a road traffic information providing service.

  The arithmetic processing unit 1 is a central unit for processing various types of information provided to the user by the navigation device. For example, the current position is detected based on information output from the various sensors 6 to 8 and the GPS receiver 9. The arithmetic processing unit 1 reads map data around the detected current position from the storage device 3, develops the read map data in graphics, and displays a mark indicating the current position on the display 2 in an overlapping manner. In addition, the arithmetic processing unit 1 searches for a recommended route connecting the current position and the destination instructed by the user, and guides the user using the voice input / output device 4 and the display 2. Further, the arithmetic processing unit 1 determines whether or not the recommended route searched using the road traffic information received by the FM multiplex broadcast receiving apparatus 10 is congested. If the arithmetic processing unit 1 determines that there is a traffic jam, the arithmetic processing unit 1 searches for a detour to avoid the traffic jam. Further, the arithmetic processing unit 1 determines whether or not to use the searched detour in accordance with a predetermined requirement to be described later. If it is determined that the detour is to be used, the calculated detour is displayed on the display 2. And follow the detour to guide the route.

  The display 2 is a unit that displays the image data generated by the arithmetic processing unit 1 and includes 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 TV Standards Committee) signal.

  The storage device 3 is a unit that stores data such as map data corresponding to a multi-stage scale map from an overall view of the Japanese archipelago to detailed views of municipalities throughout the country. As the storage device 3, for example, a DVD device or a hard disk device can be used.

  Here, the structure of the map data will be described.

  FIG. 2 is a diagram schematically showing the data structure of map data stored in the storage device 3 according to the embodiment of the present invention.

  As shown in the drawing, the map data 310 is classified for each mesh region obtained by dividing the map into a plurality of parts. The map data 310 includes a mesh ID 311 for identifying a mesh area, and link data 312 of each link constituting a road included in the mesh area.

  The link data 312 includes a link ID 3121 for identifying a link, coordinate information 3122 of two nodes (start node and end node) constituting the link, the road to which the link belongs is “highway”, “exclusive road”, and “ Road type 3123 indicating whether it is a “general road”, link length information 3124 indicating link length, link travel time (or travel time) information 3125, and two nodes (start node and end node) Each has a link ID (connection link ID) 3126 of the link to be connected.

  In addition to the map data described above, the storage device 3 has a table (referred to as a conversion table) for specifying a mesh ID of a mesh region including a point specified by the coordinate information from the coordinate information. It is remembered.

  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, recognizes the voice uttered by the user, and transfers the recognized content to the arithmetic processing unit 1. To do.

  The input device 5 is a unit that receives instructions from the user for selecting various functions of the navigation device, setting a destination, and the like. Hard switches such as a scroll key and a scale change key, Joystick, a touch panel pasted on the display 2 Consists of.

  The sensors 6 to 8 and the GPS receiver 9 are used by the navigation device to detect the current position. The wheel speed sensor 6 measures the distance from the circumference of the wheel and the measured rotational speed of the wheel, and further measures the angle at which the moving body is bent from the rotational speed of the paired wheel. The geomagnetic sensor 7 detects the magnetism held by the earth and detects the direction in which the moving body is heading. The gyro 8 is composed of an optical fiber gyro and a vibration gyro, 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 GSP satellite and the change rate of the distance with respect to three or more satellites, thereby moving the mobile body's current position, traveling direction, and traveling Measure orientation.

  Next, functions of the arithmetic processing unit 1 of the navigation device described above will be described with reference to FIG.

  FIG. 3 is a diagram for explaining a functional configuration of the arithmetic processing unit 1 according to the embodiment of the present invention.

  As illustrated, the arithmetic processing unit 1 includes a setting unit 20, a current position detection unit 11, a data reading unit 12, a map match processing unit 13, a route search unit 14, a route guidance unit 15, a map display processing unit 16, and graphics. A processing unit 17, a traffic data update unit 18, and a route / traffic data storage unit 19 are included.

  The setting unit 20 receives a request from a user input to the input device 5 or the voice input / output device 4, and controls the arithmetic processing unit 1 so that processing corresponding to the requested content is executed. For example, when the user requests a search for a recommended route to go to the destination via the input device 5, the user requests the route search unit 14 to search for a recommended route from the current position to the destination.

  The current position detection unit 11 uses the distance data and the angle data obtained as a result of integrating the distance pulse data S5 measured by the wheel speed sensor 6 and the angular velocity data S7 measured by the gyro sensor 8, respectively. By integrating with the shaft, the current position (X ′, Y ′), which is the position after the vehicle travels, is periodically calculated from the initial value (X, Y). The current position detection unit 11 outputs the calculated current position to the map display processing unit 16 and outputs the calculated current position to the map match processing unit 13 every predetermined number of calculations. When the current position detection unit 11 acquires correction data for the current position from the map match processing unit 13 described later, the current position detection unit 11 outputs the correction data for the current position to the map display processing unit 16. Further, when the current position is requested from the route guidance unit 15, the current position detection unit 11 outputs the current position (or correction data for the current position) to the route guidance unit 15.

  Here, the current position detection unit 11 integrates the azimuth data S6 obtained from the geomagnetic sensor 7 and the angular velocity data S7 obtained from the gyro 8 in order to match the relationship between the rotation angle of the host vehicle and the traveling direction. With reference to the angle data, the absolute direction of the direction in which the vehicle is traveling is estimated. As the current position detector 11 integrates the data S5 of the wheel speed sensor 6 and the data S7 of the gyro 8 respectively, errors accumulate, so that the position data S8 obtained from the GPS receiver 9 in a certain time is also stored. A process for canceling the accumulated error is performed to obtain data on the current position.

  The data reading unit 12 reads, from the storage device 3, map data in an area requested to be displayed on the display 2 or an area required for route search (including the current position and destination).

  The map match processing unit 13 performs map match processing for combining the map data around the current position read by the data reading unit 12 and the current position periodically detected by the current position detection unit 11. The map match processing unit 13 periodically corrects the current position and outputs data indicating the corrected current position to the current position detection unit 11.

  The traffic data update unit 18 receives the road traffic information received by the FM multiplex broadcast receiver 10. In this embodiment, the specific configuration of the road traffic information is not particularly limited, but the road traffic information includes at least information on the date and time when the traffic jam occurred and the link where the traffic jam occurs. (Link ID) is included. Then, the traffic data update unit 18 stores the received road traffic information in the route / traffic data storage unit 19 in association with the received date and time. Further, the traffic data update unit 18 updates the road traffic information stored in the route / traffic data storage unit 19 at a predetermined interval. Specifically, the traffic data update unit 18 searches the stored road traffic information for a traffic jam occurring date and time when a predetermined time or more has elapsed from the current date and time. The road traffic information that has passed more than the time is erased (information that has passed a predetermined time or more from the received date and time may be erased).

  The traffic data updating unit 18 may store only the road traffic information of roads within a predetermined range from the links constituting the recommended route from the received road traffic information in the route / traffic data storage unit 19. Good.

  The route / traffic data storage unit 19 stores the above-described road traffic information and data indicating the recommended route searched by the route search unit 14.

  The route search unit 14 uses the Dijkstra method or the like to search for a route that reaches the destination at an optimal cost connecting the two specified points (current position, destination) using the link data 312 (see FIG. 2). To do. In addition, the route search unit 14 searches for a detour when receiving a detour search request from the route guidance unit 15 described later, and performs a process of determining whether or not to adopt the detour. The process for searching for a detour and the process for determining whether or not to use the searched detour will be described in detail later.

  The route search unit 14 outputs data indicating the recommended route to the map display processing unit 16 in order to display the route obtained as a result of the search as a recommended route on the display 2. Further, the route search unit 14 outputs data indicating the searched recommended route to the route guidance unit 15. The route search unit 14 stores the recommended route obtained as a result of the search in the route / traffic data storage unit 19. When the route search unit 14 determines that the searched detour is adopted as a result of the detour determination processing (FIG. 6) described later, the route search unit 14 displays data indicating the detour as a map display processing unit 16 and a route guide unit. 15 is output.

  The route guidance unit 15 guides the user so as to reach the destination through the searched recommended route. In addition, the route guidance unit 15 determines whether or not there is a congested road on the recommended route at a predetermined interval (determines whether or not a congested road is included). Processing will be described later). The route guidance unit 15 sends a detour search request to the route search unit 14 when there is a congested road on the recommended route. In response to the detour search request, when the route search unit 14 transmits information indicating the detour, the route guidance unit 15 receives the transmitted detour information and uses the detour. Guide users to their destination. The route guidance unit 14 continues the route guidance using the recommended route when there is no congested road on the recommended route and when no detour is received from the route search unit 14.

  The map display processing unit 16 receives the map data 310 in the area requested to be displayed on the display 2 from the storage device 3 via the data reading unit 12. The map display processing unit 16 receives the recommended route searched for from the route search unit 14 (a detour when there is a detour), and receives information on the current position from the current position detection unit 11. Then, the map display processing unit 16 generates a map drawing command for drawing a road, other map components, a current position, a destination, and a mark such as an arrow for route guidance on the screen of the display 2, The result is output to the graphics processing unit 17.

  The graphics processing unit 17 displays image data on the screen of the display 2 using the map drawing command generated by the map display processing unit 16.

  Next, the hardware configuration of the arithmetic processing unit 1 according to the present embodiment will be described.

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

  As shown in the figure, the arithmetic processing unit 1 includes a CPU (central processing unit) 21, a RAM (Random Access Memory) 22 that temporarily stores programs and data executed by the CPU 21, and the above-described units (setting unit 20, The functions of the current position detection unit 11, data reading unit 12, map match processing unit 13, route search unit 14, route guidance unit 15, map display processing unit 16, graphics processing unit 17, and traffic data update unit 18) A ROM (Read Only Memory) 23 in which a program to be executed is stored in advance, a DMA (Direct Memory Access) 24 for transferring data between the memories and between the memory and each device, graphic drawing and A drawing controller 25 that performs display control, a video random access memory (VRAM) 26 that stores graphics image data, and an image A color palette 27 that converts data into RGB signals, an A / D converter 28 that converts analog signals into digital signals, an SCI (Serial Communication Interface) 29 that converts serial signals into parallel signals synchronized with the bus, and parallel A PIO (Parallel Input / Output) 30 that puts a signal on the bus in synchronization with the bus and a counter 31 that integrates the pulse signal are included. And each said part (setting part 20, current position detection part 11, data reading part 12, map matching processing part 13, route searching part 14, route guidance part 15, map display processing part 16, graphics processing part 17, traffic data The function of the update unit 18) is realized by the CPU 21 loading a program for executing the function of each unit stored in the ROM 23 into the RAM 22 and executing it. The route / traffic data storage unit 19 is provided in a predetermined area of the RAM 22.

  Next, route search processing and route guidance processing performed by the navigation device of this embodiment will be described.

  FIG. 5 is a flowchart of route search processing and route guidance processing performed by the navigation device of this embodiment. The route / traffic data storage unit 19 of the navigation device is assumed to store road traffic information. That is, the traffic data update unit 18 receives the road traffic information received by the FM multiplex broadcast receiving apparatus 10 and stores the received traffic information in the route / traffic data storage unit 19. Further, as described above, the traffic data update unit 18 updates the road traffic information stored in the route / traffic data storage unit 19 at predetermined intervals.

  First, the route search unit 14 searches for a recommended route to the destination (S100). Specifically, the route search unit 14 receives an input of a destination from the user via the setting unit 20. In addition, the route search unit 14 acquires the current position of the vehicle via the current position detection unit 11. In the following description, the case where the current position of the vehicle is the departure point is taken as an example, but the present invention is not particularly limited thereto. The route search unit 14 may accept an input of a departure place from the user via the setting unit 20. Then, the route search unit 14 reads the conversion table from the storage device 3 and specifies the mesh ID of the mesh region including the point specified by the coordinate information from the coordinate information indicating the current position and the destination. Next, the route search unit 14 obtains each link data 312 registered in each map data having the identified mesh ID from the storage device 3 via the data reading unit 12. The route search unit 14 uses the obtained link data 312 to search for a recommended route to reach the destination at an optimal cost, and outputs data indicating the searched recommended route to the route guidance unit 15.

  The route guidance unit 15 receives the recommended route output by the route search unit 14 and starts route guidance for the user (S101). Specifically, the route guidance unit 15 acquires the recommended route output by the route search unit 14. Further, the current position is periodically acquired from the vehicle position detection unit 11. Then, the route guidance unit 15 uses the acquired current position, the data indicating the recommended route acquired from the route search unit 14, and the map data read from the storage device 3 via the data reading unit 12. To the destination. The route guidance unit 15 compares the received recommended route information with the current position acquired from the current position detection unit 11, and determines whether the vehicle should go straight or turn right or left before passing the intersection or the like. The user is notified by voice or the direction to be advanced is displayed on the map displayed on the display 2 to notify the user of the recommended route.

  In addition, the route guidance unit 15 determines whether there is a congested road on the recommended route from the current position to the destination at a predetermined interval (S102). Specifically, the route guidance unit 15 reads the traffic information stored in the route / traffic data storage unit 19. The route guidance unit 15 is information that identifies the current position acquired from the current position detection unit 11, the link that constitutes the recommended route acquired in S101, and the link in which the traffic congestion included in the read road traffic information has occurred. (Link ID) is used to determine whether there is a congested link included in the road traffic information in the recommended route from the current position to the destination. If there is a link indicating that there is a traffic jam on the recommended route from the current position to the destination, the route guidance unit 15 sends a detour search request to the route search unit 14 and proceeds to the processing of S103. . If the route guidance unit 15 determines that there is no congested road on the recommended route, the route guidance unit 15 proceeds to the process of S107. Note that the detour search request includes data indicating a link constituting a recommended route and data indicating a congested link on the recommended route.

  In S103, the route search unit 14 receives a detour search request from the route guide unit 15 and searches for a detour. The search for a detour in this step is realized by the conventional technique. For example, the route search unit 14 acquires the current position from the current position detection unit 11, and uses the current position, the data indicating the recommended route included in the detour search request, and the data indicating the congested link, as a detour. The mesh ID of the mesh area necessary for the search is specified. Then, the route search unit 14 obtains each link data 312 registered in each map data having the identified mesh ID from the storage device 3 via the data reading unit 12. The route search unit 14 uses the acquired link data 312 to search for a detour that bypasses a congested link on the recommended route and reaches the destination.

  Subsequently, the route search unit 14 performs a process of determining whether or not to adopt the detour searched in S103 (S104). If it is determined that the detour is to be adopted, data indicating the detour (the detour) Link data) is output to the route guidance unit 15, and the process proceeds to S106. On the other hand, if it is determined that the detour is not adopted, the route search unit 14 outputs information indicating that fact to the route guidance unit 15 and proceeds to S107.

  In S <b> 106, the route guidance unit 15 receives data indicating the detour route output from the route search unit 14, and displays the received data indicating the detour route on the display 2 via the display processing unit 16. In addition, the route guidance unit 15 guides the user to the destination using the adopted detour as a new recommended route. Specifically, the route guidance unit 15 compares the data indicating the accepted detour and the current position acquired from the current position detection unit 11, and should it go straight ahead or turn right or left before passing an intersection or the like? The voice input / output device 4 is used to notify the user by voice, or the direction to be advanced is displayed on the map displayed on the display 2, and the route guidance for the user is performed using the detour as the recommended route.

  Next, the process of S107 that proceeds when it is determined in S102 that there is no congested road on the recommended route and when it is determined that a bypass is not adopted in S105 will be described. In S107, the route guidance unit 15 provides route guidance to the user according to the recommended route searched in S100, and proceeds to S108.

  In S108, the route guidance unit 15 determines whether or not the current position has reached the destination by using the current position detected by the current position detection unit 11, and returns to S102 if the current position has not been reached. If so, the process ends. Note that the route guidance unit 15 may return to the processing of S102 to S107 when performing route guidance using a detour. In this case, in the processes of S102 to S107, the presence / absence of traffic congestion, search for a detour, detour determination processing, and the like are performed using the adopted detour as a recommended route.

  Next, the detour determination process in S104 will be described with reference to FIGS. FIG. 6 is a flowchart of the detour determination processing according to the present embodiment. FIG. 7 is a diagram illustrating recommended routes and detours. In the example of FIG. 7, links 1000, 1001, 1002, 1003, and 1004 are recommended routes, and links 1000, 1200, 1201, 1003, and 1004 are detours.

  First, the route search unit 14 extracts a branch point 1100 (see FIG. 7) between the recommended route and the detour using the recommended route acquired in S103 and the searched detour (S200).

  Subsequently, the route search unit 14 is a link on the recommended route connected to the extracted branch point, and the link (link 1000 in the example of FIG. 7) entering the branch point is an expressway (or a dedicated road). ) Is determined (S201). If the route search unit 14 determines that the road is a highway (or exclusive road) as a result of the determination, the process proceeds to S202. If the route search unit 14 determines that the road is not a highway (or exclusive road), the process proceeds to S206. Proceed to processing. Specifically, the route search unit 14 specifies a link that is connected to the extracted branch point and is common to both the detour and the recommended route, and is specified using the link data 312. The road type is determined (see FIG. 2).

  In S202, the route search unit 14 determines whether or not there is a merging point between the detour and the recommended route. If there is a merging point, the process proceeds to S203, and if there is no merging point, the process proceeds to S206. Proceed to processing. Specifically, the route search unit 14 is a link that constitutes a detour, and there is no link having a link ID 3121 common to the recommended route among the links that constitute the route after branching from the recommended route. It is determined that there is no confluence. On the other hand, the route search unit 14 determines that there is a confluence when there is a link that forms a detour and has a link ID 3121 that is common to the recommended route among the links after branching from the recommended route. To do. For example, in the case of FIG. 7, it is determined that there is a confluence 1101.

  In S203, the route search unit 14 extracts a merging point, and specifies a link connected ahead of the merging point (1101 in the example of FIG. 7) (link 1003 in the example of FIG. 7). More specifically, the route search unit 14 specifies a link that is connected to the junction and has a link ID 3121 common to both the detour and the recommended route. Then, the route search unit 14 determines whether or not the identified link is an expressway (or a dedicated road) according to the same procedure as S201. If the route search unit 14 determines that the road is an expressway (or exclusive road) as a result of the determination, the process proceeds to S204. If the route search unit 14 determines that the road is not an expressway (or exclusive road), the process proceeds to S206. Proceed to processing.

  In S204, the route search unit 14 obtains the distance from the branch point to the merge point using the recommended route, the link data 312, and the extracted branch point and merge point. Specifically, the route guiding unit 14 specifies links (links 1001 and 1002 in the example of FIG. 7) on the recommended route from the branch point to the junction. The route guiding unit 14 obtains the distance from the branch point to the merge point from the link length information 3124 (see FIG. 2) of the link data 312 of the identified link. The route guiding unit 14 proceeds to the process of S205 when the obtained distance is shorter than a predetermined distance (for example, 1 km), and proceeds to the process of S206 when longer than the predetermined distance.

  In S205, the route search unit 14 determines that the detour is not adopted. That is, in this embodiment, the route search unit 14 is a case where the branch point between the recommended route and the detour is an expressway, and the detour and the recommended route are merged after being branched, and merged In the case where the subsequent road is an expressway, when the distance on the recommended route from the junction to the junction is shorter than a predetermined distance, the detour is not adopted. By configuring in this way, for example, when the recommended route is an expressway, it is possible to prevent the use of a detour that returns from the expressway and immediately returns to the expressway.

  On the other hand, in S206, the route search unit 14 determines to adopt a detour. That is, the navigation device of the present embodiment employs a detour when the road before branching is not an expressway (or a dedicated road). This is because, in the case of a general road, it is considered that there is a high possibility that it is a reasonable detour even if it is a detour that immediately returns to the recommended route. In addition, the navigation device according to the present embodiment employs a detour when the pre-branch road is an expressway (or a dedicated road) and the detour does not merge with the recommended route after branching. Further, when the road before the branch is an expressway (or a dedicated road) and the road after the merge is an expressway, a detour is adopted. This is because the detour is considered appropriate in such a case.

  Further, the navigation device of the present embodiment is a case where the branch point between the recommended route and the detour is a highway, and when the detour and the recommended route branch and merge, and the road after the merge When is a highway, if the distance on the recommended route from the junction to the junction is longer than a predetermined distance, a detour is adopted. For example, when the recommended route is an expressway, the distance from the junction to the junction is longer than the predetermined distance even if the recommended route is a detour that returns from the expressway to the expressway. This is because it is considered that the detour is appropriate when it is far away.

  As described above, according to the present invention, when there is a congested road on the recommended route, and when searching for a detour, considering the type of road before branching between the recommended route and the detour, Employment conditions for whether or not to use a detour are defined. Then, it is determined whether to adopt a detour according to the employment conditions. Therefore, in this embodiment, when the searched detour is valid, route guidance is performed according to the detour, and when the searched detour is not valid, route guidance is performed according to the original recommended route instead of the detour. It can be carried out.

  Therefore, according to the present invention, it is possible to perform route guidance that efficiently copes with traffic congestion.

  The present invention is not limited to the embodiment described above, and various modifications can be made within the scope of the gist of the present invention. For example, in the present embodiment, the detour is determined using the received road traffic information, but the present invention is not limited to this. For example, the user may directly input information on a road to be bypassed into the navigation device, and the navigation device may search for a detour using the input information on the road to be bypassed. Then, the navigation device may perform the processing steps shown in FIG. 6 and determine whether or not to use the searched detour.

  In the above description of the embodiment, an example has been described in which it is determined whether or not the recommended route is congested at a predetermined interval. However, the present invention is not particularly limited to this. For example, each time the FM multiplex broadcast receiving apparatus 10 receives road traffic information, it may be determined whether the recommended route is congested. Further, when a request from the user is accepted, it may be determined whether or not the recommended route is congested.

  In the description of the above embodiment, the highway (or exclusive road) and the general road are used as the road type information, but the present invention is not limited to this. The road type information may be further classified (prefectural roads, narrow streets, etc.), and conditions for determining whether or not to adopt a detour for each classified road type information may be determined.

1 is a schematic configuration diagram of an in-vehicle navigation device to which an embodiment of the present invention is applied. It is a figure which shows the data structure of the map data memorize | stored in the memory | storage device 3 of embodiment of this invention in simulation. It is a figure for demonstrating the function structure of the arithmetic processing part 1 of embodiment of this invention. It is a figure which shows the hardware constitutions of the arithmetic processing part 1 of embodiment of this invention. It is a figure for demonstrating the flow of the route search process and route guidance process which the navigation apparatus of embodiment of this invention performs. It is a flowchart of the detour determination process which the navigation apparatus of embodiment of this invention performs. It is the figure which illustrated the recommendation course and detour of the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Arithmetic processing part, 2 ... Display, 3 ... Memory | storage device, 4 ... Voice input / output device, 5 ... Input device, 6 ... Wheel speed sensor, 7 ... Geomagnetic sensor, 8 ... Gyro, 9 ... GPS receiver, 10 ... FM multiplex broadcast receiver, 11 ... current position detection unit, 12 ... data reading unit, 13 ... map match processing unit, 14 ... route search unit, 15 ... route guidance unit, 16 ... map display processing unit, 17 ... graphics processing , 18 ... traffic data update unit, 19 ... route / traffic data storage unit, 20 ... setting unit, 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

Claims (4)

A navigation device that searches for a recommended route from a starting point to a destination using link information included in map data, and performs route guidance for a user using the searched recommended route,
The link information includes, for each link, road type information indicating whether the link is a highway, a dedicated road, or a general road,
Means for storing the searched recommended route;
Means for detecting the current position;
Means for receiving road traffic information including information identifying at least a congested link from outside,
Using the stored recommended route, the received road traffic information, and the detected current position, there is a congested link included in the road traffic information in the recommended route from the current position to the destination. Means for searching for a detour from the current position to the destination, bypassing the congested link when there is a congested link;
Means for determining whether to adopt the detour using the stored recommended route, the searched detour, and the link information;
Means for performing route guidance using the detour when it is determined to be adopted, and performing route guidance using the stored recommended route when it is not determined to be adopted,
The means for determining is
A branch point where the recommended route and the detour route branch is extracted, a link of a recommended route entering the extracted branch point, and a link connected to the branch point is specified, and the road type of the specified link A navigation device characterized by determining whether or not to adopt the detour according to a condition defined for each. The navigation device according to claim 1,
The means for determining is
When the link connecting to the specified branch point is a general road, adopt the detour,
If the link connecting to the specified branch point is either a highway or a dedicated road, determine whether or not the detour and the recommended route merge after the branch,
When not joining, adopt the detour, and when joining, find the recommended route and the junction with the detour,
A link that is common to both the detour and the recommended route and that is connected to the junction point is specified, and the detour is performed according to a condition determined for each road type of the link that connects to the specified junction point. A navigation device characterized by determining whether or not to adopt a road. The navigation device according to claim 2,
The means for determining is
When the link connecting to the identified junction is a general road, adopt the detour,
When the link connecting to the specified junction is either an expressway or a dedicated road, the distance between the branch point and the junction is calculated, and when the calculated distance is greater than a predetermined distance, a detour is adopted. A navigation apparatus characterized by not adopting a bypass when the distance is smaller than the predetermined distance. A route guidance method performed by a navigation device that searches for a recommended route from a departure point to a destination using link information included in map data, and performs route guidance for a user using the searched recommended route. ,
The link information includes, for each link, road type information indicating whether the link is a highway, a dedicated road, or a general road,
The navigation device
Detecting the current position;
Receiving road traffic information including information identifying at least a congested link from outside,
Using the stored recommended route, the received road traffic information, and the detected current position, there is a congested link included in the road traffic information in the recommended route from the current position to the destination. Determining whether or not there is a congested link, bypassing the congested link and searching for a detour from the current position to the destination;
Determining whether to adopt the detour using the stored recommended route, the searched detour, and the link information;
When it is determined to be adopted, route guidance is performed using the detour, and when it is not determined to be adopted, a route guidance is performed using the stored recommended route, and
The step of determining includes
A branch point where the recommended route and the detour route branch is extracted, a link of a recommended route that enters the extracted branch point and a link connected to the branch point is specified, and the road type of the specified link A route guidance method for determining whether or not to adopt the detour according to a condition defined for each.

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